diff --git a/.gitignore b/.gitignore
index 74683483cc..05b99b77fc 100644
--- a/.gitignore
+++ b/.gitignore
@@ -34,9 +34,9 @@
 /projects/**/run/
 /projects/**/*.launch
 /repo/
-src/generated/resources/.cache/
-src/generated_test/resources/.cache/
-src/generated_mdk/resources/.cache/
+src/generated/resources/**/.cache/
+src/generated_test/resources/**/.cache/
+src/generated_mdk/resources/**/.cache/
 
 #Patch rejects
 #/patches-/
diff --git a/build.gradle b/build.gradle
index 39b9888242..83ce5272d5 100644
--- a/build.gradle
+++ b/build.gradle
@@ -68,6 +68,7 @@ ext {
     SLF4J_API_VERSION = '1.8.0-beta4'
     APACHE_MAVEN_ARTIFACT_VERSION = '3.8.5'
     JARJAR_VERSION = '0.3.19'
+	JIMFS_VERSION = '1.3.0' // Google's InMemory File System. Used by ForgeDev Tests for now, but could be useful for a lot of things.
 
     // These versions should be kept in sync with the version manifest JSON
     // To use a version newer than the version manifest JSON, the dependency must be added to the installer configuration
@@ -276,14 +277,17 @@ project(':clean') {
 }
 
 def sharedDeps = {
-    moduleonly "cpw.mods:securejarhandler:${SECUREJARHANDLER_VERSION}"
-    moduleonly "org.ow2.asm:asm:${ASM_VERSION}"
-    moduleonly "org.ow2.asm:asm-commons:${ASM_VERSION}"
-    moduleonly "org.ow2.asm:asm-tree:${ASM_VERSION}"
-    moduleonly "org.ow2.asm:asm-util:${ASM_VERSION}"
-    moduleonly "org.ow2.asm:asm-analysis:${ASM_VERSION}"
-    moduleonly "cpw.mods:bootstraplauncher:${BOOTSTRAPLAUNCHER_VERSION}"
-    moduleonly "net.minecraftforge:JarJarFileSystems:${JARJAR_VERSION}"
+    moduleonly("cpw.mods:securejarhandler:${SECUREJARHANDLER_VERSION}")
+    moduleonly("org.ow2.asm:asm:${ASM_VERSION}")
+    moduleonly("org.ow2.asm:asm-commons:${ASM_VERSION}")
+    moduleonly("org.ow2.asm:asm-tree:${ASM_VERSION}")
+    moduleonly("org.ow2.asm:asm-util:${ASM_VERSION}")
+    moduleonly("org.ow2.asm:asm-analysis:${ASM_VERSION}")
+    moduleonly("cpw.mods:bootstraplauncher:${BOOTSTRAPLAUNCHER_VERSION}")
+    moduleonly("net.minecraftforge:JarJarFileSystems:${JARJAR_VERSION}")
+    moduleonly("com.google.jimfs:jimfs:${JIMFS_VERSION}") {
+		transitive = false
+	}
 
     installer "cpw.mods:securejarhandler:${SECUREJARHANDLER_VERSION}"
     installer "org.ow2.asm:asm:${ASM_VERSION}"
@@ -320,50 +324,6 @@ def sharedDeps = {
 }
 
 def sharedFmlonlyForge = { Project prj ->
-    ['Client', 'Server', 'Joined'].each { side ->
-        ['slim', 'extra'].each { type ->
-            prj.task([type: DownloadMavenArtifact], "download${side}${type.capitalize()}") {
-                artifact = "net.minecraft:${side.toLowerCase()}:${MC_VERSION}-${MCP_VERSION}:${type}"
-            }
-        }
-
-        if (side.equals('Joined')) {
-            prj.task([type: DownloadMavenArtifact], "createJoinedSRG") {
-                artifact = "net.minecraft:joined:${MC_VERSION}-${MCP_VERSION}:srg"
-            }
-        } else {
-            prj.task([type: RenameJar, dependsOn: prj.tasks.createMcp2Srg], "create${side}SRG") {
-                tool = FART
-                args = [
-                        '--input', '{input}',
-                        '--output', '{output}',
-                        '--names', '{mappings}',
-                        '--ann-fix', '--ids-fix', '--src-fix', '--record-fix'
-                ]
-                mappings = prj.tasks.createMcp2Srg.srg
-                input = prj.tasks.getByName("download${side}Slim").output
-                output = prj.file("build/create${side}SRG/output.jar")
-            }
-        }
-
-        def gen = prj.tasks.getByName("gen${side}BinPatches")
-        def createSRG = prj.tasks.getByName("create${side}SRG")
-        gen.dependsOn(createSRG)
-        gen.tool = BINPATCH_TOOL
-        gen.cleanJar = createSRG.output
-
-        prj.task([type: ApplyBinPatches, dependsOn: gen], "apply${side}BinPatches") {
-            clean = gen.cleanJar
-            patch = gen.output
-            tool = BINPATCH_TOOL
-        }
-    }
-
-    prj.task([type: DownloadMavenArtifact], 'downloadInstaller') {
-        artifact = "net.minecraftforge:installer:${INSTALLER_VERSION}:shrunk"
-        changing = true
-    }
-
     prj.afterEvaluate {
         [prj.tasks.universalJar, prj.tasks.installerJar].each { t ->
             def signTask = prj.task([type: SignJar, dependsOn: t], "sign${t.name.capitalize()}") {
@@ -383,7 +343,6 @@ def sharedFmlonlyForge = { Project prj ->
     }
 
     prj.tasks.userdevConfig {
-        def launchPrefix = prj.name == "forge" ? "forge" : "fml"
         getArtifacts(prj, prj.configurations.installer, true).each { key, lib -> libraries.add(lib.name) }
         getArtifacts(prj, prj.configurations.moduleonly, true).each { key, lib ->
             libraries.add(lib.name)
@@ -396,46 +355,28 @@ def sharedFmlonlyForge = { Project prj ->
         inject = '' // We don't have a userdev sourceset anymore. Empty as a gradle workaround...
         runs {
             client {
-                environment 'MOD_CLASSES', '{source_roots}'
                 environment 'MCP_MAPPINGS', '{mcp_mappings}'
-
-                // Natives are loaded from the classpath now in all cases
-                // property 'nativesDirectory', '{natives}'
-                if (prj.name == 'forge') {
-                    property 'forge.enableGameTest', 'true'
-                }
-
-                args '--launchTarget', "${launchPrefix}clientuserdev"
+				property 'forge.enableGameTest', 'true'
+                args '--launchTarget', "forge_userdev_client"
                 args '--version', 'MOD_DEV'
                 args '--assetIndex', '{asset_index}'
                 args '--assetsDir', '{assets_root}'
             }
 
             server {
-                environment 'MOD_CLASSES', '{source_roots}'
                 environment 'MCP_MAPPINGS', '{mcp_mappings}'
-
-                if (prj.name == 'forge') {
-                    property 'forge.enableGameTest', 'true'
-                }
-
-                args '--launchTarget', "${launchPrefix}serveruserdev"
+				property 'forge.enableGameTest', 'true'
+                args '--launchTarget', "forge_userdev_server"
             }
 
-            if (prj.name == 'forge') {
-                gameTestServer {
-                    environment 'MOD_CLASSES', '{source_roots}'
-                    environment 'MCP_MAPPINGS', '{mcp_mappings}'
-
-                    args '--launchTarget', "${launchPrefix}gametestserveruserdev"
-                }
-            }
+			gameTestServer {
+				environment 'MCP_MAPPINGS', '{mcp_mappings}'
+				args '--launchTarget', "forge_userdev_server_gametest"
+			}
 
             data {
-                environment 'MOD_CLASSES', '{source_roots}'
                 environment 'MCP_MAPPINGS', '{mcp_mappings}'
-
-                args '--launchTarget', "${launchPrefix}datauserdev"
+                args '--launchTarget', "forge_userdev_data"
                 args '--assetIndex', '{asset_index}'
                 args '--assetsDir', '{assets_root}'
             }
@@ -456,11 +397,7 @@ def sharedFmlonlyForge = { Project prj ->
 
         run.jvmArgs '-Djava.net.preferIPv6Addresses=system'
 
-        if (run.name.contains('client')) {
-            run.client true
-        } else {
-            run.client false
-        }
+		run.client run.name.contains('client')
 
         // SecureJarHandler bootstrap values.
         run.property 'ignoreList', prj.configurations.moduleonly.files.collect {it.name.replaceAll(/([-_]([.\d]*\d+)|\.jar$)/, '') }.join(',') + ",client-extra,fmlcore,javafmllanguage,lowcodelanguage,mclanguage,${prj.name}-"
@@ -481,42 +418,29 @@ def sharedFmlonlyForge = { Project prj ->
         run.jvmArgs '--add-exports', 'jdk.naming.dns/com.sun.jndi.dns=java.naming'
     }
     for (def run : prj.patcher.runs) {
-        if (run.parents) continue // We already added this to the parent run config
+		def isTest = run.name.endsWith('_test')
+		
+		run.taskName = run.name
+		run.environment 'FORGE_SPEC', prj.SPEC_VERSION
+		run.workingDirectory prj.file('run/' + run.name)
+	    run.ideaModule rootProject.name + '.' + prj.name + '.' + (isTest ? 'test' : 'main')
+		
+		run.mods {
+			minecraft { source prj.sourceSets.main }
+		}
+		
+		if (isTest) {
+			run.property 'forge.enableGameTest', 'true'
 
-        if (run.name.contains('client') || run.name.contains('data')) {
-            // Natives are loaded from the classpath now in all cases
-            // run.property 'nativesDirectory', prj.extractNatives.output.get().asFile
-            run.args '--assetsDir', prj.downloadAssets.output
-            run.args '--assetIndex', "{asset_index}"
-        }
-
-        if (run.name.contains('client')) {
-            run.property 'org.lwjgl.system.SharedLibraryExtractDirectory', 'lwjgl_dll'
-            run.args '--username', 'Dev'
-            run.args '--version', prj.name
-            //run.args '--uuid', '0'
-            run.args '--accessToken', '0'
-            run.args '--userType', 'mojang'
-            run.args '--versionType', 'release'
-        }
-
-        if (prj.name == 'forge') {
-            run.environment 'FORGE_SPEC', prj.SPEC_VERSION
-        }
-    }
-
-    eclipse.project.resourceFilter {
-        appliesTo = 'FOLDERS'
-        type = 'EXCLUDE_ALL'
-        matcher {
-            id = 'org.eclipse.ui.ide.multiFilter'
-            arguments = '1.0-name-matches-false-false-run'
-        }
+			run.mods {
+				tests { sources prj.sourceSets.test }
+			}
+		}
     }
 
     def MODULE_PATH = Util.getArtifacts(prj, prj.configurations.moduleonly, false).values().collect{"libraries/${it.downloads.artifact.path}"}
     def tokens = [
-            TASK:          prj.name.equals('forge') ? 'forgeserver' : 'fmlserver',
+            TASK:          'forge_server',
             MAVEN_PATH:    prj.ext.MAVEN_PATH.toString(),
             FORGE_VERSION: FORGE_VERSION,
             MC_VERSION:    MC_VERSION,
@@ -560,8 +484,6 @@ def sharedFmlonlyForge = { Project prj ->
                 exclude 'args.txt'
                 filter(ReplaceTokens, tokens: tokens)
                 into('data/')
-                //rename 'run.sh',  "run_forge_${VERSION.replace('-', '_').sh"
-                //rename 'run.bat', "run_forge_${VERSION.replace('-', '_').bat"
             }
         }
     }
@@ -609,10 +531,21 @@ project(':forge') {
         }
     }
     
-    eclipse.classpath.file.whenMerged {
-        // Disable optional warnings on the minecraft decompiled source code. It just muddies the warning window and hides warnings in our own codebase
-        def src = entries.find { it.path == 'src/main/java' }
-        src.entryAttributes['ignore_optional_problems'] = 'true'
+    eclipse {
+		classpath.file.whenMerged {
+			// Disable optional warnings on the minecraft decompiled source code. It just muddies the warning window and hides warnings in our own codebase
+			def src = entries.find { it.path == 'src/main/java' }
+			src.entryAttributes['ignore_optional_problems'] = 'true'
+		}
+		
+		project.resourceFilter {
+			appliesTo = 'FOLDERS'
+			type = 'EXCLUDE_ALL'
+			matcher {
+				id = 'org.eclipse.ui.ide.multiFilter'
+				arguments = '1.0-name-matches-false-false-run'
+			}
+		}
     }
 
     ext {
@@ -661,160 +594,64 @@ project(':forge') {
 
         runs {
             forge_client {
-                workingDirectory file('run/client')
                 property 'eventbus.checkTypesOnDispatch', 'true'
-                args '--launchTarget', 'forgeclientdev'
-                ideaModule "${rootProject.name}.${project.name}.main"
-                mods {
-                    minecraft { source sourceSets.main }
-                }
+				property 'org.lwjgl.system.SharedLibraryExtractDirectory', 'lwjgl_dll'
+				
+                args '--launchTarget', 'forge_dev_client',
+					 '--username', 'Dev',
+					 '--version', project.name,
+					 '--accessToken', '0',
+					 '--userType', 'mojang',
+					 '--versionType', 'release',
+					 '--assetsDir', downloadAssets.output,
+					 '--assetIndex', "{asset_index}"
             }
 
-            forge_test_client {
-                workingDirectory file('run/client_test')
+            forge_client_test {
                 parent runs.forge_client
-                taskName 'forge_test_client'
-
-                property 'forge.enableGameTest', 'true'
-                environment 'MOD_CLASSES', 'dummy' // Needed to work around FG limitation, FG will replace this!
-
-                ideaModule "${rootProject.name}.${project.name}.test"
-
-                mods {
-                    tests { sources sourceSets.test }
-                }
             }
 
             forge_server {
-                workingDirectory file('run/server')
-                args '--launchTarget', 'forgeserverdev'
-                ideaModule "${rootProject.name}.${project.name}.main"
-
-                mods {
-                    minecraft { source sourceSets.main }
-                }
+                args '--launchTarget', 'forge_dev_server'
             }
 
-            forge_test_server {
-                workingDirectory file('run/server_test')
+            forge_server_test {
                 parent runs.forge_server
-                taskName 'forge_test_server'
-
-                property 'forge.enableGameTest', 'true'
-                environment 'MOD_CLASSES', 'dummy' // Needed to work around FG limitation, FG will replace this!
-
-                ideaModule "${rootProject.name}.${project.name}.test"
-
-                mods {
-                    tests { sources sourceSets.test }
-                }
             }
 
-            forge_gameTestServer {
-                taskName 'forge_gameTestServer'
-                args '--launchTarget', 'forgegametestserverdev'
-                ideaModule "${rootProject.name}.${project.name}.main"
-
-                mods {
-                    minecraft { source sourceSets.main }
-                }
+            forge_server_gametest {
+                args '--launchTarget', 'forge_dev_server_gametest'
             }
 
-            forge_test_gameTestServer {
-                parent runs.forge_gameTestServer
-                taskName 'forge_test_gameTestServer'
-
-                ideaModule "${rootProject.name}.${project.name}.test"
-
-                mods {
-                    tests { sources sourceSets.test }
-                }
+            forge_server_gametest_test {
+                parent runs.forge_server_gametest
             }
 
-            def forgeDataArgs = [
-                    '--mod', 'forge',
-                    '--all',
-                    '--output', rootProject.file('src/generated/resources/'),
-                    '--validate',
-                    '--existing', sourceSets.main.resources.srcDirs[0]
-                    ]
             forge_data {
-                taskName 'forge_data'
-                args '--launchTarget', 'forgedatadev'
-                ideaModule "${rootProject.name}.${project.name}.main"
-
-                mods {
-                    minecraft { source sourceSets.main }
-                }
-
-                args forgeDataArgs
+                args '--launchTarget', 'forge_dev_data',
+					 '--mod', 'forge',
+					 '--all',
+					 '--validate',
+					 '--output', rootProject.file('src/generated/resources/'),
+					 '--validate',
+					 '--existing', sourceSets.main.resources.srcDirs[0],
+					 '--assetsDir', downloadAssets.output,
+					 '--assetIndex', "{asset_index}"
             }
 
