diff --git a/build.sbt b/build.sbt
index bbe4e0e39..6517ba273 100644
--- a/build.sbt
+++ b/build.sbt
@@ -114,6 +114,7 @@ lazy val core = projectMatrix
       "smithy.waiters",
       "smithy4s.api"
     ),
+    genDiscoverModels := true,
     Compile / sourceGenerators := Seq(genSmithyScala(Compile).taskValue),
     Compile / sourceGenerators += sourceDirectory
       .map(Boilerplate.gen(_, Boilerplate.BoilerplateModule.Core))
@@ -140,18 +141,15 @@ lazy val core = projectMatrix
       (ThisBuild / baseDirectory).value / "sampleSpecs" / "adtMember.smithy"
     ),
     (Test / sourceGenerators) := Seq(genSmithyScala(Test).taskValue),
-    testFrameworks += new TestFramework("weaver.framework.CatsEffect")
-    // TODO: bring back
-    // Compile / packageSrc / mappings ++= {
-    //   val base = (Compile / sourceManaged).value
-    //   val files = (Compile / managedSources).value
-    //   files.map(f =>
-    //     (
-    //       f,
-    //       f.relativeTo(base).get.getPath
-    //     )
-    //   )
-    // }
+    testFrameworks += new TestFramework("weaver.framework.CatsEffect"),
+    Compile / packageSrc / mappings ++= {
+      val base = (Compile / sourceManaged).value
+      val files = (Compile / managedSources).value
+      files
+        .map(f => (f, f.relativeTo(base)))
+        // this excludes modules/core/src/generated/PartiallyAppliedStruct.scala
+        .collect { case (f, Some(relF)) => f -> relF.getPath() }
+    }
   )
   .jvmPlatform(allJvmScalaVersions, jvmDimSettings)
   .jsPlatform(allJsScalaVersions, jsDimSettings)
@@ -192,6 +190,7 @@ lazy val `aws-kernel` = projectMatrix
       Dependencies.Weaver.scalacheck.value % Test
     ),
     testFrameworks += new TestFramework("weaver.framework.CatsEffect"),
+    genDiscoverModels := true,
     Compile / allowedNamespaces := Seq(
       "aws.api",
       "aws.auth",
@@ -247,6 +246,7 @@ lazy val `aws-http4s` = projectMatrix
   .dependsOn(aws)
   .settings(
     isCE3 := true,
+    Test / genDiscoverModels := true,
     libraryDependencies ++= {
       Seq(
         Dependencies.Http4s.client.value,
@@ -272,16 +272,7 @@ lazy val codegen = projectMatrix
   .dependsOn(openapi)
   .jvmPlatform(buildtimejvmScala2Versions, jvmDimSettings)
   .settings(
-    buildInfoKeys := Seq[BuildInfoKey](
-      organization,
-      version,
-      scalaBinaryVersion,
-      "protocolArtifact" -> (protocol
-        .jvm(autoScalaLibrary = false) / moduleName).value,
-      "smithyOrg" -> Dependencies.Smithy.model.organization,
-      "smithyVersion" -> Dependencies.Smithy.model.revision,
-      "smithyArtifact" -> Dependencies.Smithy.model.name
-    ),
+    buildInfoKeys := Seq[BuildInfoKey](version, scalaBinaryVersion),
     buildInfoPackage := "smithy4s.codegen",
     isCE3 := true,
     libraryDependencies ++= Seq(
@@ -716,6 +707,7 @@ lazy val genSmithyOpenapiOutput = SettingKey[File]("genSmithyOpenapiOutput")
 lazy val allowedNamespaces = SettingKey[Seq[String]]("allowedNamespaces")
 lazy val genSmithyDependencies =
   SettingKey[Seq[String]]("genSmithyDependencies")
+lazy val genDiscoverModels = SettingKey[Boolean]("genDiscoverModels")
 
