diff --git a/apps/docs-generator/src/UserDocCategoryBuilder.ts b/apps/docs-generator/src/UserDocCategoryBuilder.ts
new file mode 100644
index 000000000..3eab32628
--- /dev/null
+++ b/apps/docs-generator/src/UserDocCategoryBuilder.ts
@@ -0,0 +1,70 @@
+// SPDX-FileCopyrightText: 2024 Friedrich-Alexander-Universitat Erlangen-Nurnberg
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import fs from 'node:fs';
+import path from 'node:path';
+
+export class UserDocCategoryBuilder {
+  generateDocsCategory(
+    rootPath: string,
+    dirName: string,
+    label: string,
+    position: number,
+    description: string,
+  ): string {
+    const categoryPath = path.join(rootPath, dirName);
+
+    fs.mkdirSync(categoryPath, { recursive: true });
+
+    fs.writeFileSync(
+      path.join(categoryPath, '_category_.json'),
+      this.getCategoryJSONString(label, position, description),
+    );
+
+    fs.writeFileSync(
+      path.join(categoryPath, '_category_.json.license'),
+      this.getCategoryLicenseString(new Date().getFullYear()),
+    );
+
+    fs.writeFileSync(
+      path.join(categoryPath, '.gitignore'),
+      this.getCategoryGitignoreString(new Date().getFullYear()),
+    );
+
+    return categoryPath;
+  }
+
+  private getCategoryJSONString(
+    label: string,
+    position: number,
+    description: string,
+  ): string {
+    return `{
+  "label": "${label}",
+  "position": ${position},
+  "link": {
+    "type": "generated-index",
+    "description": "${description}"
+  }
+}`;
+  }
+
+  private getCategoryLicenseString(year: number): string {
+    // REUSE-IgnoreStart
+    return `SPDX-FileCopyrightText: ${year} Friedrich-Alexander-Universitat Erlangen-Nurnberg
+
+SPDX-License-Identifier: AGPL-3.0-only`;
+    // REUSE-IgnoreEnd
+  }
+
+  private getCategoryGitignoreString(year: number): string {
+    // REUSE-IgnoreStart
+    return `# SPDX-FileCopyrightText: ${year} Friedrich-Alexander-Universitat Erlangen-Nurnberg
+#
+# SPDX-License-Identifier: AGPL-3.0-only
+
+*.md`;
+    // REUSE-IgnoreEnd
+  }
+}
diff --git a/apps/docs-generator/src/UserDocMarkdownBuilder.ts b/apps/docs-generator/src/UserDocMarkdownBuilder.ts
new file mode 100644
index 000000000..f6c8d5416
--- /dev/null
+++ b/apps/docs-generator/src/UserDocMarkdownBuilder.ts
@@ -0,0 +1,107 @@
+// SPDX-FileCopyrightText: 2024 Friedrich-Alexander-Universitat Erlangen-Nurnberg
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import {
+  type ExampleDoc,
+  type IOType,
+  MarkdownBuilder,
+  type PropertySpecification,
+} from '@jvalue/jayvee-language-server';
+
+export class UserDocMarkdownBuilder {
+  private markdownBuilder = new MarkdownBuilder();
+
+  docTitle(blockType: string): UserDocMarkdownBuilder {
+    this.markdownBuilder
+      .line('---')
+      .line(`title: ${blockType}`)
+      .line('---')
+      .newLine();
+    return this;
+  }
+
+  generationComment(): UserDocMarkdownBuilder {
+    this.markdownBuilder
+      .comment(
+        'Do NOT change this document as it is auto-generated from the language server',
+      )
+      .newLine();
+    return this;
+  }
+
+  heading(heading: string, depth = 1): UserDocMarkdownBuilder {
+    this.markdownBuilder.heading(heading, depth);
+    return this;
+  }
+
+  propertyHeading(propertyName: string, depth = 1): UserDocMarkdownBuilder {
+    this.markdownBuilder.heading(`\`${propertyName}\``, depth);
+    return this;
+  }
+
+  propertySpec(propertySpec: PropertySpecification): UserDocMarkdownBuilder {
+    this.markdownBuilder.line(`Type \`${propertySpec.type.getName()}\``);
+    if (propertySpec.defaultValue !== undefined) {
+      this.markdownBuilder
+        .newLine()
+        .line(`Default: \`${JSON.stringify(propertySpec.defaultValue)}\``);
+    }
+    this.markdownBuilder.newLine();
+    return this;
+  }
+
+  ioTypes(inputType: IOType, outputType: IOType): UserDocMarkdownBuilder {
+    this.markdownBuilder
+      .line(`Input type: \`${inputType}\``)
+      .newLine()
+      .line(`Output type: \`${outputType}\``)
+      .newLine();
+    return this;
+  }
+
+  compatibleValueType(type: string): UserDocMarkdownBuilder {
+    this.markdownBuilder.line(`Compatible value type: ${type}`);
+    this.markdownBuilder.newLine();
+    return this;
+  }
+
+  description(text?: string, depth = 2): UserDocMarkdownBuilder {
+    if (text === undefined) {
+      return this;
+    }
+    this.markdownBuilder.heading('Description', depth).line(text).newLine();
+    return this;
+  }
+
+  propertiesHeading(): UserDocMarkdownBuilder {
+    this.markdownBuilder.heading('Properties', 2);
+    return this;
+  }
+
+  validation(text?: string, depth = 2): UserDocMarkdownBuilder {
+    if (text === undefined) {
+      return this;
+    }
+    this.markdownBuilder.heading('Validation', depth).line(text).newLine();
+    return this;
+  }
+
+  examples(examples?: ExampleDoc[], depth = 2): UserDocMarkdownBuilder {
+    if (examples === undefined) {
+      return this;
+    }
+    for (const [index, example] of examples.entries()) {
+      this.markdownBuilder
+        .heading(`Example ${index + 1}`, depth)
+        .code(example.code, 'jayvee')
+        .line(example.description)
+        .newLine();
+    }
+    return this;
+  }
+
+  build(): string {
+    return this.markdownBuilder.build();
+  }
+}
diff --git a/apps/docs-generator/src/main.ts b/apps/docs-generator/src/main.ts
index a0a35cd68..59bad8aa2 100644
--- a/apps/docs-generator/src/main.ts
+++ b/apps/docs-generator/src/main.ts
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: 2023 Friedrich-Alexander-Universitat Erlangen-Nurnberg
+// SPDX-FileCopyrightText: 2024 Friedrich-Alexander-Universitat Erlangen-Nurnberg
 //
 // SPDX-License-Identifier: AGPL-3.0-only
 