-            forge_test_data {
-                parent runs.forge_data
-                taskName 'forge_test_data'
-
-                environment 'MOD_CLASSES', 'dummy' // Needed to work around FG limitation, FG will replace this!
-
-                ideaModule "${rootProject.name}.${project.name}.test"
-
-                mods {
-                    tests { sources sourceSets.test }
-                }
-
-                afterEvaluate {
-                    // Clear forge's main datagen args
-                    args.removeAll {
-                        forgeDataArgs.contains(it instanceof File ? (it as File).absolutePath : it.toString())
-                    }
-
-                    args '--flat', '--all', '--validate',
-                            '--mod', 'empty',
-                            //'--mod', 'data_gen_test',
-                            //'--mod', 'piston_event_test',
-                            '--mod', 'global_loot_test',
-                            //'--mod', 'scaffolding_test',
-                            //'--mod', 'custom_tag_types_test',
-                            //'--mod', 'new_model_loader_test',
-                            //'--mod', 'remove_tag_datagen_test',
-                            //'--mod', 'tag_based_tool_types',
-                            //'--mod', 'custom_transformtype_test',
-                            //'--mod', 'data_pack_registries_test',
-                            //'--mod', 'biome_modifiers_test',
-                            //'--mod', 'structure_modifiers_test',
-                            //'--mod', 'custom_preset_editor_test',
-                            '--output', rootProject.file('src/generated_test/resources/'),
-                            '--existing', sourceSets.main.resources.srcDirs[0],
-                            '--existing', sourceSets.test.resources.srcDirs[0]
-                }
+            forge_data_test {
+				args '--launchTarget', 'forge_dev_data',
+					 '--mod', '.+',
+					 '--all', 
+					 '--validate',
+					 '--output', rootProject.file('src/generated_test/resources/'),
+					 '--existing', sourceSets.main.resources.srcDirs[0],
+					 '--existing', sourceSets.test.resources.srcDirs[0],
+					 '--assetsDir', downloadAssets.output,
+					 '--assetIndex', "{asset_index}"
             }
 
-            forge_mdk_data {
-                parent runs.forge_data
-                taskName 'forge_mdk_data'
-
-                environment 'MOD_CLASSES', 'dummy' // Needed to work around FG limitation, FG will replace this!
-
-                ideaModule "${rootProject.name}.${project.name}.test"
-
-                mods {
-                    tests { sources sourceSets.test }
-                }
-
-                afterEvaluate {
-                    // Clear forge's main datagen args
-                    args.removeAll {
-                        forgeDataArgs.contains(it instanceof File ? (it as File).absolutePath : it.toString())
-                    }
-
-                    args '--flat', '--all', '--validate',
-                            '--mod', 'mdk_datagen',
-                            '--output', rootProject.file('src/generated_mdk/resources/'),
-                            '--existing', sourceSets.main.resources.srcDirs[0],
-                            '--existing', sourceSets.test.resources.srcDirs[0]
-                }
-            }
-        }
+		}
     }
     
     afterEvaluate {
@@ -847,7 +684,6 @@ project(':forge') {
     ext {
         MANIFESTS = [
             '/': [
-                'Timestamp': new Date().format("yyyy-MM-dd'T'HH:mm:ssZ"),
                 'GitCommit': gradleutils.gitInfo.abbreviatedId,
                 'Git-Branch': gradleutils.gitInfo.branch,
                 'FML-System-Mods': 'forge'
@@ -914,7 +750,7 @@ project(':forge') {
         libraries.addAll downloadLibraries.librariesOutput.map { rf -> Files.readAllLines(rf.asFile.toPath()).stream().map(File::new).collect(java.util.stream.Collectors.toList()) }
     }
 
-    task findFieldInstanceChecks(type: FieldCompareFinder, dependsOn: ['createJoinedSRG']) {
+    tasks.register("findFieldInstanceChecks", FieldCompareFinder) {
         jar = createJoinedSRG.output
         output = rootProject.file('src/main/resources/coremods/field_to_instanceof.json')
         fields {
@@ -933,7 +769,7 @@ project(':forge') {
         }
     }
 
-    task findFinalizeSpawnTargets(type: BytecodePredicateFinder, dependsOn: ['createJoinedSRG']) {
+    tasks.register("findFinalizeSpawnTargets", BytecodePredicateFinder) {
         jar = createJoinedSRG.output
         output = rootProject.file('src/main/resources/coremods/finalize_spawn_targets.json')
         predicate = {
@@ -952,6 +788,74 @@ project(':forge') {
 
     tasks.jar.finalizedBy 'validateDeprecations'
 
+    tasks.register("downloadInstaller", DownloadMavenArtifact) {
+        artifact = "net.minecraftforge:installer:${INSTALLER_VERSION}:shrunk"
+        changing = true
+    }
+	tasks.register("downloadClientSlim", DownloadMavenArtifact) {
+		artifact = "net.minecraft:client:${MC_VERSION}-${MCP_VERSION}:slim"
+	}
+	tasks.register("downloadClientExtra", DownloadMavenArtifact) {
+		artifact = "net.minecraft:client:${MC_VERSION}-${MCP_VERSION}:extra"
+	}
+	tasks.register("downloadServerSlim", DownloadMavenArtifact) {
+		artifact = "net.minecraft:server:${MC_VERSION}-${MCP_VERSION}:slim"
+	}
+	tasks.register("downloadServerExtra", DownloadMavenArtifact) {
+		artifact = "net.minecraft:server:${MC_VERSION}-${MCP_VERSION}:extra"
+	}
+	tasks.register("downloadJoinedSlim", DownloadMavenArtifact) {
+		artifact = "net.minecraft:joined:${MC_VERSION}-${MCP_VERSION}:slim"
+	}
+	tasks.register("downloadJoinedExtra", DownloadMavenArtifact) {
+		artifact = "net.minecraft:joined:${MC_VERSION}-${MCP_VERSION}:extra"
+	}
+	tasks.register("createJoinedSRG", DownloadMavenArtifact) {
+		artifact = "net.minecraft:joined:${MC_VERSION}-${MCP_VERSION}:srg"
+	}
+	tasks.register("createClientSRG", RenameJar) {
+		tool = FART
+		args = ['--input', '{input}', '--output', '{output}', '--names', '{mappings}', '--ann-fix', '--ids-fix', '--src-fix', '--record-fix']
+		mappings = createMcp2Srg.srg
+		input = downloadClientSlim.output
+		output = file("build/createClientSRG/output.jar")
+	}
+	tasks.register("createServerSRG", RenameJar) {
+		tool = FART
+		args = ['--input', '{input}', '--output', '{output}', '--names', '{mappings}', '--ann-fix', '--ids-fix', '--src-fix', '--record-fix']
+		mappings = createMcp2Srg.srg
+		input = downloadServerSlim.output
+		output = file("build/createServerSRG/output.jar")
+	}	
+	genClientBinPatches {
+		tool = BINPATCH_TOOL
+		cleanJar = createClientSRG.output
+	}
+	genServerBinPatches {
+		tool = BINPATCH_TOOL
+		cleanJar = createServerSRG.output
+	}
+	genJoinedBinPatches {
+		tool = BINPATCH_TOOL
+		cleanJar = createJoinedSRG.output
+	}
+	tasks.register("applyClientBinPatches", ApplyBinPatches) {
+		tool = BINPATCH_TOOL
+		clean = genClientBinPatches.cleanJar
+		patch = genClientBinPatches.output
+	}
+	tasks.register("applyServerBinPatches", ApplyBinPatches) {
+		tool = BINPATCH_TOOL
+		clean = genServerBinPatches.cleanJar
+		patch = genServerBinPatches.output
+	}
+	tasks.register("applyJoinedBinPatches", ApplyBinPatches) {
+		tool = BINPATCH_TOOL
+		clean = genJoinedBinPatches.cleanJar
+		patch = genJoinedBinPatches.output
+	}
+
+	
     tasks.register('checkAll') {
         dependsOn 'checkLicenses'
         group = 'checks'
@@ -1065,7 +969,7 @@ project(':forge') {
                 inheritsFrom: MC_VERSION,
                 logging: {},
                 arguments: [
-                    game: ['--launchTarget', 'forgeclient',
+                    game: ['--launchTarget', 'forge_client',
                            '--fml.forgeVersion', FORGE_VERSION,
                            '--fml.mcVersion', MC_VERSION,
                            '--fml.forgeGroup', project.group,
@@ -1369,7 +1273,7 @@ project(':forge') {
             rename 'gitignore\\.txt', '.gitignore'
             rename 'gitattributes\\.txt', '.gitattributes'
         }
-        from(rootProject.file('src/generated_mdk/resources/')) {
+        from(rootProject.file('src/generated_test/resources/mdk_datagen/')) {
             into('src/main/resources/')
             exclude '**/.cache/'
         }
diff --git a/fmlloader/build.gradle b/fmlloader/build.gradle
index 7d29c81b72..ffacc03c0a 100644
--- a/fmlloader/build.gradle
+++ b/fmlloader/build.gradle
@@ -35,6 +35,7 @@ dependencies {
     implementation("cpw.mods:securejarhandler:${SECUREJARHANDLER_VERSION}")
     implementation("net.minecraftforge:accesstransformers:${ACCESSTRANSFORMERS_VERSION}")
     implementation("net.minecrell:terminalconsoleappender:${TERMINALCONSOLEAPPENDER_VERSION}")
+    implementation("com.google.jimfs:jimfs:${JIMFS_VERSION}")
     // implementation("org.jline:jline:${JLINE_VERSION}")
 
     implementation("org.apache.logging.log4j:log4j-core:${LOG4J_VERSION}")
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/common/asm/ObjectHolderDefinalize.java b/fmlloader/src/main/java/net/minecraftforge/fml/common/asm/ObjectHolderDefinalize.java
index 1337ec2f46..517adc0631 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/common/asm/ObjectHolderDefinalize.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/common/asm/ObjectHolderDefinalize.java
@@ -56,6 +56,7 @@ public class ObjectHolderDefinalize implements ILaunchPluginService {
         return lst != null && lst.stream().anyMatch(n -> n.desc.equals(OBJECT_HOLDER));
     }
 
+    @SuppressWarnings("unused")
     private String getValue(List<AnnotationNode> lst)
     {
         AnnotationNode ann = lst.stream().filter(n -> n.desc.equals(OBJECT_HOLDER)).findFirst().get();
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/common/asm/RuntimeEnumExtender.java b/fmlloader/src/main/java/net/minecraftforge/fml/common/asm/RuntimeEnumExtender.java
index f92012eca7..32bc948558 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/common/asm/RuntimeEnumExtender.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/common/asm/RuntimeEnumExtender.java
@@ -20,8 +20,6 @@ import org.objectweb.asm.tree.MethodNode;
 
 import cpw.mods.modlauncher.serviceapi.ILaunchPluginService;
 import org.slf4j.Logger;
-import org.slf4j.Marker;
-import org.slf4j.MarkerFactory;
 
 /**
  * Modifies specified enums to allow runtime extension by making the $VALUES field non-final and
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/BackgroundWaiter.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/BackgroundWaiter.java
index cac3c4f5c2..3be9974cd6 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/BackgroundWaiter.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/BackgroundWaiter.java
@@ -5,8 +5,6 @@
 
 package net.minecraftforge.fml.loading;
 
-import net.minecraftforge.fml.loading.progress.StartupNotificationManager;
-
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/EarlyLoadingException.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/EarlyLoadingException.java
index 371fe9e44b..ec2cfe5c72 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/EarlyLoadingException.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/EarlyLoadingException.java
@@ -14,6 +14,8 @@ import java.util.List;
  * or server.
  */
 public class EarlyLoadingException extends RuntimeException {
+    private static final long serialVersionUID = 2302192216172508006L;
+
     public static class ExceptionData {
         private final IModInfo modInfo;
         private final String i18message;
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLConfig.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLConfig.java
index 88ed60233e..2c8b7a8735 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLConfig.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLConfig.java
@@ -42,7 +42,6 @@ public class FMLConfig
         private final String entry;
         private final Object defaultValue;
         private final String comment;
-        private final Class<?> valueType;
         private final Function<Object, Object> entryFunction;
 
         ConfigValue(final String entry, final Object defaultValue, final String comment) {
@@ -52,7 +51,6 @@ public class FMLConfig
             this.entry = entry;
             this.defaultValue = defaultValue;
             this.comment = comment;
-            this.valueType = defaultValue.getClass();
             this.entryFunction = entryFunction;
         }
 
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLLoader.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLLoader.java
index 721b9a18f8..d5f7c79430 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLLoader.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLLoader.java
@@ -16,7 +16,6 @@ import net.minecraftforge.fml.loading.moddiscovery.ModFile;
 import net.minecraftforge.fml.loading.moddiscovery.ModValidator;
 import net.minecraftforge.accesstransformer.service.AccessTransformerService;
 import net.minecraftforge.api.distmarker.Dist;
-import net.minecraftforge.fml.loading.progress.StartupNotificationManager;
 import net.minecraftforge.fml.loading.targets.CommonLaunchHandler;
 import net.minecraftforge.forgespi.Environment;
 import net.minecraftforge.forgespi.coremod.ICoreModProvider;
@@ -137,6 +136,7 @@ public class FMLLoader
             throw new RuntimeException("Missing launch handler: " + launchTarget);
         }
 
+        // TODO: What the fuck is the point of using a service if you require a specific concrete class
         if (!(launchHandler.get() instanceof CommonLaunchHandler)) {
             LOGGER.error(CORE, "Incompatible Launch handler found - type {}, cannot continue", launchHandler.get().getClass().getName());
             throw new RuntimeException("Incompatible launch handler found");
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLServiceProvider.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLServiceProvider.java
index e8647f17f5..d297620d8e 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLServiceProvider.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/FMLServiceProvider.java
@@ -126,6 +126,7 @@ public class FMLServiceProvider implements ITransformationService
         targetMcpMappings = option.value(mappingsOption);
     }
 