 (ThisBuild / smithySpecs) := Seq.empty
 
@@ -727,9 +719,6 @@ def genSmithyResources(config: Configuration) = genSmithyImpl(config).map(_._2)
  * library code, aws-specific code.
  */
 def genSmithyImpl(config: Configuration) = Def.task {
-  // codegen needs the `protocol` jar to be published
-  (protocol.jvm(autoScalaLibrary = false) / publishLocal).value
-
   val inputFiles = (config / smithySpecs).value
   val outputDir = (config / genSmithyOutput).?.value
     .getOrElse((config / sourceManaged).value)
@@ -741,6 +730,8 @@ def genSmithyImpl(config: Configuration) = Def.task {
   val allowedNS = (config / allowedNamespaces).?.value.filterNot(_.isEmpty)
   val smithyDeps =
     (config / genSmithyDependencies).?.value.getOrElse(List.empty)
+  val discoverModels =
+    (config / genDiscoverModels).?.value.getOrElse(false)
 
   val codegenCp =
     (`codegen-cli`.jvm(Smithy4sPlugin.Scala213) / Compile / fullClasspath).value
@@ -765,6 +756,7 @@ def genSmithyImpl(config: Configuration) = Def.task {
               val args =
                 List("--output", outputDir) ++
                   List("--openapi-output", openapiOutputDir) ++
+                  (if (discoverModels) List("--discover-models") else Nil) ++
                   (if (allowedNS.isDefined)
                      List("--allowed-ns", allowedNS.get.mkString(","))
                    else Nil) ++ inputs
diff --git a/modules/codegen-cli/src/smithy4s/codegen/cli/CodegenCommand.scala b/modules/codegen-cli/src/smithy4s/codegen/cli/CodegenCommand.scala
index 82fe64e38..74a543898 100644
--- a/modules/codegen-cli/src/smithy4s/codegen/cli/CodegenCommand.scala
+++ b/modules/codegen-cli/src/smithy4s/codegen/cli/CodegenCommand.scala
@@ -69,6 +69,15 @@ object CodegenCommand {
       )
       .orFalse
 
+  val discoverModelsOpt =
+    Opts
+      .flag(
+        long = "discover-models",
+        help =
+          "Indicates whether the model assembler should try to discover models in the classpath"
+      )
+      .orFalse
+
   val allowedNSOpt: Opts[Option[Set[String]]] =
     Opts
       .option[String](
@@ -93,6 +102,7 @@ object CodegenCommand {
       openApiOutputOpt,
       skipScalaOpt,
       skipOpenapiOpt,
+      discoverModelsOpt,
       allowedNSOpt,
       excludedNSOpt,
       repositoriesOpt,
@@ -102,7 +112,7 @@ object CodegenCommand {
     )
       .mapN {
         // format: off
-        case (output, openApiOutput, skipScala, skipOpenapi, allowedNS, excludedNS, repositories, dependencies, transformers, specsArgs) =>
+        case (output, openApiOutput, skipScala, skipOpenapi, discoverModels, allowedNS, excludedNS, repositories, dependencies, transformers, specsArgs) =>
         // format: on
           CodegenArgs(
             specsArgs,
@@ -110,6 +120,7 @@ object CodegenCommand {
             openApiOutput.getOrElse(os.pwd),
             skipScala,
             skipOpenapi,
+            discoverModels,
             allowedNS,
             excludedNS,
             repositories.getOrElse(List.empty),
diff --git a/modules/codegen-cli/src/smithy4s/codegen/cli/DumpModel.scala b/modules/codegen-cli/src/smithy4s/codegen/cli/DumpModel.scala
index 5423c611e..6bd846500 100644
--- a/modules/codegen-cli/src/smithy4s/codegen/cli/DumpModel.scala
+++ b/modules/codegen-cli/src/smithy4s/codegen/cli/DumpModel.scala
@@ -26,7 +26,8 @@ object DumpModel {
       args.specs.map(_.toIO).toSet,
       args.dependencies,
       args.repositories,
-      args.transformers
+      args.transformers,
+      discoverModels = false
     )
 