@@ -9,13 +9,15 @@ import { fileURLToPath } from 'node:url';
 import {
   type JayveeServices,
   createJayveeServices,
-  getAllBuiltinBlockTypes,
   getAllBuiltinConstraintTypes,
+  getAllReferenceableBlockTypes,
   initializeWorkspace,
 } from '@jvalue/jayvee-language-server';
 import { NodeFileSystem } from 'langium/node';
 
 import { UserDocGenerator } from './user-doc-generator';
+import { getBlockTypeDomain } from './util';
+import { UserDocCategoryBuilder } from './UserDocCategoryBuilder';
 
 /** ESM does not know __filename and __dirname, so defined here */
 const __filename = fileURLToPath(import.meta.url);
@@ -38,21 +40,49 @@ function generateBlockTypeDocs(
   services: JayveeServices,
   docsAppPath: string,
 ): void {
-  const blockTypes = getAllBuiltinBlockTypes(
+  const blockTypes = getAllReferenceableBlockTypes(
     services.shared.workspace.LangiumDocuments,
     services.WrapperFactories,
   );
-
   const docsPath = join(docsAppPath, 'docs', 'user', 'block-types');
 
+  const domainsGenerated: string[] = [];
+
+  const userCategoryBuilder = new UserDocCategoryBuilder();
+  userCategoryBuilder.generateDocsCategory(
+    docsPath,
+    'builtin',
+    'Built-in Blocks',
+    0,
+    `Built-in Blocks.`,
+  );
+
   for (const blockType of blockTypes) {
+    const blockDomain = getBlockTypeDomain(blockType);
+    if (blockDomain !== undefined) {
+      if (!domainsGenerated.includes(blockDomain)) {
+        const userCategoryBuilder = new UserDocCategoryBuilder();
+        userCategoryBuilder.generateDocsCategory(
+          docsPath,
+          blockDomain,
+          `Domain extension: ${blockDomain}`,
+          domainsGenerated.length + 1,
+          `Blocks from the ${blockDomain} domain extension.`,
+        );
+        domainsGenerated.push(blockDomain);
+      }
+    }
     const userDocBuilder = new UserDocGenerator(services);
     const blockTypeDoc = userDocBuilder.generateBlockTypeDoc(blockType);
 