+    @SuppressWarnings("rawtypes")
     @Override
     public @NotNull List<ITransformer> transformers()
     {
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/FileUtils.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/FileUtils.java
deleted file mode 100644
index 570d8d3789..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/FileUtils.java
+++ /dev/null
@@ -1,35 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading;
-
-import java.io.File;
-import java.nio.file.Path;
-
-public class FileUtils
-{
-
-    public static String fileExtension(final Path path) {
-        String fileName = path.getFileName().toString();
-        int idx = fileName.lastIndexOf('.');
-        if (idx > -1) {
-            return fileName.substring(idx+1);
-        } else {
-            return "";
-        }
-    }
-
-    public static boolean matchFileName(String path, String... matches) {
-        // Extract file name from path
-        String name = path.substring(Math.min(path.lastIndexOf(File.separatorChar) + 1, path.length()));
-        // Check if it contains any of the desired keywords
-        for (String match : matches) {
-            if (name.contains(match)) {
-                return true;
-            }
-        }
-        return false;
-    }
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/JarVersionLookupHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/JarVersionLookupHandler.java
index 491b240cce..b3f0c8e5eb 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/JarVersionLookupHandler.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/JarVersionLookupHandler.java
@@ -11,6 +11,7 @@ import java.util.Optional;
  * Finds Version data from a package, with possible default values
  */
 public class JarVersionLookupHandler {
+
     public static Optional<String> getImplementationVersion(final String pkgName) {
         // Note that with Java 9, you'll probably want the module's version data, hence pulling this out
         final String pkgVersion = Package.getPackage(pkgName).getImplementationVersion();
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/LanguageLoadingProvider.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/LanguageLoadingProvider.java
index e1663a1ea0..edaf98a2bd 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/LanguageLoadingProvider.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/LanguageLoadingProvider.java
@@ -9,7 +9,6 @@ import com.mojang.logging.LogUtils;
 import cpw.mods.modlauncher.Launcher;
 import cpw.mods.modlauncher.api.IModuleLayerManager;
 import cpw.mods.modlauncher.util.ServiceLoaderUtils;
-import net.minecraftforge.fml.loading.progress.StartupNotificationManager;
 import net.minecraftforge.forgespi.language.IModLanguageProvider;
 import net.minecraftforge.fml.loading.moddiscovery.ExplodedDirectoryLocator;
 import net.minecraftforge.fml.loading.moddiscovery.ModFile;
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModDirTransformerDiscoverer.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModDirTransformerDiscoverer.java
index 9609f85638..072ab5d44c 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModDirTransformerDiscoverer.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModDirTransformerDiscoverer.java
@@ -7,7 +7,6 @@ package net.minecraftforge.fml.loading;
 
 import com.mojang.logging.LogUtils;
 import cpw.mods.jarhandling.SecureJar;
-import cpw.mods.modlauncher.Launcher;
 import cpw.mods.modlauncher.api.LamdbaExceptionUtils;
 import cpw.mods.modlauncher.api.NamedPath;
 import cpw.mods.modlauncher.serviceapi.ITransformerDiscoveryService;
@@ -19,8 +18,6 @@ import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.List;
-import java.util.ServiceLoader;
-import java.util.zip.ZipFile;
 import java.util.Set;
 
 public class ModDirTransformerDiscoverer implements ITransformerDiscoveryService {
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModJarURLHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModJarURLHandler.java
deleted file mode 100644
index 19b8220b7e..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModJarURLHandler.java
+++ /dev/null
@@ -1,96 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading;
-
-import com.mojang.logging.LogUtils;
-import cpw.mods.modlauncher.api.LamdbaExceptionUtils;
-import org.slf4j.Logger;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.net.URL;
-import java.net.URLConnection;
-import java.net.URLStreamHandler;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.Objects;
-import java.util.Optional;
-import java.util.jar.Manifest;
-
-import static net.minecraftforge.fml.loading.LogMarkers.CORE;
-
-public class ModJarURLHandler extends URLStreamHandler
-{
-    private static final Logger LOGGER = LogUtils.getLogger();
-    // modjar://modid/path/to/file
-    @Override
-    protected URLConnection openConnection(URL url) {
-        return new ModJarURLConnection(url);
-    }
-
-    @Override
-    protected int hashCode(final URL u) {
-        return Objects.hash(u.getHost(), u.getFile());
-    }
-
-    @Override
-    protected boolean equals(final URL u1, final URL u2) {
-        return Objects.equals(u1.getProtocol(), u2.getProtocol())
-                && Objects.equals(u1.getHost(), u2.getHost())
-                && Objects.equals(u1.getFile(), u2.getFile());
-    }
-
-    static class ModJarURLConnection extends URLConnection {
-        private Path resource;
-        private String modpath;
-        private String modid;
-        private Optional<Manifest> manifest;
-
-        public ModJarURLConnection(final URL url) {
-            super(url);
-        }
-
-        @Override
-        public void connect()
-        {
-//            if (resource == null) {
-//                modid = url.getHost();
-//                // trim first char
-//                modpath = url.getPath().substring(1);
-//                resource = FMLLoader.getLoadingModList().getModFileById(modid).getFile().findResource(modpath);
-//                manifest = FMLLoader.getLoadingModList().getModFileById(modid).getManifest();
-//            }
-        }
-
-        @Override
-        public InputStream getInputStream() throws IOException
-        {
-            connect();
-            LOGGER.trace(CORE, "Loading modjar URL {} got resource {} {}", url, resource, resource != null ? Files.exists(resource) : "missing");
-            return Files.newInputStream(resource);
-        }
-
-        @Override
-        public long getContentLengthLong() {
-            try {
-                connect();
-                return Files.size(resource);
-            } catch (IOException e) {
-                return -1L;
-            }
-        }
-
-        // Used to cache protectiondomains by "top level object" aka the modid
-        @Override
-        public URL getURL() {
-            return LamdbaExceptionUtils.uncheck(()->new URL("modjar://"+modid));
-        }
-
-        public Optional<Manifest> getManifest() {
-            return manifest;
-        }
-    }
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModSorter.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModSorter.java
index ea9e1b35b7..bd40d36555 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModSorter.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/ModSorter.java
@@ -10,7 +10,6 @@ import com.google.common.graph.MutableGraph;
 import com.mojang.logging.LogUtils;
 import cpw.mods.jarhandling.SecureJar;
 import net.minecraftforge.fml.loading.moddiscovery.MinecraftLocator;
-import net.minecraftforge.forgespi.language.IModFileInfo;
 import net.minecraftforge.forgespi.language.IModInfo;
 import net.minecraftforge.fml.loading.EarlyLoadingException.ExceptionData;
 import net.minecraftforge.fml.loading.moddiscovery.ModFile;
@@ -72,7 +71,6 @@ public class ModSorter
         }
     }
 
-    @SuppressWarnings("UnstableApiUsage")
     private void sort()
     {
         // lambdas are identity based, so sorting them is impossible unless you hold reference to them
@@ -121,7 +119,6 @@ public class ModSorter
                 .collect(toList());
     }
 
-    @SuppressWarnings("UnstableApiUsage")
     private void addDependency(MutableGraph<ModFileInfo> topoGraph, IModInfo.ModVersion dep)
     {
         final ModFileInfo self = (ModFileInfo)dep.getOwner().getOwningFile();
@@ -133,6 +130,7 @@ public class ModSorter
         switch (dep.getOrdering()) {
             case BEFORE -> topoGraph.putEdge(self, target);
             case AFTER -> topoGraph.putEdge(target, self);
+            default -> {}
         }
     }
 
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/AbstractModProvider.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/AbstractModProvider.java
index 12fecc540b..c3c855b1e2 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/AbstractModProvider.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/AbstractModProvider.java
@@ -27,8 +27,7 @@ import java.util.Optional;
 import java.util.function.Function;
 import java.util.jar.Manifest;
 
-public abstract class AbstractModProvider implements IModProvider
-{
+public abstract class AbstractModProvider implements IModProvider {
     private static final   Logger LOGGER    = LogUtils.getLogger();
     protected static final String MODS_TOML = "META-INF/mods.toml";
     protected static final String MANIFEST = "META-INF/MANIFEST.MF";
@@ -36,25 +35,24 @@ public abstract class AbstractModProvider implements IModProvider
     protected IModLocator.ModFileOrException createMod(Path... path) {
         var mjm = new ModJarMetadata();
         var sj = SecureJar.from(
-                Manifest::new,
-                jar -> jar.moduleDataProvider().findFile(MODS_TOML).isPresent() ? mjm : JarMetadata.from(jar, path),
-                path
+            Manifest::new,
+            jar -> jar.moduleDataProvider().findFile(MODS_TOML).isPresent() ? mjm : JarMetadata.from(jar, path),
+            path
         );
 
         IModFile mod;
         var type = sj.moduleDataProvider().getManifest().getMainAttributes().getValue(ModFile.TYPE);
-        if (type == null) {
+        if (type == null)
             type = getDefaultJarModType();
-        }
+
         if (sj.moduleDataProvider().findFile(MODS_TOML).isPresent()) {
             LOGGER.debug(LogMarkers.SCAN, "Found {} mod of type {}: {}", MODS_TOML, type, path);
             mod = new ModFile(sj, this, ModFileParser::modsTomlParser);
         } else if (type != null) {
             LOGGER.debug(LogMarkers.SCAN, "Found {} mod of type {}: {}", MANIFEST, type, path);
             mod = new ModFile(sj, this, this::manifestParser, type);
-        } else {
-            return new IModLocator.ModFileOrException(null, new ModFileLoadingException("Invalid mod file found "+ Arrays.toString(path)));
-        }
+        } else
+            return new IModLocator.ModFileOrException(null, new ModFileLoadingException("Invalid mod file found " + Arrays.toString(path)));
 
         mjm.setModFile(mod);
         return new IModLocator.ModFileOrException(mod, null);
@@ -87,36 +85,19 @@ public abstract class AbstractModProvider implements IModProvider
     }
 
     private record DefaultModFileInfo(IModFile mod, String license, IConfigurable configurable) implements IModFileInfo, IConfigurable {
-        @Override
-        public <T> Optional<T> getConfigElement(final String... strings)
-        {
-            return Optional.empty();
-        }
-
-        @Override
-        public List<? extends IConfigurable> getConfigList(final String... strings)
-        {
-            return null;
-        }
-
+        @Override public <T> Optional<T> getConfigElement(final String... strings) { return Optional.empty(); }
+        @Override public List<? extends IConfigurable> getConfigList(final String... strings) { return null; }
         @Override public List<IModInfo> getMods() { return Collections.emptyList(); }
         @Override public List<LanguageSpec> requiredLanguageLoaders() { return Collections.emptyList(); }
         @Override public boolean showAsResourcePack() { return false; }
         @Override public Map<String, Object> getFileProperties() { return Collections.emptyMap(); }
-        @Override
-        public String getLicense() { return license; }
-
+        @Override public String getLicense() { return license; }
         @Override public IModFile getFile() { return mod; }
         @Override public IConfigurable getConfig() { return configurable; }
-
         // These Should never be called as it's only called from ModJarMetadata.version and we bypass that
         @Override public String moduleName() { return mod.getSecureJar().name(); }
         @Override public String versionString() { return null; }
         @Override public List<String> usesServices() { return null; }
-
-        @Override
-        public String toString() {
-            return "IModFileInfo(" + mod.getFilePath() + ")";
-        }
+        @Override public String toString() { return "IModFileInfo(" + mod.getFilePath() + ")"; }
     }
 }
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ClasspathLocator.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ClasspathLocator.java
index 0a8f482ced..347d8d639d 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ClasspathLocator.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ClasspathLocator.java
@@ -12,12 +12,9 @@ import org.slf4j.Logger;
 
 import java.io.File;
 import java.io.IOException;
-import java.net.URI;
-import java.net.URISyntaxException;
 import java.net.URL;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Enumeration;
@@ -25,8 +22,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.stream.Stream;
 
-public class ClasspathLocator extends AbstractJarFileModLocator
-{
+public class ClasspathLocator extends AbstractJarFileModLocator {
     private static final Logger LOGGER = LogUtils.getLogger();
     private final List<Path> legacyClasspath = Arrays.stream(System.getProperty("legacyClassPath", "").split(File.pathSeparator)).map(Path::of).toList();
     private boolean enabled = false;
@@ -73,22 +69,4 @@ public class ClasspathLocator extends AbstractJarFileModLocator
         var launchTarget = (String) arguments.get("launchTarget");
         enabled = launchTarget != null && launchTarget.contains("dev");
     }
-
-    private Path findJarPathFor(final String resourceName, final String jarName, final URL resource) {
-        try {
-            Path path;
-            final URI uri = resource.toURI();
-            if (uri.getScheme().equals("jar") && uri.getRawSchemeSpecificPart().contains("!/")) {
-                int lastExcl = uri.getRawSchemeSpecificPart().lastIndexOf("!/");
-                path = Paths.get(new URI(uri.getRawSchemeSpecificPart().substring(0, lastExcl)));
-            } else {
-                path = Paths.get(new URI("file://"+uri.getRawSchemeSpecificPart().substring(0, uri.getRawSchemeSpecificPart().length()-resourceName.length())));
-            }
-            //LOGGER.debug(CORE, "Found JAR {} at path {}", jarName, path.toString());
-            return path;
-        } catch (NullPointerException | URISyntaxException e) {
-            LOGGER.error(LogMarkers.SCAN, "Failed to find JAR for class {} - {}", resourceName, jarName);
-            throw new RuntimeException("Unable to locate "+resourceName+" - "+jarName, e);
-        }
-    }
 }
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/InvalidModFileException.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/InvalidModFileException.java
index 1177e18972..8e57e3729e 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/InvalidModFileException.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/InvalidModFileException.java
@@ -11,12 +11,11 @@ import net.minecraftforge.forgespi.locating.ModFileLoadingException;
 import java.util.Locale;
 import java.util.Optional;
 
-public class InvalidModFileException extends ModFileLoadingException
-{
+public class InvalidModFileException extends ModFileLoadingException {
+    private static final long serialVersionUID = 1230464325917450374L;
     private final IModFileInfo modFileInfo;
 
-    public InvalidModFileException(String message, IModFileInfo modFileInfo)
-    {
+    public InvalidModFileException(String message, IModFileInfo modFileInfo) {
         super(String.format(Locale.ROOT, "%s (%s)", message, Optional.ofNullable(modFileInfo).map(mf->mf.getFile().getFileName()).orElse("MISSING FILE NAME")));
         this.modFileInfo = modFileInfo;
     }
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModAnnotationVisitor.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModAnnotationVisitor.java
index d48dd65df3..8fd1fd3e34 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModAnnotationVisitor.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModAnnotationVisitor.java
@@ -10,72 +10,58 @@ import org.objectweb.asm.Opcodes;
 
 import java.util.LinkedList;
 
-public class ModAnnotationVisitor extends AnnotationVisitor
-{
+public class ModAnnotationVisitor extends AnnotationVisitor {
     private final ModAnnotation annotation;
     private LinkedList<ModAnnotation> annotations;
     private boolean array;
-    private String name;
     private boolean isSubAnnotation;
 
-    public ModAnnotationVisitor(LinkedList<ModAnnotation> annotations, ModAnnotation annotation)
-    {
+    public ModAnnotationVisitor(LinkedList<ModAnnotation> annotations, ModAnnotation annotation) {
         super(Opcodes.ASM9);
         this.annotations = annotations;
         this.annotation = annotation;
     }
 
-    public ModAnnotationVisitor(LinkedList<ModAnnotation> annotations, ModAnnotation annotation, String name)
-    {
+    public ModAnnotationVisitor(LinkedList<ModAnnotation> annotations, ModAnnotation annotation, String name) {
         this(annotations, annotation);
         this.array = true;
-        this.name = name;
         annotation.addArray(name);
     }
 
-    public ModAnnotationVisitor(LinkedList<ModAnnotation> annotations, ModAnnotation annotation, boolean isSubAnnotation)
-    {
+    public ModAnnotationVisitor(LinkedList<ModAnnotation> annotations, ModAnnotation annotation, boolean isSubAnnotation) {
         this(annotations, annotation);
         this.isSubAnnotation = true;
     }
 
     @Override
-    public void visit(String key, Object value)
-    {
+    public void visit(String key, Object value) {
         annotation.addProperty(key, value);
     }
 
     @Override
-    public void visitEnum(String name, String desc, String value)
-    {
+    public void visitEnum(String name, String desc, String value) {
         annotation.addEnumProperty(name, desc, value);
     }
 