     Node.prettyPrintJson(ModelSerializer.builder().build.serialize(model))
diff --git a/modules/codegen-cli/test/src/smithy4s/codegen/cli/CommandParsingSpec.scala b/modules/codegen-cli/test/src/smithy4s/codegen/cli/CommandParsingSpec.scala
index b2a479ecb..bfb7ad399 100644
--- a/modules/codegen-cli/test/src/smithy4s/codegen/cli/CommandParsingSpec.scala
+++ b/modules/codegen-cli/test/src/smithy4s/codegen/cli/CommandParsingSpec.scala
@@ -31,6 +31,7 @@ object CommandParsingSpec extends FunSuite {
               openapiOutput = os.pwd,
               skipScala = false,
               skipOpenapi = false,
+              discoverModels = false,
               allowedNS = None,
               excludedNS = None,
               repositories = Nil,
@@ -77,6 +78,7 @@ object CommandParsingSpec extends FunSuite {
               openapiOutput = os.pwd / "target" / "openapi",
               skipScala = true,
               skipOpenapi = true,
+              discoverModels = false,
               allowedNS = Some(Set("name1", "name2")),
               excludedNS = None,
               repositories = List("repo1", "repo2"),
diff --git a/modules/codegen-plugin/src/smithy4s/codegen/CodegenPlugin.scala b/modules/codegen-plugin/src/smithy4s/codegen/CodegenPlugin.scala
index aa6e5c3c5..905871972 100644
--- a/modules/codegen-plugin/src/smithy4s/codegen/CodegenPlugin.scala
+++ b/modules/codegen-plugin/src/smithy4s/codegen/CodegenPlugin.scala
@@ -133,8 +133,8 @@ object Smithy4sCodegenPlugin extends AutoPlugin {
     * to decide whether or not Codegen should run.
     */
   def cachedSmithyCodegen(conf: Configuration) = Def.task {
-    val outputPath = (conf / smithy4sOutputDir).value.getAbsolutePath()
-    val openApiOutputPath = (conf / smithy4sOpenapiDir).value.getAbsolutePath()
+    val outputPath = (conf / smithy4sOutputDir).value
+    val openApiOutputPath = (conf / smithy4sOpenapiDir).value
     val allowedNamespaces =
       (conf / smithy4sAllowedNamespaces).?.value.map(_.toSet)
     val excludedNamespaces =
@@ -149,7 +149,7 @@ object Smithy4sCodegenPlugin extends AutoPlugin {
     val out = streams.value
     val cacheFile =
       out.cacheDirectory / s"smithy4s_${scalaBinaryVersion.value}"
-    
+
     // This is important - it's what re-triggers this task on file changes
     val _ = (conf / smithy4sCodegen).inputFileChanges
 
@@ -169,6 +169,7 @@ object Smithy4sCodegenPlugin extends AutoPlugin {
           openapiOutput = os.Path(openApiOutputPath),
           skipScala = false,
           skipOpenapi = false,
+          discoverModels = true, // we need protocol here
           allowedNS = allowedNamespaces,
           excludedNS = excludedNamespaces,
           repositories = res,
diff --git a/modules/codegen/src/smithy4s/codegen/Codegen.scala b/modules/codegen/src/smithy4s/codegen/Codegen.scala
index 89488d2f4..ee29305e2 100644
--- a/modules/codegen/src/smithy4s/codegen/Codegen.scala
+++ b/modules/codegen/src/smithy4s/codegen/Codegen.scala
@@ -31,7 +31,8 @@ object Codegen { self =>
       args.specs.map(_.toIO).toSet,
       args.dependencies,
       args.repositories,
-      args.transformers
+      args.transformers,
+      args.discoverModels
     )
 