     @Override
-    public AnnotationVisitor visitArray(String name)
-    {
+    public AnnotationVisitor visitArray(String name) {
         return new ModAnnotationVisitor(annotations, annotation, name);
     }
+
     @Override
-    public AnnotationVisitor visitAnnotation(String name, String desc)
-    {
-        ModAnnotation ma = annotations.getFirst();
-        final ModAnnotation childAnnotation = ma.addChildAnnotation(name, desc);
+    public AnnotationVisitor visitAnnotation(String name, String desc) {
+        var ma = annotations.getFirst();
+        var childAnnotation = ma.addChildAnnotation(name, desc);
         annotations.addFirst(childAnnotation);
-        return new ModAnnotationVisitor(annotations, childAnnotation,true);
+        return new ModAnnotationVisitor(annotations, childAnnotation, true);
     }
+
     @Override
-    public void visitEnd()
-    {
+    public void visitEnd() {
         if (array)
-        {
             annotation.endArray();
-        }
 
         if (isSubAnnotation)
-        {
-            ModAnnotation child = annotations.removeFirst();
-            annotations.addLast(child);
-        }
+            annotations.addLast(annotations.removeFirst());
     }
 }
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModFile.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModFile.java
index f95c4dedb1..164add39ab 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModFile.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModFile.java
@@ -10,7 +10,6 @@ import com.mojang.logging.LogUtils;
 import cpw.mods.jarhandling.SecureJar;
 import net.minecraftforge.fml.loading.FMLLoader;
 import net.minecraftforge.fml.loading.LogMarkers;
-import net.minecraftforge.fml.loading.progress.StartupNotificationManager;
 import net.minecraftforge.forgespi.language.IModFileInfo;
 import net.minecraftforge.forgespi.language.IModInfo;
 import net.minecraftforge.forgespi.language.IModLanguageProvider;
@@ -207,8 +206,11 @@ public class ModFile implements IModFile {
         this.securityStatus = status;
     }
 
-    public ArtifactVersion getJarVersion()
-    {
+    public SecureJar.Status getSecurityStatus() {
+        return this.securityStatus;
+    }
+
+    public ArtifactVersion getJarVersion() {
         return new DefaultArtifactVersion(this.jarVersion);
     }
 
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModFileParser.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModFileParser.java
index 9d519b5aaa..9cac458341 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModFileParser.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModFileParser.java
@@ -22,7 +22,6 @@ import java.nio.file.Path;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
-import java.util.stream.Collectors;
 
 public class ModFileParser {
     private static final Logger LOGGER = LogUtils.getLogger();
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModListHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModListHandler.java
index a9b4a9233d..471d1fb6aa 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModListHandler.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModListHandler.java
@@ -7,7 +7,6 @@ package net.minecraftforge.fml.loading.moddiscovery;
 
 import com.mojang.logging.LogUtils;
 import net.minecraftforge.fml.loading.FMLPaths;
-import net.minecraftforge.fml.loading.FileUtils;
 import net.minecraftforge.fml.loading.LogMarkers;
 import net.minecraftforge.fml.loading.MavenCoordinateResolver;
 import org.apache.commons.lang3.tuple.Pair;
@@ -63,7 +62,7 @@ public class ModListHandler {
             return Collections.emptyList();
         }
 
-        String extension = FileUtils.fileExtension(filePath);
+        String extension = fileExtension(filePath);
         if (Objects.equals("list",extension)) {
             return readListFile(filePath).stream().filter(s -> !s.isEmpty()).collect(Collectors.toList());
         } else {
@@ -72,6 +71,12 @@ public class ModListHandler {
         return Collections.emptyList();
     }
 
+    private static String fileExtension(final Path path) {
+        String fileName = path.getFileName().toString();
+        int idx = fileName.lastIndexOf('.');
+        return idx > -1 ? fileName.substring(idx+1) : "";
+    }
+
     /**
      * Simple list file, ending in ".list" with one mod coordinate per line
      * @param filePath path
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModValidator.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModValidator.java
index 08e3275b58..2483ac4397 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModValidator.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/moddiscovery/ModValidator.java
@@ -9,7 +9,6 @@ import com.mojang.logging.LogUtils;
 import cpw.mods.modlauncher.api.IModuleLayerManager;
 import cpw.mods.modlauncher.api.ITransformationService;
 import net.minecraftforge.fml.loading.*;
-import net.minecraftforge.fml.loading.progress.StartupNotificationManager;
 import net.minecraftforge.forgespi.language.IModFileInfo;
 import net.minecraftforge.forgespi.locating.IModFile;
 import org.jetbrains.annotations.NotNull;
@@ -23,7 +22,7 @@ import java.util.stream.Collectors;
 
 public class ModValidator {
     private static final Logger LOGGER = LogUtils.getLogger();
-    private final Map<IModFile.Type, List<ModFile>> modFiles;
+    //private final Map<IModFile.Type, List<ModFile>> modFiles;
     private final List<ModFile> candidatePlugins;
     private final List<ModFile> candidateMods;
     private LoadingModList loadingModList;
@@ -31,7 +30,7 @@ public class ModValidator {
     private final List<EarlyLoadingException.ExceptionData> discoveryErrorData;
 
     public ModValidator(final Map<IModFile.Type, List<ModFile>> modFiles, final List<IModFileInfo> brokenFiles, final List<EarlyLoadingException.ExceptionData> discoveryErrorData) {
-        this.modFiles = modFiles;
+        //this.modFiles = modFiles;
         this.candidateMods = lst(modFiles.get(IModFile.Type.MOD));
         this.candidateMods.addAll(lst(modFiles.get(IModFile.Type.GAMELIBRARY)));
         this.candidatePlugins = lst(modFiles.get(IModFile.Type.LANGPROVIDER));
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/progress/StartupNotificationManager.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/progress/StartupNotificationManager.java
index 56b26f739d..2e714d5ed1 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/progress/StartupNotificationManager.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/progress/StartupNotificationManager.java
@@ -10,8 +10,6 @@ import com.google.common.base.CharMatcher;
 
 import java.util.*;
 import java.util.function.Consumer;
-import java.util.stream.Stream;
-import java.util.stream.StreamSupport;
 
 public class StartupNotificationManager {
     private static volatile EnumMap<Message.MessageType, List<Message>> messages = new EnumMap<>(Message.MessageType.class);
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ArgumentList.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ArgumentList.java
index 69ce04db9e..cf17ddf779 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ArgumentList.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ArgumentList.java
@@ -6,6 +6,8 @@
 package net.minecraftforge.fml.loading.targets;
 
 import com.mojang.logging.LogUtils;
+
+import org.jetbrains.annotations.ApiStatus;
 import org.slf4j.Logger;
 
 import java.util.ArrayList;
@@ -19,6 +21,7 @@ import java.util.function.Supplier;
  * A class that attempts to parse command line arguments into key value pairs to allow addition and editing.
  * Can not use JOptSimple as that doesn't parse out the values for keys unless the spec says it has a value.
  */
+@ApiStatus.Internal
 class ArgumentList {
     private static final Logger LOGGER = LogUtils.getLogger();
     private List<Supplier<String[]>> entries = new ArrayList<>();
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonClientLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonClientLaunchHandler.java
deleted file mode 100644
index 6225f4df06..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonClientLaunchHandler.java
+++ /dev/null
@@ -1,47 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import cpw.mods.modlauncher.api.ServiceRunner;
-import net.minecraftforge.fml.loading.FMLLoader;
-import net.minecraftforge.fml.loading.LibraryFinder;
-import net.minecraftforge.fml.loading.VersionInfo;
-import net.minecraftforge.api.distmarker.Dist;
-
-import java.nio.file.Path;
-import java.util.List;
-import java.util.stream.Stream;
-
-public abstract class CommonClientLaunchHandler extends CommonLaunchHandler {
-    @Override public Dist getDist()  { return Dist.CLIENT; }
-    @Override public String getNaming() { return "srg"; }
-    @Override public boolean isProduction() { return true; }
-
-    @Override
-    protected ServiceRunner makeService(final String[] arguments, final ModuleLayer gameLayer) {
-        return ()->clientService(arguments, gameLayer);
-    }
-
-    @Override
-    public LocatedPaths getMinecraftPaths() {
-        final var vers = FMLLoader.versionInfo();
-        var mc = LibraryFinder.findPathForMaven("net.minecraft", "client", "", "srg", vers.mcAndMCPVersion());
-        var mcextra = LibraryFinder.findPathForMaven("net.minecraft", "client", "", "extra", vers.mcAndMCPVersion());
-        var mcstream = Stream.<Path>builder().add(mc).add(mcextra);
-        var modstream = Stream.<List<Path>>builder();
-
-        processMCStream(vers, mcstream, modstream);
-
-        var fmlcore = LibraryFinder.findPathForMaven(vers.forgeGroup(), "fmlcore", "", "", vers.mcAndForgeVersion());
-        var javafmllang = LibraryFinder.findPathForMaven(vers.forgeGroup(), "javafmllanguage", "", "", vers.mcAndForgeVersion());
-        var lowcodelang = LibraryFinder.findPathForMaven(vers.forgeGroup(), "lowcodelanguage", "", "", vers.mcAndForgeVersion());
-        var mclang = LibraryFinder.findPathForMaven(vers.forgeGroup(), "mclanguage", "", "", vers.mcAndForgeVersion());
-
-        return new LocatedPaths(mcstream.build().toList(), null, modstream.build().toList(), List.of(fmlcore, javafmllang, lowcodelang, mclang));
-    }
-
-    protected abstract void processMCStream(VersionInfo versionInfo, Stream.Builder<Path> mc, Stream.Builder<List<Path>> mods);
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonDevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonDevLaunchHandler.java
index 5a8ba6d897..19e586ed3b 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonDevLaunchHandler.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonDevLaunchHandler.java
@@ -7,46 +7,30 @@ package net.minecraftforge.fml.loading.targets;
 
 import cpw.mods.jarhandling.SecureJar;
 import cpw.mods.modlauncher.api.ServiceRunner;
-import net.minecraftforge.fml.loading.FileUtils;
-
+import net.minecraftforge.fml.loading.LogMarkers;
 import java.io.File;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
-import java.util.Objects;
+import java.util.Map;
+import java.util.Optional;
 import java.util.function.BiPredicate;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
-import java.util.stream.Stream;
 
-public abstract class CommonDevLaunchHandler extends CommonLaunchHandler {
+import org.jetbrains.annotations.ApiStatus;
+
+@ApiStatus.Internal
+abstract class CommonDevLaunchHandler extends CommonLaunchHandler {
+    protected CommonDevLaunchHandler(LaunchType type, String prefix) {
+        super(type, prefix);
+    }
+
     @Override public String getNaming() { return "mcp"; }
     @Override public boolean isProduction() { return false; }
 
-    @Override
-    public LocatedPaths getMinecraftPaths() {
-        // Minecraft is extra jar {resources} + our exploded directories in dev
-        final var mcstream = Stream.<Path>builder();
-
-        // The extra jar is on the classpath, so try and pull it out of the legacy classpath
-        var legacyCP = Objects.requireNonNull(System.getProperty("legacyClassPath"), "Missing legacyClassPath, cannot find client-extra").split(File.pathSeparator);
-        var extra = findJarOnClasspath(legacyCP, "client-extra");
-
-        // The MC code/Patcher edits are in exploded directories
-        final var modstream = Stream.<List<Path>>builder();
-        final var mods = getModClasses();
-        final var minecraft = mods.remove("minecraft");
-        if (minecraft == null)
-            throw new IllegalStateException("Could not find 'minecraft' mod paths.");
-        minecraft.stream().distinct().forEach(mcstream::add);
-        mods.values().forEach(modstream::add);
-
-        mcstream.add(extra);
-        var mcFilter = getMcFilter(extra, minecraft, modstream);
-        return new LocatedPaths(mcstream.build().toList(), mcFilter, modstream.build().toList(), getFmlStuff(legacyCP));
-    }
-
     @Override
     protected String[] preLaunch(String[] arguments, ModuleLayer layer) {
         super.preLaunch(arguments, layer);
@@ -79,34 +63,34 @@ public abstract class CommonDevLaunchHandler extends CommonLaunchHandler {
         return args.getArguments();
     }
 
-    protected List<Path> getFmlStuff(String[] classpath) {
-        // We also want the FML things, fmlcore, javafmllanguage, mclanguage, I don't like hard coding these, but hey whatever works for now.
-        return Arrays.stream(classpath)
-            .filter(e -> FileUtils.matchFileName(e, "fmlcore", "javafmllanguage", "lowcodelanguage", "mclanguage"))
-            .map(Paths::get)
-            .toList();
+    protected List<Path> getLibraries(String[] classpath) {
+        // TODO: These should all be FMLModType: LIBRARY, find them that way?
+        // Or at the very least include version info
+        var fmlcore = findJarOnClasspath(classpath, "fmlcore");
+        var javafmllang = findJarOnClasspath(classpath, "javafmllanguage");
+        var lowcodelang = findJarOnClasspath(classpath, "lowcodelanguage");
+        var mclang = findJarOnClasspath(classpath, "mclanguage");
+        return List.of(fmlcore, javafmllang, lowcodelang, mclang);
     }
 
-    protected static Path findJarOnClasspath(String[] classpath, String match) {
-        return Paths.get(Arrays.stream(classpath)
-            .filter(e -> FileUtils.matchFileName(e, match))
-            .findFirst()
-            .orElseThrow(() -> new IllegalStateException("Could not find " + match + " in classpath")));
-    }
-
-    protected BiPredicate<String, String> getMcFilter(Path extra, List<Path> minecraft, Stream.Builder<List<Path>> mods) {
-        final var packages = getPackages();
-        final var extraPath = extra.toString().replace('\\', '/');
+    protected BiPredicate<String, String> getMcFilter(Path extra, List<Path> minecraft) {
+        var packages = getPackages(); // Pulled out so it is passed to the lambda as value
+        var extraPath = extra.toString().replace('\\', '/');
 
         // We serve everything, except for things in the forge packages.
         BiPredicate<String, String> mcFilter = (path, base) -> {
             if (base.equals(extraPath) ||
-                    path.endsWith("/")) return true;
+                path.endsWith("/")) return true;
             for (var pkg : packages)
                 if (path.startsWith(pkg)) return false;
             return true;
         };
 
+        return mcFilter;
+    }
+
+    protected Path getForgeMod(List<Path> minecraft) {
+        var packages = getPackages(); // Pulled out so it is passed to the lambda as value
         // We need to separate out our resources/code so that we can show up as a different data pack.
         var modJar = SecureJar.from((path, base) -> {
             if (!path.endsWith(".class")) return true;
@@ -114,14 +98,18 @@ public abstract class CommonDevLaunchHandler extends CommonLaunchHandler {
                 if (path.startsWith(pkg)) return true;
             return false;
         }, minecraft.stream().distinct().toArray(Path[]::new));
-        //modJar.getPackages().stream().sorted().forEach(System.out::println);
-        mods.add(List.of(modJar.getRootPath()));
 
-        return mcFilter;
+        //modJar.getPackages().stream().sorted().forEach(System.out::println);
+        return modJar.getRootPath();
     }
 
-    protected String[] getPackages() {
-        return new String[]{ "net/minecraftforge/", "META-INF/services/", "META-INF/coremods.json", "META-INF/mods.toml" };
+    private static String[] getPackages() {
+        return new String[] {
+            "net/minecraftforge/",
+            "META-INF/services/",
+            "META-INF/coremods.json",
+            "META-INF/mods.toml"
+        };
     }
 
     private static String getRandomNumbers(int length) {
@@ -131,9 +119,70 @@ public abstract class CommonDevLaunchHandler extends CommonLaunchHandler {
 
     @Override
     protected ServiceRunner makeService(final String[] arguments, final ModuleLayer gameLayer) {
-        var args = preLaunch(arguments, gameLayer);
-        return ()->devService(args, gameLayer);
+        return super.makeService(preLaunch(arguments, gameLayer), gameLayer);
     }
 
-    abstract void devService(final String[] arguments, final ModuleLayer gameLayer) throws Throwable;
+    // TODO: Get rid of this string based classpath crap when I re-write mod loader
+    protected static Map<String, List<Path>> getModClasses() {
+        var modClasses = Optional.ofNullable(System.getenv("MOD_CLASSES")).orElse("");
+        LOGGER.debug(LogMarkers.CORE, "Got mod coordinates {} from env", modClasses);
+
+        /*
+         * So MOD_CLASSES at the end of the day is a Map<ModId, List<Path>> but because we want to shove that into a single string.
+         * And pass it in as an environment variable.. instead od using json, or a file path, or anything sane, cpw did hacky string stuff
+         * Basically what we want to do is split the string by File.pathSeperator to get each key-value pair.
+         * Then we find the magic string "%%" and split on that. Using the first half as the mod id and the second as the path.
+         * BUT the modID is optional, and if not specified {why wouldn't it be?} it uses "defaultmodid"
+         * Anyways, it was stream hell, but now it's simpler to debug/understand.
+         */
+        Map<String, List<Path>> ret = new HashMap<>();
+        var entries = modClasses.split(File.pathSeparator);
+        for (var entry : entries) {
+            var modid = "defaultmodid";
+            var path = entry;
+
+            int idx = entry.indexOf("%%");
+            if (idx != -1) {
+                modid = entry.substring(0, idx);
+                path = entry.substring(idx + 2);
+            }
+
+            var p = Paths.get(path);
+            var lst = ret.computeIfAbsent(modid, k -> new ArrayList<>());
+            if (!lst.contains(p))
+                lst.add(p);
+        }
+
+        LOGGER.debug(LogMarkers.CORE, "Found supplied mod coordinates:");
+        ret.forEach((k, v) -> {
+            if (v.size() == 1)
+                LOGGER.debug(LogMarkers.CORE, "\t{}: {}", k, v.get(0));
+            else {
+                LOGGER.debug(LogMarkers.CORE, "\t{}:", k);
+                v.forEach(e -> LOGGER.debug("\t\t{}", e));
+            }
+        });
+
+        return ret;
+    }
+
+    protected static Path findJarOnClasspath(String[] classpath, String match) {
+        String ret = null;
+
+        for (var entry : classpath) {
+            int idx = entry.lastIndexOf(File.separatorChar);
+            if (idx == -1) continue;
+
+            var name = entry.substring(idx + 1);
+            if (name.startsWith(match)) {
+                ret = entry;
+                break;
+            }
+        }
+
+        if (ret == null)
+            new IllegalStateException("Could not find " + match + " in classpath");
+
+        return Paths.get(ret);
+    }
 }
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonLaunchHandler.java
index 2a9aaf95d3..13d7aa12c7 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonLaunchHandler.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonLaunchHandler.java
@@ -10,49 +10,52 @@ import cpw.mods.modlauncher.api.ILaunchHandlerService;
 import cpw.mods.modlauncher.api.ITransformingClassLoaderBuilder;
 import cpw.mods.modlauncher.api.ServiceRunner;
 import net.minecraftforge.fml.loading.FMLLoader;
-import net.minecraftforge.fml.loading.LogMarkers;
 import net.minecraftforge.api.distmarker.Dist;
 import org.apache.logging.log4j.core.LoggerContext;
 import org.apache.logging.log4j.core.config.ConfigurationFactory;
 import org.apache.logging.log4j.core.config.ConfigurationSource;
 import org.apache.logging.log4j.core.config.Configurator;
 import org.slf4j.Logger;
-import sun.misc.Unsafe;
-
-import java.io.File;
 import java.io.IOException;
 import java.net.URI;
 import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.util.Arrays;
 import java.util.List;
-import java.util.Map;
-import java.util.Optional;
 import java.util.function.BiPredicate;
-import java.util.stream.Collectors;
 
+/**
+ * This is required by FMLLoader because ILaunchHandlerService doesn't have the context we need.
+ * I need to clean this up to make proper api. But that involves editing ModLauncher itself which i'm not gunna do right now.
+ *
+ * So until that happens, guess this is public api.
+ */
 public abstract class CommonLaunchHandler implements ILaunchHandlerService {
-    public record LocatedPaths(List<Path> minecraftPaths, BiPredicate<String, String> minecraftFilter, List<List<Path>> otherModPaths, List<Path> otherArtifacts) {}
+    public record LocatedPaths(
+        List<Path> minecraftPaths,
+        BiPredicate<String, String> minecraftFilter,
+        List<List<Path>> otherModPaths,
+        List<Path> otherArtifacts
+    ) {}
 
     protected static final Logger LOGGER = LogUtils.getLogger();
 
-    public abstract Dist getDist();
+    private final LaunchType type;
+    private final String prefix;
 
+    protected CommonLaunchHandler(LaunchType type, String prefix) {
+        this.type = type;
+        this.prefix = prefix;
+    }
+
+    @Override public String name() { return this.prefix + this.type.name(); }
+    public Dist getDist() { return this.type.dist(); }
+    public boolean isData() { return this.type.data(); }
+    public boolean isProduction() { return false; }
     public abstract String getNaming();
 
-    public boolean isProduction() {
-        return false;
-    }
-
-    public boolean isData() {
-        return false;
-    }
-
     public abstract LocatedPaths getMinecraftPaths();
 
     @Override
     public void configureTransformationClassLoader(final ITransformingClassLoaderBuilder builder) {
-
     }
 
     protected String[] preLaunch(String[] arguments, ModuleLayer layer) {
@@ -69,45 +72,23 @@ public abstract class CommonLaunchHandler implements ILaunchHandlerService {
         return arguments;
     }
 
-    protected final Map<String, List<Path>> getModClasses() {
-        final String modClasses = Optional.ofNullable(System.getenv("MOD_CLASSES")).orElse("");
-        LOGGER.debug(LogMarkers.CORE, "Got mod coordinates {} from env", modClasses);
-
-        record ExplodedModPath(String modid, Path path) {}
-        // "a/b/;c/d/;" -> "modid%%c:\fish\pepper;modid%%c:\fish2\pepper2\;modid2%%c:\fishy\bums;modid2%%c:\hmm"
-        final var modClassPaths = Arrays.stream(modClasses.split(File.pathSeparator))
-                .map(inp -> inp.split("%%", 2))
-                .map(splitString -> new ExplodedModPath(splitString.length == 1 ? "defaultmodid" : splitString[0], Paths.get(splitString[splitString.length - 1])))
-                .collect(Collectors.groupingBy(ExplodedModPath::modid, Collectors.mapping(ExplodedModPath::path, Collectors.toList())));
-
-        LOGGER.debug(LogMarkers.CORE, "Found supplied mod coordinates [{}]", modClassPaths);
-
-        //final var explodedTargets = ((Map<String, List<ExplodedDirectoryLocator.ExplodedMod>>)arguments).computeIfAbsent("explodedTargets", a -> new ArrayList<>());
-        //modClassPaths.forEach((modlabel,paths) -> explodedTargets.add(new ExplodedDirectoryLocator.ExplodedMod(modlabel, paths)));
-        return modClassPaths;
-    }
-
     @Override
     public ServiceRunner launchService(final String[] arguments, final ModuleLayer gameLayer) {
         FMLLoader.beforeStart(gameLayer);
         return makeService(arguments, gameLayer);
     }
 
-    protected abstract ServiceRunner makeService(final String[] arguments, final ModuleLayer gameLayer);
-
-    protected void clientService(final String[] arguments, final ModuleLayer layer) throws Throwable {
-        runTarget("net.minecraft.client.main.Main", arguments, layer);
+    protected ServiceRunner makeService(final String[] arguments, final ModuleLayer gameLayer) {
+        return () -> runTarget(this.type.module(), this.type.main(), arguments, gameLayer);
     }
 
-    protected void serverService(final String[] arguments, final ModuleLayer layer) throws Throwable {
-        runTarget("net.minecraft.server.Main", arguments, layer);
-    }
+    protected record LaunchType(String name, String module, String main, Dist dist, boolean data) {};
+    protected static final LaunchType CLIENT          = new LaunchType("client", "minecraft", "net.minecraft.client.main.Main", Dist.CLIENT, false);
+    protected static final LaunchType DATA            = new LaunchType("data",   "minecraft", "net.minecraft.data.Main", Dist.CLIENT, true);
+    protected static final LaunchType SERVER          = new LaunchType("server", "minecraft", "net.minecraft.server.Main", Dist.DEDICATED_SERVER, false);
+    protected static final LaunchType SERVER_GAMETEST = new LaunchType("server_gametest", "forge", "net.minecratforge.gametest.GameTestMain", Dist.DEDICATED_SERVER, false);
 