     val scalaFiles = if (!args.skipScala) {
@@ -95,7 +96,8 @@ object Codegen { self =>
         Renderer(amended)
       }
       .map { result =>
-        val relPath = os.RelPath(result.namespace.replace('.', '/'))
+        val relPath =
+          os.RelPath(result.namespace.split('.').toIndexedSeq, ups = 0)
         (relPath, result.name, result.content)
       }
   }
diff --git a/modules/codegen/src/smithy4s/codegen/CodegenArgs.scala b/modules/codegen/src/smithy4s/codegen/CodegenArgs.scala
index 7cb2a2089..552990647 100644
--- a/modules/codegen/src/smithy4s/codegen/CodegenArgs.scala
+++ b/modules/codegen/src/smithy4s/codegen/CodegenArgs.scala
@@ -22,6 +22,7 @@ case class CodegenArgs(
     openapiOutput: os.Path,
     skipScala: Boolean,
     skipOpenapi: Boolean,
+    discoverModels: Boolean,
     allowedNS: Option[Set[String]],
     excludedNS: Option[Set[String]],
     repositories: List[String],
diff --git a/modules/codegen/src/smithy4s/codegen/ModelLoader.scala b/modules/codegen/src/smithy4s/codegen/ModelLoader.scala
index a6446c841..4b7f8debf 100644
--- a/modules/codegen/src/smithy4s/codegen/ModelLoader.scala
+++ b/modules/codegen/src/smithy4s/codegen/ModelLoader.scala
@@ -22,30 +22,33 @@ import coursier.parse.RepositoryParser
 import software.amazon.smithy.build.ProjectionTransformer
 import software.amazon.smithy.build.TransformContext
 import software.amazon.smithy.model.Model
+import software.amazon.smithy.model.loader.ModelAssembler
 
 import java.io.File
 import java.net.URL
 import java.net.URLClassLoader
 
 object ModelLoader {
-  private val requiredDeps =
-    s"${smithy4s.codegen.BuildInfo.organization}:${smithy4s.codegen.BuildInfo.protocolArtifact}:${smithy4s.codegen.BuildInfo.version}" ::
-      s"${smithy4s.codegen.BuildInfo.smithyOrg}:${smithy4s.codegen.BuildInfo.smithyArtifact}:${smithy4s.codegen.BuildInfo.smithyVersion}" ::
-      Nil
 
   def load(
       specs: Set[File],
       dependencies: List[String],
       repositories: List[String],
-      transformers: List[String]
+      transformers: List[String],
+      discoverModels: Boolean
   ): (ClassLoader, Model) = {
-    val allDeps = dependencies ++ requiredDeps
+    val allDeps = dependencies
     val maybeDeps = resolveDependencies(allDeps, repositories)
     val currentClassLoader = this.getClass().getClassLoader()
 
     // Loads a model using whatever's on the current classpath (in particular, anything that
     // might be provided by smithy4s itself out of the box)
-    val modelBuilder = Model.builder()
+    val modelBuilder = Model
+      .assembler()
+      .addClasspathModels(currentClassLoader, discoverModels)
+      .assemble()
+      .unwrap()
+      .toBuilder()
 
     maybeDeps.foreach { deps =>
       // Loading the model just from upstream dependencies, in isolation
@@ -69,7 +72,9 @@ object ModelLoader {
     }
 
     val modelAssembler =
-      Model.assembler(validatorClassLoader).addModel(modelBuilder.build())
+      Model
+        .assembler(validatorClassLoader)
+        .addModel(modelBuilder.build())
 
     specs.map(_.toPath()).foreach {
       modelAssembler.addImport
@@ -127,4 +132,24 @@ object ModelLoader {
     else None
   }
 
+  implicit class ModelAssemblerOps(assembler: ModelAssembler) {
+    def addImports(urls: List[java.net.URL]): ModelAssembler = {
+      urls.foreach(assembler.addImport)
+      assembler
+    }
+
+    def addClasspathModels(
+        classLoader: ClassLoader,
+        flag: Boolean
+    ): ModelAssembler = {
+      val smithy4sResources = List(
+        "META-INF/smithy/smithy4s.smithy",
+        "META-INF/smithy/smithy4s.meta.smithy"
+      ).map(classLoader.getResource)
+
+      if (flag) assembler.discoverModels(classLoader)
+      else addImports(smithy4sResources)
+    }
+  }
+
 }