-    protected void dataService(final String[] arguments, final ModuleLayer layer) throws Throwable {
-        runTarget("net.minecraft.data.Main", arguments, layer);
-    }
-
-    protected void runTarget(final String target, final String[] arguments, final ModuleLayer layer) throws Throwable {
-        Class.forName(layer.findModule("minecraft").orElseThrow(),target).getMethod("main", String[].class).invoke(null, (Object)arguments);
+    protected void runTarget(String module, String target, final String[] arguments, final ModuleLayer layer) throws Throwable {
+        Class.forName(layer.findModule(module).orElseThrow(),target).getMethod("main", String[].class).invoke(null, (Object)arguments);
     }
 }
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonServerLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonServerLaunchHandler.java
deleted file mode 100644
index a041f63c47..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonServerLaunchHandler.java
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import cpw.mods.jarhandling.SecureJar;
-import cpw.mods.modlauncher.api.ServiceRunner;
-import net.minecraftforge.fml.loading.FMLLoader;
-import net.minecraftforge.fml.loading.LibraryFinder;
-import net.minecraftforge.fml.loading.VersionInfo;
-import net.minecraftforge.api.distmarker.Dist;
-
-import java.nio.file.Path;
-import java.util.List;
-import java.util.function.BiPredicate;
-import java.util.stream.Stream;
-
-public abstract class CommonServerLaunchHandler extends CommonLaunchHandler {
-    @Override public Dist getDist()  { return Dist.DEDICATED_SERVER; }
-    @Override public String getNaming() { return "srg"; }
-    @Override public boolean isProduction() { return true; }
-
-    @Override
-    protected ServiceRunner makeService(String[] arguments, ModuleLayer layer) {
-        return () -> serverService(arguments, layer);
-    }
-
-    @Override
-    public LocatedPaths getMinecraftPaths() {
-        final var vers = FMLLoader.versionInfo();
-        var mc = LibraryFinder.findPathForMaven("net.minecraft", "server", "", "srg", vers.mcAndMCPVersion());
-        var mcextra = LibraryFinder.findPathForMaven("net.minecraft", "server", "", "extra", vers.mcAndMCPVersion());
-        var mcextra_filtered = SecureJar.from( // We only want it for it's resources. So filter everything else out.
-            (path, base) -> {
-                return path.equals("META-INF/versions/") || // This is required because it bypasses our filter for the manifest, and it's a multi-release jar.
-                     (!path.endsWith(".class") &&
-                      !path.startsWith("META-INF/"));
-            }, mcextra
-        );
-
-        var mcstream = Stream.<Path>builder().add(mc).add(mcextra_filtered.getRootPath());
-        var modstream = Stream.<List<Path>>builder();
-
-        BiPredicate<String, String> filter = processMCStream(vers, mcstream, null, modstream);
-
-        var fmlcore = LibraryFinder.findPathForMaven(vers.forgeGroup(), "fmlcore", "", "", vers.mcAndForgeVersion());
-        var javafmllang = LibraryFinder.findPathForMaven(vers.forgeGroup(), "javafmllanguage", "", "", vers.mcAndForgeVersion());
-        var lowcodelang = LibraryFinder.findPathForMaven(vers.forgeGroup(), "lowcodelanguage", "", "", vers.mcAndForgeVersion());
-        var mclang = LibraryFinder.findPathForMaven(vers.forgeGroup(), "mclanguage", "", "", vers.mcAndForgeVersion());
-
-        return new LocatedPaths(mcstream.build().toList(), filter, modstream.build().toList(), List.of(fmlcore, javafmllang, lowcodelang, mclang));
-    }
-
-    protected abstract BiPredicate<String, String> processMCStream(VersionInfo versionInfo, Stream.Builder<Path> mc, BiPredicate<String, String> filter, Stream.Builder<List<Path>> mods);
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonUserdevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonUserdevLaunchHandler.java
deleted file mode 100644
index cbc31398c2..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/CommonUserdevLaunchHandler.java
+++ /dev/null
@@ -1,42 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.fml.loading.FMLLoader;
-import net.minecraftforge.fml.loading.VersionInfo;
-
-import java.io.File;
-import java.nio.file.Path;
-import java.util.List;
-import java.util.Objects;
-import java.util.stream.Collectors;
-import java.util.stream.Stream;
-
-public abstract class CommonUserdevLaunchHandler extends CommonDevLaunchHandler {
-    @Override
-    public LocatedPaths getMinecraftPaths() {
-        final var vers = FMLLoader.versionInfo();
-
-        // Minecraft is extra jar {resources} + forge jar {patches}
-        final var mcstream = Stream.<Path>builder();
-        // Mod code is in exploded directories
-        final var modstream = Stream.<List<Path>>builder();
-
-        // The MC extra and forge jars are on the classpath, so try and pull them out
-        var legacyCP = Objects.requireNonNull(System.getProperty("legacyClassPath"), "Missing legacyClassPath, cannot find userdev jars").split(File.pathSeparator);
-        var extra = findJarOnClasspath(legacyCP, "client-extra");
-
-        processStreams(legacyCP, vers, mcstream, modstream);
-        getModClasses().forEach((modid, paths) -> modstream.add(paths));
-
-        var minecraft = mcstream.build().collect(Collectors.toList());
-        var mcFilter = getMcFilter(extra, minecraft, modstream);
-        minecraft.add(extra); // Add extra late so the filter is made correctly
-        return new LocatedPaths(minecraft, mcFilter, modstream.build().toList(), getFmlStuff(legacyCP));
-    }
-
-    protected abstract void processStreams(String[] classpath, VersionInfo versionInfo, Stream.Builder<Path> mc, Stream.Builder<List<Path>> mods);
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientDevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientDevLaunchHandler.java
deleted file mode 100644
index 7bae42b620..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientDevLaunchHandler.java
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.api.distmarker.Dist;
-
-public class ForgeClientDevLaunchHandler extends CommonDevLaunchHandler {
-    @Override public String name() { return "forgeclientdev"; }
-    @Override public Dist getDist() { return Dist.CLIENT; }
-
-    @Override
-    public void devService(String[] arguments, ModuleLayer layer) throws Throwable {
-        clientService(arguments, layer);
-    }
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientLaunchHandler.java
deleted file mode 100644
index bbc51f6a11..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientLaunchHandler.java
+++ /dev/null
@@ -1,25 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import java.nio.file.Path;
-import java.util.List;
-import java.util.stream.Stream;
-
-import net.minecraftforge.fml.loading.LibraryFinder;
-import net.minecraftforge.fml.loading.VersionInfo;
-
-public class ForgeClientLaunchHandler extends CommonClientLaunchHandler {
-    @Override public String name() { return "forgeclient"; }
-
-    @Override
-    protected void processMCStream(VersionInfo versionInfo, Stream.Builder<Path> mc, Stream.Builder<List<Path>> mods) {
-        var forgepatches = LibraryFinder.findPathForMaven(versionInfo.forgeGroup(), "forge", "", "client", versionInfo.mcAndForgeVersion());
-        var forgejar = LibraryFinder.findPathForMaven(versionInfo.forgeGroup(), "forge", "", "universal", versionInfo.mcAndForgeVersion());
-        mc.add(forgepatches);
-        mods.add(List.of(forgejar));
-    }
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientUserdevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientUserdevLaunchHandler.java
deleted file mode 100644
index 08b8d90cc4..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeClientUserdevLaunchHandler.java
+++ /dev/null
@@ -1,21 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.api.distmarker.Dist;
-
-public class ForgeClientUserdevLaunchHandler extends ForgeUserdevLaunchHandler {
-    @Override
-    public String name() { return "forgeclientuserdev"; }
-
-    @Override
-    public Dist getDist() { return Dist.CLIENT; }
-
-    @Override
-    public void devService(String[] arguments, ModuleLayer layer) throws Throwable {
-        clientService(arguments, layer);
-    }
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDataDevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDataDevLaunchHandler.java
deleted file mode 100644
index 307e09f5a0..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDataDevLaunchHandler.java
+++ /dev/null
@@ -1,19 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.api.distmarker.Dist;
-
-public class ForgeDataDevLaunchHandler extends CommonDevLaunchHandler {
-    @Override public String name() { return "forgedatadev"; }
-    @Override public Dist getDist() { return Dist.CLIENT; }
-    @Override public boolean isData() { return true; }
-
-    @Override
-    public void devService(String[] arguments, ModuleLayer layer) throws Throwable {
-        Class.forName(layer.findModule("minecraft").orElseThrow(), "net.minecraft.data.Main").getMethod("main", String[].class).invoke(null, (Object) arguments);
-    }
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDataUserdevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDataUserdevLaunchHandler.java
deleted file mode 100644
index a5995577f1..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDataUserdevLaunchHandler.java
+++ /dev/null
@@ -1,24 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.api.distmarker.Dist;
-
-public class ForgeDataUserdevLaunchHandler extends ForgeUserdevLaunchHandler {
-    @Override
-    public String name() { return "forgedatauserdev"; }
-
-    @Override
-    public Dist getDist() { return Dist.CLIENT; }
-
-    @Override
-    public boolean isData() { return true; }
-
-    @Override
-    public void devService(String[] arguments, ModuleLayer layer) throws Throwable {
-        dataService(arguments, layer);
-    }
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDevLaunchHandler.java
new file mode 100644
index 0000000000..690ace158b
--- /dev/null
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeDevLaunchHandler.java
@@ -0,0 +1,295 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.fml.loading.targets;
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+import java.nio.file.spi.FileSystemProvider;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.stream.Stream;
+
+import org.jetbrains.annotations.ApiStatus;
+import org.objectweb.asm.AnnotationVisitor;
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.Opcodes;
+import com.electronwill.nightconfig.core.Config;
+import com.electronwill.nightconfig.core.file.FileNotFoundAction;
+import com.electronwill.nightconfig.core.io.WritingMode;
+import com.electronwill.nightconfig.toml.TomlParser;
+import com.electronwill.nightconfig.toml.TomlWriter;
+import com.google.common.jimfs.Jimfs;
+
+import cpw.mods.niofs.union.UnionFileSystemProvider;
+
+@ApiStatus.Internal
+abstract class ForgeDevLaunchHandler extends CommonDevLaunchHandler {
+    private static final String MODS_TOML = "META-INF/mods.toml";
+    private static final String PACK_META = "pack.mcmeta";
+    private static final UnionFileSystemProvider UFSP = (UnionFileSystemProvider)FileSystemProvider.installedProviders().stream().filter(fsp->fsp.getScheme().equals("union")).findFirst().orElseThrow(()->new IllegalStateException("Couldn't find UnionFileSystemProvider"));
+
+    private ForgeDevLaunchHandler(LaunchType type) {
+        super(type, "forge_dev_");
+    }
+
+    @Override
+    public LocatedPaths getMinecraftPaths() {
+        // Our exploded directories in development include all mods and minecraft itself.
+        var mods = getModClasses();
+
+        // The extra jar is on the classpath, so try and pull it out of the legacy classpath
+        var legacyCP = Objects.requireNonNull(System.getProperty("legacyClassPath"), "Missing legacyClassPath, cannot find client-extra").split(File.pathSeparator);
+        var extra = findJarOnClasspath(legacyCP, "client-extra");
+
+
+        // Minecraft is extra jar {resources} + our exploded directories in dev
+        var minecraft = mods.remove("minecraft");
+        if (minecraft == null)
+            throw new IllegalStateException("Could not find 'minecraft' mod paths.");
+        var mcFilter = getMcFilter(extra, minecraft);
+
+        // The MC code/Patcher edits are in exploded directories
+        var modstream = Stream.<List<Path>>builder();
+        var forge = this.getForgeMod(minecraft);
+        modstream.add(List.of(forge));
+
+        // Explode our test mods into a framework that treats them all as separate jars.
+        var tests = mods.remove("tests");
+        if (tests != null)
+            explodeTestMods(tests).forEach(modstream::add);
+
+        mods.values().forEach(modstream::add);
+
+        return new LocatedPaths(
+            Stream.concat(minecraft.stream(), List.of(extra).stream()).toList(),
+            mcFilter,
+            modstream.build().toList(),
+            getLibraries(legacyCP)
+        );
+    }
+
+    private List<List<Path>> explodeTestMods(List<Path> paths) {
+        var mod = new ArrayList<List<Path>>();
+        var memory = Jimfs.newFileSystem();
+
+        // First lets find all class files, that have the @Mod annotation and map packages to modids.
+        var packages = findTestModPackages(paths);
+        for (var entry : packages.entrySet()) {
+            var pkg = entry.getKey();
+            var modids = entry.getValue();
+
+            var resourcePaths = new LinkedHashSet<Path>();
+            // Jump down into the package for resources
+            paths.stream()
+                .<Path>mapMulti((p, c) -> modids.forEach(id -> c.accept(p.resolve(id))))
+                .filter(Files::exists).forEach(resourcePaths::add);
+
+            var root = memory.getPath(modids.iterator().next()); // use the first modid as our root
+            buildModsToml(resourcePaths, modids, root);
+            buildPackMeta(resourcePaths, root);
+
+            if (Files.exists(root))
+                resourcePaths.add(root);
+
+            // We want just the class files from the root of the input paths. So make a new union with a filter.
+            var classes = UFSP.newFileSystem(
+                (path, base) -> {
+                    if (path.endsWith("/")) {
+                        if (path.startsWith("/"))
+                            path = path.substring(1);
+                        return pkg.startsWith(path) || path.startsWith(pkg);
+                    }
+                    return path.endsWith(".class") && path.startsWith(pkg);
+                }, paths.toArray(Path[]::new));
+            // And we want the resources, and none of the classes, just in case things get kinda fucky and somehow a package overlaps a sub package {shading?}
+            var resources = UFSP.newFileSystem((path, base) -> !path.endsWith(".class"), resourcePaths.toArray(Path[]::new));
+
+            mod.add(List.of(classes.getRoot(), resources.getRoot()));
+        }
+
+        return mod;
+    }
+
+    // Find all the @Mods so we can generate tomls, and so we can pick packages. Right now it doesn't allow mods in parent directories,
+    // I could make it merge all the way up, but I think this would be fine.
+    private Map<String, Set<String>> findTestModPackages(List<Path> paths) {
+        var mods = new HashMap<String, Set<String>>();
+        for (var path : paths) {
+            try (var files = Files.walk(path)) {
+                var classes = files
+                    .filter(Files::isRegularFile)
+                    .filter(p -> p.getFileName().toString().endsWith(".class"))
+                    .toList();
+
+                for (var cls : classes) {
+                    try (var is = Files.newInputStream(cls)) {
+                        var reader = new ClassReader(is);
+                        reader.accept(new ClassVisitor(Opcodes.ASM9) {
+                            private String clsName;
+                            @Override
+                            public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
+                                this.clsName = name;
+                                super.visit(version, access, name, signature, superName, interfaces);
+                            }
+
+                            @Override
+                            public AnnotationVisitor visitAnnotation(String name, boolean runtime) {
+                                if (!"Lnet/minecraftforge/fml/common/Mod;".equals(name))
+                                    return super.visitAnnotation(name, runtime);
+
+                                return new AnnotationVisitor(Opcodes.ASM9) {
+                                    @Override
+                                    public void visit(String key, Object value) {
+                                        if ("value".equals(key)) {
+                                            int idx = clsName.lastIndexOf('/');
+                                            var pkg = clsName.substring(0, idx);
+                                            mods.computeIfAbsent(pkg, k -> new HashSet<>()).add((String)value);
+
+                                            idx = pkg.lastIndexOf('/');
+                                            while (idx != -1) {
+                                                pkg = pkg.substring(0, idx);
+                                                idx = pkg.lastIndexOf('/');
+                                                if (mods.containsKey(pkg))
+                                                    throw new IllegalStateException("Invalid ForgeDev test mod layout, conflicting packages: " + pkg + " for " + clsName);
+                                            }
+                                        }
+                                    }
+                                };
+                            }
+                        }, ClassReader.SKIP_CODE | ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES);
+                    }
+                }
+            } catch (IOException e) {
+                sneak(e);
+            }
+        }
+        return mods;
+    }
+
+    // Builds or update the mods.toml file for all @Mods in this package
+    private void buildModsToml(Set<Path> resources, Set<String> modids, Path root) {
+        var toml = resources.stream()
+            .map(p -> p.resolve(MODS_TOML))
+            .filter(Files::exists)
+            .findFirst()
+            .orElse(null);
+
+        Config cfg = null;
+
+        if (toml != null)
+            cfg = new TomlParser().parse(toml, FileNotFoundAction.READ_NOTHING);
+        else
+            cfg = Config.inMemory();
+
+        boolean modified = false;
+        var defaults = Map.of(
+            "modLoader", "javafml",
+            "loaderVersion", "[0,)",
+            "license", "Doesnt fucking matter"
+        );
+
+        for (var key : defaults.keySet()) {
+            if (!cfg.contains(key)) {
+                cfg.set(key, defaults.get(key));
+                modified = true;
+            }
+        }
+
+        var modlist = new ArrayList<Config>();
+        if (cfg.contains("mods")) {
+            @SuppressWarnings("unchecked")
+            var existing = ((List<Config>)cfg.get("mods"));
+            modlist.addAll(existing);
+        }
+
+        for (var modid : modids) {
+            if (!modlist.stream().anyMatch(c -> modid.equals(c.get("modId")))) {
+                modified = true;
+                var tmp = Config.inMemory();
+                tmp.set("modId", modid);
+                modlist.add(tmp);
+            }
+        }
+
+        cfg.set("mods", modlist);
+
+        if (modified) {
+            var target = root.resolve(MODS_TOML);
+            try {
+                Files.createDirectories(target.getParent());
+                new TomlWriter().write(cfg, target, WritingMode.REPLACE);
+            } catch (IOException e) {
+                throw new IllegalStateException("Failed to create in memory toml: " + target, e);
+            }
+        }
+    }
+
+    // This is optional, it just hides a warning screen when starting up. I should probably remove this once I restructure how data gen for test mods work and make it generate there.
+    private void buildPackMeta(Set<Path> paths, Path root) {
+        var existing = paths.stream()
+                .map(p -> p.resolve(PACK_META))
+                .filter(Files::exists)
+                .findFirst()
+                .orElse(null);
+
+        if (existing != null)
+            return;
+        var target = root.resolve(PACK_META);
+        try {
+            Files.createDirectories(target.getParent());
+            Files.writeString(target,
+            """
+            {
+                "pack": {
+                    "description": "doesn't matter",
+                    "pack_format": 18
+                 }
+            }
+            """, StandardCharsets.UTF_8, StandardOpenOption.WRITE, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.CREATE);
+        } catch (IOException e) {
+            throw new IllegalStateException("Failed to make in memory pack.mcmeta: " + target, e);
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    private static <E extends Throwable, R> R sneak(Throwable e) throws E {
+        throw (E)e;
+    }
+
+    public static class Client extends ForgeDevLaunchHandler {
+        public Client() {
+            super(CLIENT);
+        }
+    }
+
+    public static class Data extends ForgeDevLaunchHandler {
+        public Data() {
+            super(DATA);
+        }
+    }
+
+    public static class Server extends ForgeDevLaunchHandler {
+        public Server() {
+            super(SERVER);
+        }
+    }
+
+    public static class ServerGameTest extends ForgeDevLaunchHandler {
+        public ServerGameTest() {
+            super(SERVER_GAMETEST);
+        }
+    }
+}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeGametestDevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeGametestDevLaunchHandler.java
deleted file mode 100644
index 2ce9e8ea93..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeGametestDevLaunchHandler.java
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.api.distmarker.Dist;
-
-public class ForgeGametestDevLaunchHandler extends CommonDevLaunchHandler {
-    @Override public String name() { return "forgegametestserverdev"; }
-    @Override public Dist getDist() { return Dist.DEDICATED_SERVER; }
-
-    @Override
-    public void devService(String[] arguments, ModuleLayer layer) throws Throwable {
-        Class.forName(layer.findModule("forge").orElseThrow(), "net.minecraftforge.gametest.GameTestMain").getMethod("main", String[].class).invoke(null, (Object)arguments);
-    }
-}
\ No newline at end of file
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeGametestUserdevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeGametestUserdevLaunchHandler.java
deleted file mode 100644
index 3ada4f71da..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeGametestUserdevLaunchHandler.java
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.api.distmarker.Dist;
-
-public class ForgeGametestUserdevLaunchHandler extends ForgeUserdevLaunchHandler {
-    @Override public String name() { return "forgegametestserveruserdev"; }
-    @Override public Dist getDist() { return Dist.DEDICATED_SERVER; }
-
-    @Override
-    public void devService(String[] arguments, ModuleLayer layer) throws Throwable {
-        Class.forName(layer.findModule("forge").orElseThrow(), "net.minecraftforge.gametest.GameTestMain").getMethod("main", String[].class).invoke(null, (Object)arguments);
-    }
-}
\ No newline at end of file
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeProdLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeProdLaunchHandler.java
new file mode 100644
index 0000000000..feac79b85d
--- /dev/null
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeProdLaunchHandler.java
@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.fml.loading.targets;
+
+import java.nio.file.Path;
+import java.util.List;
+import java.util.function.BiPredicate;
+
+import org.jetbrains.annotations.ApiStatus;
+
+import cpw.mods.jarhandling.SecureJar;
+import net.minecraftforge.fml.loading.FMLLoader;
+import net.minecraftforge.fml.loading.LibraryFinder;
+import net.minecraftforge.fml.loading.VersionInfo;
+
+@ApiStatus.Internal
+abstract class ForgeProdLaunchHandler extends CommonLaunchHandler {
+    protected ForgeProdLaunchHandler(LaunchType type) {
+        super(type, "forge_");
+    }
+
+    @Override public String getNaming() { return "srg"; }
+    @Override public boolean isProduction() { return true; }
+
+    protected Path mvn(VersionInfo info, String artifact) {
+        return mvn(info, artifact, "");
+    }
+    protected Path mvn(VersionInfo info, String artifact, String classifier) {
+        return mvn(info.forgeGroup(), artifact, classifier, info.mcAndForgeVersion());
+    }
+    protected Path mvn(String group, String artifact, String classifier, String version) {
+        return LibraryFinder.findPathForMaven(group, artifact, "", classifier, version);
+    }
+
+    @Override
+    public LocatedPaths getMinecraftPaths() {
+        var vers = FMLLoader.versionInfo();
+
+        // Minecraft
+        var mc = getMCPaths(vers);
+
+        // mods (Forge)
+        var forgejar     = mvn(vers, "forge", "universal");
+
+        // Libraries
+        var fmlcore      = mvn(vers, "fmlcore");
+        var javafmllang  = mvn(vers, "javafmllanguage");
+        var lowcodelang  = mvn(vers, "lowcodelanguage");
+        var mclang       = mvn(vers, "mclanguage");
+
+        return new LocatedPaths(
+            mc,
+            null,
+            List.of(List.of(forgejar)),
+            List.of(fmlcore, javafmllang, lowcodelang, mclang)
+        );
+    }
+
+    protected abstract List<Path> getMCPaths(VersionInfo vers);
+
+    public static class Client extends ForgeProdLaunchHandler {
+        public Client() {
+            super(CLIENT);
+        }
+
+        @Override
+        protected List<Path> getMCPaths(VersionInfo vers) {
+            var mc      = mvn("net.minecraft", "client", "srg", vers.mcAndMCPVersion());
+            var mcextra = mvn("net.minecraft", "client", "extra", vers.mcAndMCPVersion());
+            var patches = mvn(vers, "forge", "client");
+            return List.of(mc, mcextra, patches);
+        }
+    }
+    public static class Server extends ForgeProdLaunchHandler {
+        public Server() {
+            super(SERVER);
+        }
+
+        @Override
+        protected List<Path> getMCPaths(VersionInfo vers) {
+            var mc      = mvn("net.minecraft", "server", "srg", vers.mcAndMCPVersion());
+            var mcextra = mvn("net.minecraft", "server", "extra", vers.mcAndMCPVersion());
+            var patches = mvn(vers, "forge", "server");
+
+            // TODO: Get rid of this by filtering the file at install time.
+            // We only want it for it's resources. So filter everything else out.
+            BiPredicate<String, String> filter = (path, base) -> {
+                return path.equals("META-INF/versions/") || // This is required because it bypasses our filter for the manifest, and it's a multi-release jar.
+                      (!path.endsWith(".class") && !path.startsWith("META-INF/"));
+            };
+            mcextra = SecureJar.from(filter, mcextra).getRootPath();
+
+            return List.of(mc, mcextra, patches);
+        }
+    }
+}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerDevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerDevLaunchHandler.java
deleted file mode 100644
index 85f9fd9e84..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerDevLaunchHandler.java
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.api.distmarker.Dist;
-
-public class ForgeServerDevLaunchHandler extends CommonDevLaunchHandler {
-    @Override public String name() { return "forgeserverdev"; }
-    @Override public Dist getDist() { return Dist.DEDICATED_SERVER; }
-
-    @Override
-    public void devService(String[] arguments, ModuleLayer layer) throws Throwable {
-        serverService(arguments, layer);
-    }
-}
\ No newline at end of file
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerLaunchHandler.java
deleted file mode 100644
index a013f618b8..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerLaunchHandler.java
+++ /dev/null
@@ -1,28 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import cpw.mods.modlauncher.api.ILaunchHandlerService;
-import net.minecraftforge.fml.loading.LibraryFinder;
-import net.minecraftforge.fml.loading.VersionInfo;
-
-import java.nio.file.Path;
-import java.util.List;
-import java.util.function.BiPredicate;
-import java.util.stream.Stream;
-
-public class ForgeServerLaunchHandler extends CommonServerLaunchHandler implements ILaunchHandlerService {
-    @Override public String name() { return "forgeserver"; }
-
-    @Override
-    protected BiPredicate<String, String> processMCStream(VersionInfo versionInfo, Stream.Builder<Path> mc, BiPredicate<String, String> filter, Stream.Builder<List<Path>> mods) {
-        var forgepatches = LibraryFinder.findPathForMaven(versionInfo.forgeGroup(), "forge", "", "server", versionInfo.mcAndForgeVersion());
-        var forgejar = LibraryFinder.findPathForMaven(versionInfo.forgeGroup(), "forge", "", "universal", versionInfo.mcAndForgeVersion());
-        mc.add(forgepatches);
-        mods.add(List.of(forgejar));
-        return filter;
-    }
-}
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerUserdevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerUserdevLaunchHandler.java
deleted file mode 100644
index b33cc67f32..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeServerUserdevLaunchHandler.java
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.loading.targets;
-
-import net.minecraftforge.api.distmarker.Dist;
-
-public class ForgeServerUserdevLaunchHandler extends ForgeUserdevLaunchHandler {
-    @Override public String name() { return "forgeserveruserdev"; }
-    @Override public Dist getDist() { return Dist.DEDICATED_SERVER; }
-
-    @Override
-    public void devService(String[] arguments, ModuleLayer layer) throws Throwable {
-        serverService(arguments, layer);
-    }
-}
\ No newline at end of file
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeUserdevLaunchHandler.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeUserdevLaunchHandler.java
index 27925e9fa6..60b292348d 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeUserdevLaunchHandler.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/targets/ForgeUserdevLaunchHandler.java
@@ -5,16 +5,70 @@
 
 package net.minecraftforge.fml.loading.targets;
 
-import net.minecraftforge.fml.loading.VersionInfo;
-
+import net.minecraftforge.fml.loading.FMLLoader;
+import java.io.File;
 import java.nio.file.Path;
 import java.util.List;
+import java.util.Objects;
 import java.util.stream.Stream;
 
-public abstract class ForgeUserdevLaunchHandler extends CommonUserdevLaunchHandler {
+import org.jetbrains.annotations.ApiStatus;
+
+@ApiStatus.Internal
+abstract class ForgeUserdevLaunchHandler extends CommonDevLaunchHandler {
+    private ForgeUserdevLaunchHandler(LaunchType type) {
+        super(type, "forge_userdev_");
+    }
+
     @Override
-    protected void processStreams(String[] classpath, VersionInfo versionInfo, Stream.Builder<Path> mc, Stream.Builder<List<Path>> mods) {
-        var forge = findJarOnClasspath(classpath, "forge-" + versionInfo.mcAndForgeVersion());
-        mc.add(forge);
+    public LocatedPaths getMinecraftPaths() {
+        var legacyCP = Objects.requireNonNull(System.getProperty("legacyClassPath"), "Missing legacyClassPath, cannot find userdev jars").split(File.pathSeparator);
+        var vers = FMLLoader.versionInfo();
+
+        // Minecraft is extra jar {resources} + forge jar {patches}
+        // The MC extra and forge jars are on the classpath, so try and pull them out
+        var extra = findJarOnClasspath(legacyCP, "client-extra");
+        var forge = findJarOnClasspath(legacyCP, "forge-" + vers.mcAndForgeVersion());
+        // We need to filter the forge jar to just MC code
+        var filter = getMcFilter(extra, List.of(forge));
+
+        // Mods is forge classes + anything from MOD_CLASSES
+        var modstream = Stream.<List<Path>>builder();
+        // We want the forge as a seperate mod jar.
+        var forgemod = this.getForgeMod(List.of(forge));
+        modstream.add(List.of(forgemod));
+        // Mod code is in exploded directories
+        getModClasses().forEach((modid, paths) -> modstream.add(paths));
+
+        return new LocatedPaths(
+            List.of(forge, extra),
+            filter,
+            modstream.build().toList(),
+            getLibraries(legacyCP)
+        );
+    }
+
+    public static class Client extends ForgeUserdevLaunchHandler {
+        public Client() {
+            super(CLIENT);
+        }
+    }
+
+    public static class Data extends ForgeUserdevLaunchHandler {
+        public Data() {
+            super(DATA);
+        }
+    }
+
+    public static class Server extends ForgeUserdevLaunchHandler {
+        public Server() {
+            super(SERVER);
+        }
+    }
+
+    public static class ServerGameTest extends ForgeUserdevLaunchHandler {
+        public ServerGameTest() {
+            super(SERVER_GAMETEST);
+        }
     }
 }
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/loading/toposort/CyclePresentException.java b/fmlloader/src/main/java/net/minecraftforge/fml/loading/toposort/CyclePresentException.java
index e3167e3f5f..31175f5e3c 100644
--- a/fmlloader/src/main/java/net/minecraftforge/fml/loading/toposort/CyclePresentException.java
+++ b/fmlloader/src/main/java/net/minecraftforge/fml/loading/toposort/CyclePresentException.java
@@ -11,6 +11,7 @@ import java.util.Set;
  * An exception thrown for graphs with cycles as an argument for topological sort.
  */
 public final class CyclePresentException extends IllegalArgumentException {
+    private static final long serialVersionUID = -2609660010927054667L;
     private final Set<Set<?>> cycles;
 
     /**
diff --git a/fmlloader/src/main/java/net/minecraftforge/fml/server/ServerMain.java b/fmlloader/src/main/java/net/minecraftforge/fml/server/ServerMain.java
deleted file mode 100644
index 2cef0ac850..0000000000
--- a/fmlloader/src/main/java/net/minecraftforge/fml/server/ServerMain.java
+++ /dev/null
@@ -1,68 +0,0 @@
-/*
- * Copyright (c) Forge Development LLC and contributors
- * SPDX-License-Identifier: LGPL-2.1-only
- */
-
-package net.minecraftforge.fml.server;
-
-import cpw.mods.modlauncher.InvalidLauncherSetupException;
-import cpw.mods.modlauncher.Launcher;
-
-import java.io.File;
-import java.io.IOException;
-import java.net.URISyntaxException;
-import java.net.URL;
-import java.security.CodeSource;
-import java.security.ProtectionDomain;
-import java.util.Optional;
-import java.util.jar.JarFile;
-import java.util.jar.Manifest;
-
-public class ServerMain {
-    public static void main(String[] args) {
-        try {
-            Class.forName("cpw.mods.modlauncher.Launcher", false, ClassLoader.getSystemClassLoader());
-            Class.forName("net.minecraftforge.forgespi.Environment", false, ClassLoader.getSystemClassLoader());
-        } catch (ClassNotFoundException cnfe) {
-            System.err.println("FATAL ERROR, You need to run the installer. The libraries required to launch a server are missing");
-            System.exit(1);
-        }
-
-        final String launchArgs = Optional.ofNullable(ServerMain.class.getProtectionDomain()).
-                map(ProtectionDomain::getCodeSource).
-                map(CodeSource::getLocation).
-                map(ServerMain::urlToManifest).
-                map(Manifest::getMainAttributes).
-                map(a -> a.getValue("ServerLaunchArgs")).
-                orElseThrow(ServerMain::throwMissingManifest);
-        String[] defaultargs = launchArgs.split(" ");
-        String[] result = new String[args.length + defaultargs.length];
-        System.arraycopy(defaultargs, 0, result, 0, defaultargs.length);
-        System.arraycopy(args, 0, result, defaultargs.length, args.length);
-        // separate class, so the exception can resolve
-        new Runner().runLauncher(result);
-    }
-
-    private static class Runner {
-        private void runLauncher(final String[] result) {
-            try {
-                Launcher.main(result);
-            } catch (InvalidLauncherSetupException e) {
-                System.err.println("The server is missing critical libraries and cannot load. Please run the installer to correct this");
-                System.exit(1);
-            }
-        }
-    }
-    private static Manifest urlToManifest(URL url) {
-        try {
-            return new JarFile(new File(url.toURI())).getManifest();
-        } catch (URISyntaxException | IOException e) {
-            return null;
-        }
-    }
-
-    private static RuntimeException throwMissingManifest() {
-        System.err.println("This is not being run from a valid JAR file, essential data is missing.");
-        return new RuntimeException("Missing the manifest");
-    }
-}
diff --git a/fmlloader/src/main/resources/META-INF/services/cpw.mods.cl.ModularURLHandler.IURLProvider b/fmlloader/src/main/resources/META-INF/services/cpw.mods.cl.ModularURLHandler.IURLProvider
deleted file mode 100644
index e69de29bb2..0000000000
diff --git a/fmlloader/src/main/resources/META-INF/services/cpw.mods.modlauncher.api.ILaunchHandlerService b/fmlloader/src/main/resources/META-INF/services/cpw.mods.modlauncher.api.ILaunchHandlerService
index f0cc3caef5..b4a3ffa7bc 100644
--- a/fmlloader/src/main/resources/META-INF/services/cpw.mods.modlauncher.api.ILaunchHandlerService
+++ b/fmlloader/src/main/resources/META-INF/services/cpw.mods.modlauncher.api.ILaunchHandlerService
@@ -1,10 +1,15 @@
-net.minecraftforge.fml.loading.targets.ForgeClientLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeClientDevLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeClientUserdevLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeServerLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeServerDevLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeServerUserdevLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeDataDevLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeDataUserdevLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeGametestDevLaunchHandler
-net.minecraftforge.fml.loading.targets.ForgeGametestUserdevLaunchHandler
+# Production
+net.minecraftforge.fml.loading.targets.ForgeProdLaunchHandler$Client
+net.minecraftforge.fml.loading.targets.ForgeProdLaunchHandler$Server
+
+# Mod Developers
+net.minecraftforge.fml.loading.targets.ForgeUserdevLaunchHandler$Client
+net.minecraftforge.fml.loading.targets.ForgeUserdevLaunchHandler$Data
+net.minecraftforge.fml.loading.targets.ForgeUserdevLaunchHandler$Server
+net.minecraftforge.fml.loading.targets.ForgeUserdevLaunchHandler$ServerGameTest
+
+#Working on Forge itself
+net.minecraftforge.fml.loading.targets.ForgeDevLaunchHandler$Client
+net.minecraftforge.fml.loading.targets.ForgeDevLaunchHandler$Data
+net.minecraftforge.fml.loading.targets.ForgeDevLaunchHandler$Server
+net.minecraftforge.fml.loading.targets.ForgeDevLaunchHandler$ServerGameTest
diff --git a/src/generated_test/resources/EMPTY b/src/generated_test/resources/EMPTY
deleted file mode 100644
index e69de29bb2..0000000000
diff --git a/src/generated_test/resources/pack.mcmeta b/src/generated_test/resources/empty/pack.mcmeta
similarity index 100%
rename from src/generated_test/resources/pack.mcmeta
rename to src/generated_test/resources/empty/pack.mcmeta
diff --git a/src/generated_test/resources/data/forge/loot_modifiers/global_loot_modifiers.json b/src/generated_test/resources/global_loot_test/data/forge/loot_modifiers/global_loot_modifiers.json
similarity index 100%
rename from src/generated_test/resources/data/forge/loot_modifiers/global_loot_modifiers.json
rename to src/generated_test/resources/global_loot_test/data/forge/loot_modifiers/global_loot_modifiers.json
diff --git a/src/generated_test/resources/data/global_loot_test/loot_modifiers/bamboo_silk.json b/src/generated_test/resources/global_loot_test/data/global_loot_test/loot_modifiers/bamboo_silk.json
similarity index 100%
rename from src/generated_test/resources/data/global_loot_test/loot_modifiers/bamboo_silk.json
rename to src/generated_test/resources/global_loot_test/data/global_loot_test/loot_modifiers/bamboo_silk.json
diff --git a/src/generated_test/resources/data/global_loot_test/loot_modifiers/dungeon_loot.json b/src/generated_test/resources/global_loot_test/data/global_loot_test/loot_modifiers/dungeon_loot.json
similarity index 100%
rename from src/generated_test/resources/data/global_loot_test/loot_modifiers/dungeon_loot.json
rename to src/generated_test/resources/global_loot_test/data/global_loot_test/loot_modifiers/dungeon_loot.json
diff --git a/src/generated_test/resources/data/global_loot_test/loot_modifiers/smelting.json b/src/generated_test/resources/global_loot_test/data/global_loot_test/loot_modifiers/smelting.json
similarity index 100%
rename from src/generated_test/resources/data/global_loot_test/loot_modifiers/smelting.json
rename to src/generated_test/resources/global_loot_test/data/global_loot_test/loot_modifiers/smelting.json
diff --git a/src/generated_test/resources/data/global_loot_test/loot_modifiers/wheat_harvest.json b/src/generated_test/resources/global_loot_test/data/global_loot_test/loot_modifiers/wheat_harvest.json
similarity index 100%
rename from src/generated_test/resources/data/global_loot_test/loot_modifiers/wheat_harvest.json
rename to src/generated_test/resources/global_loot_test/data/global_loot_test/loot_modifiers/wheat_harvest.json
diff --git a/src/generated_mdk/resources/pack.mcmeta b/src/generated_test/resources/mdk_datagen/pack.mcmeta
similarity index 79%
rename from src/generated_mdk/resources/pack.mcmeta
rename to src/generated_test/resources/mdk_datagen/pack.mcmeta
index eca79ae4ae..2a62706c90 100644
--- a/src/generated_mdk/resources/pack.mcmeta
+++ b/src/generated_test/resources/mdk_datagen/pack.mcmeta
@@ -3,6 +3,6 @@
     "description": {
       "text": "${mod_id} resources"
     },
-    "pack_format": 15
+    "pack_format": 18
   }
 }
\ No newline at end of file
diff --git a/src/main/java/net/minecraftforge/client/ForgeHooksClient.java b/src/main/java/net/minecraftforge/client/ForgeHooksClient.java
index a826efb21e..913ac60acb 100644
--- a/src/main/java/net/minecraftforge/client/ForgeHooksClient.java
+++ b/src/main/java/net/minecraftforge/client/ForgeHooksClient.java
@@ -20,7 +20,6 @@ import net.minecraft.FileUtil;
 import net.minecraft.client.Camera;
 import net.minecraft.client.KeyMapping;
 import net.minecraft.client.Minecraft;
-import net.minecraft.client.MouseHandler;
 import net.minecraft.client.Options;
 import net.minecraft.client.color.block.BlockColors;
 import net.minecraft.client.color.item.ItemColors;
@@ -60,7 +59,6 @@ import net.minecraft.client.renderer.texture.SpriteContents;
 import net.minecraft.client.renderer.texture.TextureAtlas;
 import net.minecraft.client.renderer.texture.TextureAtlasSprite;
 import net.minecraft.client.resources.language.I18n;
-import net.minecraft.client.resources.metadata.animation.AnimationMetadataSection;
 import net.minecraft.client.resources.metadata.animation.FrameSize;
 import net.minecraft.client.resources.model.BakedModel;
 import net.minecraft.client.resources.model.Material;
@@ -76,12 +74,10 @@ import net.minecraft.network.chat.ChatType;
 import net.minecraft.network.chat.ChatTypeDecoration;
 import net.minecraft.network.chat.CommonComponents;
 import net.minecraft.network.chat.Component;
-import net.minecraft.network.chat.ComponentContents;
 import net.minecraft.network.chat.FormattedText;
 import net.minecraft.network.chat.PlayerChatMessage;
 import net.minecraft.network.chat.Style;
 import net.minecraft.network.protocol.status.ServerStatus;
-import net.minecraft.resources.ResourceKey;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.server.packs.resources.ReloadableResourceManager;
 import net.minecraft.server.packs.resources.Resource;
@@ -97,10 +93,8 @@ import net.minecraft.world.entity.LivingEntity;
 import net.minecraft.world.entity.ai.attributes.AttributeInstance;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.inventory.tooltip.TooltipComponent;
-import net.minecraft.world.item.CreativeModeTab;
 import net.minecraft.world.item.ItemDisplayContext;
 import net.minecraft.world.item.ItemStack;
-import net.minecraft.world.item.ItemStackLinkedSet;
 import net.minecraft.world.item.crafting.RecipeManager;
 import net.minecraft.world.level.BlockAndTintGetter;
 import net.minecraft.world.level.GameType;
@@ -151,12 +145,9 @@ import net.minecraftforge.client.model.data.ModelData;
 import net.minecraftforge.client.textures.ForgeTextureMetadata;
 import net.minecraftforge.client.textures.TextureAtlasSpriteLoaderManager;
 import net.minecraftforge.common.ForgeConfig;
-import net.minecraftforge.common.ForgeHooks;
 import net.minecraftforge.common.ForgeI18n;
 import net.minecraftforge.common.ForgeMod;
 import net.minecraftforge.common.MinecraftForge;
-import net.minecraftforge.common.util.MutableHashedLinkedMap;
-import net.minecraftforge.event.BuildCreativeModeTabContentsEvent;
 import net.minecraftforge.eventbus.api.Event;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.IExtensionPoint;
diff --git a/src/main/java/net/minecraftforge/client/gui/overlay/VanillaGuiOverlay.java b/src/main/java/net/minecraftforge/client/gui/overlay/VanillaGuiOverlay.java
index 2de2168562..19011d0d4f 100644
--- a/src/main/java/net/minecraftforge/client/gui/overlay/VanillaGuiOverlay.java
+++ b/src/main/java/net/minecraftforge/client/gui/overlay/VanillaGuiOverlay.java
@@ -23,6 +23,7 @@ import org.lwjgl.opengl.GL11;
 /**
  * All the vanilla {@linkplain IGuiOverlay HUD overlays} in the order that they render.
  */
+@SuppressWarnings("resource")
 public enum VanillaGuiOverlay {
     VIGNETTE("vignette", (gui, guiGraphics, partialTick, screenWidth, screenHeight) -> {
         if (Minecraft.useFancyGraphics()) {
diff --git a/src/main/java/net/minecraftforge/data/loading/DatagenModLoader.java b/src/main/java/net/minecraftforge/data/loading/DatagenModLoader.java
index 7f49f3c437..ae0f138922 100644
--- a/src/main/java/net/minecraftforge/data/loading/DatagenModLoader.java
+++ b/src/main/java/net/minecraftforge/data/loading/DatagenModLoader.java
@@ -6,10 +6,10 @@
 package net.minecraftforge.data.loading;
 
 import net.minecraft.Util;
-import net.minecraft.core.HolderLookup;
 import net.minecraft.data.registries.VanillaRegistries;
 import net.minecraft.server.Bootstrap;
 import net.minecraftforge.common.data.ExistingFileHelper;
+import net.minecraftforge.fml.ModList;
 import net.minecraftforge.fml.ModLoader;
 import net.minecraftforge.fml.ModWorkManager;
 import net.minecraftforge.data.event.GatherDataEvent;
@@ -19,12 +19,13 @@ import org.apache.logging.log4j.Logger;
 import java.io.File;
 import java.nio.file.Path;
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.Set;
 import java.util.concurrent.CompletableFuture;
+import java.util.regex.Pattern;
 
 public class DatagenModLoader {
     private static final Logger LOGGER = LogManager.getLogger();
-    private static GatherDataEvent.DataGeneratorConfig dataGeneratorConfig;
     private static ExistingFileHelper existingFileHelper;
     private static boolean runningDataGen;
 
@@ -32,25 +33,49 @@ public class DatagenModLoader {
         return runningDataGen;
     }
 
-    public static void begin(final Set<String> mods, final Path path, final Collection<Path> inputs, Collection<Path> existingPacks,
-            Set<String> existingMods, final boolean serverGenerators, final boolean clientGenerators, final boolean devToolGenerators, final boolean reportsGenerator,
-            final boolean structureValidator, final boolean flat, final String assetIndex, final File assetsDir) {
-        if (mods.contains("minecraft") && mods.size() == 1)
+    public static void begin(
+        Set<String> patterns, Path output, Collection<Path> inputs, Collection<Path> existingPacks, Set<String> existingMods,
+        boolean genServer, boolean genClient, boolean genDev, boolean genReports,
+        boolean validate, boolean flat, String assetIndex, File assetsDir
+    ) {
+        if (patterns.contains("minecraft") && patterns.size() == 1)
             return;
-        LOGGER.info("Initializing Data Gatherer for mods {}", mods);
+
         runningDataGen = true;
         Bootstrap.bootStrap();
         ModLoader.get().gatherAndInitializeMods(ModWorkManager.syncExecutor(), ModWorkManager.parallelExecutor(), ()->{});
-        CompletableFuture<HolderLookup.Provider> lookupProvider = CompletableFuture.supplyAsync(VanillaRegistries::createLookup, Util.backgroundExecutor());
-        dataGeneratorConfig = new GatherDataEvent.DataGeneratorConfig(mods, path, inputs, lookupProvider, serverGenerators,
-                clientGenerators, devToolGenerators, reportsGenerator, structureValidator, flat);
+        var lookupProvider = CompletableFuture.supplyAsync(VanillaRegistries::createLookup, Util.backgroundExecutor());
+
+        var mods = new HashSet<String>();
+        for (var pattern : patterns) {
+            if (pattern.indexOf('.') == -1) // No wildcard!
+                mods.add(pattern);
+
+            var m = Pattern.compile('^' + pattern + '$');
+            ModList.get().forEachModInOrder(mc -> {
+                var id = mc.getModId();
+                if (!"forge".equals(id) && !"minecraft".equals(id) && m.matcher(id).matches())
+                    mods.add(id);
+            });
+        }
+        LOGGER.info("Initializing Data Gatherer for mods {}", mods);
+
+        var config = new GatherDataEvent.DataGeneratorConfig(mods, output, inputs, lookupProvider, genServer,
+                genClient, genDev, genReports, validate, flat);
+
         if (!mods.contains("forge")) {
             // If we aren't generating data for forge, automatically add forge as an existing so mods can access forge's data
             existingMods.add("forge");
         }
-        existingFileHelper = new ExistingFileHelper(existingPacks, existingMods, structureValidator, assetIndex, assetsDir);
-        ModLoader.get().runEventGenerator(mc -> new GatherDataEvent(mc, dataGeneratorConfig.makeGenerator(p -> dataGeneratorConfig.isFlat() ? p : p.resolve(mc.getModId()),
-                dataGeneratorConfig.getMods().contains(mc.getModId())), dataGeneratorConfig, existingFileHelper));
-        dataGeneratorConfig.runAll();
+
+        existingFileHelper = new ExistingFileHelper(existingPacks, existingMods, validate, assetIndex, assetsDir);
+        ModLoader.get().runEventGenerator(mc -> new GatherDataEvent(
+            mc,
+            config.makeGenerator(
+                p -> config.isFlat() ? p : p.resolve(mc.getModId()),
+                config.getMods().contains(mc.getModId())
+            ), config, existingFileHelper)
+        );
+        config.runAll();
     }
 }
diff --git a/src/main/java/net/minecraftforge/event/AddReloadListenerEvent.java b/src/main/java/net/minecraftforge/event/AddReloadListenerEvent.java
index 84e9f2bb85..d394fed423 100644
--- a/src/main/java/net/minecraftforge/event/AddReloadListenerEvent.java
+++ b/src/main/java/net/minecraftforge/event/AddReloadListenerEvent.java
@@ -27,14 +27,12 @@ import java.util.concurrent.Executor;
  * The event is fired on each reload and lets modders add their own ReloadListeners, for server-side resources.
  * The event is fired on the {@link MinecraftForge#EVENT_BUS}
  */
-public class AddReloadListenerEvent extends Event
-{
+public class AddReloadListenerEvent extends Event {
     private final List<PreparableReloadListener> listeners = new ArrayList<>();
     private final ReloadableServerResources serverResources;
     private final RegistryAccess registryAccess;
 
-    public AddReloadListenerEvent(ReloadableServerResources serverResources, RegistryAccess registryAccess)
-    {
+    public AddReloadListenerEvent(ReloadableServerResources serverResources, RegistryAccess registryAccess) {
         this.serverResources = serverResources;
         this.registryAccess = registryAccess;
     }
@@ -42,21 +40,18 @@ public class AddReloadListenerEvent extends Event
    /**
     * @param listener the listener to add to the ResourceManager on reload
     */
-    public void addListener(PreparableReloadListener listener)
-    {
+    public void addListener(PreparableReloadListener listener) {
        listeners.add(new WrappedStateAwareListener(listener));
     }
 
-    public List<PreparableReloadListener> getListeners()
-    {
+    public List<PreparableReloadListener> getListeners() {
        return ImmutableList.copyOf(listeners);
     }
 
     /**
      * @return The ReloableServerResources being reloaded.
      */
-    public ReloadableServerResources getServerResources()
-    {
+    public ReloadableServerResources getServerResources() {
         return serverResources;
     }
 
@@ -64,8 +59,7 @@ public class AddReloadListenerEvent extends Event
      * This context object holds data relevant to the current reload, such as staged tags.
      * @return The condition context for the currently active reload.
      */
-    public ICondition.IContext getConditionContext()
-    {
+    public ICondition.IContext getConditionContext() {
         return serverResources.getConditionContext();
     }
 
@@ -74,8 +68,7 @@ public class AddReloadListenerEvent extends Event
      * All built-in and dynamic registries are loaded and frozen by this point.
      * @return The RegistryAccess context for the currently active reload.
      */
-    public RegistryAccess getRegistryAccess()
-    {
+    public RegistryAccess getRegistryAccess() {
         return registryAccess;
     }
 
diff --git a/src/test/java/net/minecraftforge/debug/CreativeModeTabTest.java b/src/test/java/net/minecraftforge/debug/creativetabs/CreativeModeTabTest.java
similarity index 99%
rename from src/test/java/net/minecraftforge/debug/CreativeModeTabTest.java
rename to src/test/java/net/minecraftforge/debug/creativetabs/CreativeModeTabTest.java
index dd3d4cc821..2033c0b745 100644
--- a/src/test/java/net/minecraftforge/debug/CreativeModeTabTest.java
+++ b/src/test/java/net/minecraftforge/debug/creativetabs/CreativeModeTabTest.java
@@ -3,7 +3,7 @@
  * SPDX-License-Identifier: LGPL-2.1-only
  */
 
-package net.minecraftforge.debug;
+package net.minecraftforge.debug.creativetabs;
 
 import java.util.List;
 import net.minecraft.core.registries.Registries;
diff --git a/src/test/java/net/minecraftforge/debug/gameplay/loot/GlobalLootModifiersTest.java b/src/test/java/net/minecraftforge/debug/gameplay/loot/GlobalLootModifiersTest.java
index c409a712da..ba2f14d752 100644
--- a/src/test/java/net/minecraftforge/debug/gameplay/loot/GlobalLootModifiersTest.java
+++ b/src/test/java/net/minecraftforge/debug/gameplay/loot/GlobalLootModifiersTest.java
@@ -90,7 +90,7 @@ public class GlobalLootModifiersTest {
         var entries = event.getEntries();
         var vis = TabVisibility.PARENT_AND_SEARCH_TABS;
         if (event.getTabKey() == Empty.TAB) {
-            var smelt = new ItemStack(Items.SHEARS);
+            var smelt = new ItemStack(Items.IRON_AXE);
             EnchantmentHelper.setEnchantments(ImmutableMap.<Enchantment, Integer>builder().put(SMELT.get(), 1).build(), smelt);
             entries.put(smelt, vis);
         }
diff --git a/src/test_old/java/net/minecraftforge/mdk/MdkDatagen.java b/src/test/java/net/minecraftforge/mdk/Datagen.java
similarity index 86%
rename from src/test_old/java/net/minecraftforge/mdk/MdkDatagen.java
rename to src/test/java/net/minecraftforge/mdk/Datagen.java
index 63f820bfd7..c4535ac36a 100644
--- a/src/test_old/java/net/minecraftforge/mdk/MdkDatagen.java
+++ b/src/test/java/net/minecraftforge/mdk/Datagen.java
@@ -16,18 +16,15 @@ import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
 
 import java.util.Optional;
 
-@Mod(MdkDatagen.MOD_ID)
-public class MdkDatagen
-{
+@Mod(Datagen.MOD_ID)
+public class Datagen {
     static final String MOD_ID = "mdk_datagen";
 
-    public MdkDatagen()
-    {
-        FMLJavaModLoadingContext.get().getModEventBus().addListener(MdkDatagen::gatherData);
+    public Datagen() {
+        FMLJavaModLoadingContext.get().getModEventBus().addListener(Datagen::gatherData);
     }
 
-    private static void gatherData(GatherDataEvent event)
-    {
+    private static void gatherData(GatherDataEvent event) {
         var gen = event.getGenerator();
         var packOutput = gen.getPackOutput();
         gen.addProvider(true, new PackMetadataGenerator(packOutput)
diff --git a/src/test/resources/META-INF/mods.toml b/src/test/resources/global_loot_test/META-INF/mods.toml
similarity index 52%
rename from src/test/resources/META-INF/mods.toml
rename to src/test/resources/global_loot_test/META-INF/mods.toml
index 56730474a7..a7bf4e2486 100644
--- a/src/test/resources/META-INF/mods.toml
+++ b/src/test/resources/global_loot_test/META-INF/mods.toml
@@ -1,15 +1,3 @@
-modLoader="javafml"
-loaderVersion="[28,)"
-license="LGPL v2.1"
-
-[[mods]]
-modId="empty"
-
-[[mods]]
-modId="creative_mode_tab_test"
-
-
-
 [[mods]]
 modId="global_loot_test"
 [[dependencies.global_loot_test]]