     const fileName = `${blockType.type}.md`;
-    writeFileSync(join(docsPath, fileName), blockTypeDoc, {
-      flag: 'w',
-    });
+    writeFileSync(
+      join(docsPath, blockDomain ?? 'builtin', fileName),
+      blockTypeDoc,
+      {
+        flag: 'w',
+      },
+    );
     console.info(`Generated file ${fileName}`);
   }
 }
diff --git a/apps/docs-generator/src/user-doc-generator.ts b/apps/docs-generator/src/user-doc-generator.ts
index 771aa31dd..50fb9a4e3 100644
--- a/apps/docs-generator/src/user-doc-generator.ts
+++ b/apps/docs-generator/src/user-doc-generator.ts
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: 2023 Friedrich-Alexander-Universitat Erlangen-Nurnberg
+// SPDX-FileCopyrightText: 2024 Friedrich-Alexander-Universitat Erlangen-Nurnberg
 //
 // SPDX-License-Identifier: AGPL-3.0-only
 
@@ -9,16 +9,15 @@ import {
   type BlockTypeWrapper,
   type ConstraintTypeWrapper,
   type ExampleDoc,
-  type IOType,
   type JayveeBlockTypeDocGenerator,
   type JayveeConstraintTypeDocGenerator,
   type JayveeServices,
   type JayveeValueTypesDocGenerator,
-  MarkdownBuilder,
   type PrimitiveValueType,
-  type PropertySpecification,
 } from '@jvalue/jayvee-language-server';
 
+import { UserDocMarkdownBuilder } from './UserDocMarkdownBuilder';
+
 export class UserDocGenerator
   implements
     JayveeBlockTypeDocGenerator,
@@ -45,7 +44,7 @@ that fullfil [_constraints_](./primitive-value-types#constraints).`.trim(),
       .filter((valueType) => valueType.isReferenceableByUser())
       .forEach((valueType) => {
         assert(
-          valueType.getUserDoc(),
+          valueType.getUserDoc() !== undefined,
           `Documentation is missing for user extendable value type: ${valueType.getName()}`,
         );
         builder
@@ -181,100 +180,3 @@ block ExampleTableInterpreter oftype TableInterpreter {
     };
   }
 }
-
-class UserDocMarkdownBuilder {
-  private markdownBuilder = new MarkdownBuilder();
-
-  docTitle(blockType: string): UserDocMarkdownBuilder {
-    this.markdownBuilder
-      .line('---')
-      .line(`title: ${blockType}`)
-      .line('---')
-      .newLine();
-    return this;
-  }
-
-  generationComment(): UserDocMarkdownBuilder {
-    this.markdownBuilder
-      .comment(
-        'Do NOT change this document as it is auto-generated from the language server',
-      )
-      .newLine();
-    return this;
-  }
-
-  heading(heading: string, depth = 1): UserDocMarkdownBuilder {
-    this.markdownBuilder.heading(heading, depth);
-    return this;
-  }
-
-  propertyHeading(propertyName: string, depth = 1): UserDocMarkdownBuilder {
-    this.markdownBuilder.heading(`\`${propertyName}\``, depth);
-    return this;
-  }
-
-  propertySpec(propertySpec: PropertySpecification): UserDocMarkdownBuilder {
-    this.markdownBuilder.line(`Type \`${propertySpec.type.getName()}\``);
-    if (propertySpec.defaultValue !== undefined) {
-      this.markdownBuilder
-        .newLine()
-        .line(`Default: \`${JSON.stringify(propertySpec.defaultValue)}\``);
-    }
-    this.markdownBuilder.newLine();
-    return this;
-  }
-
-  ioTypes(inputType: IOType, outputType: IOType): UserDocMarkdownBuilder {
-    this.markdownBuilder
-      .line(`Input type: \`${inputType}\``)
-      .newLine()
-      .line(`Output type: \`${outputType}\``)
-      .newLine();
-    return this;
-  }
-
-  compatibleValueType(type: string): UserDocMarkdownBuilder {
-    this.markdownBuilder.line(`Compatible value type: ${type}`);
-    this.markdownBuilder.newLine();
-    return this;
-  }
-
-  description(text?: string, depth = 2): UserDocMarkdownBuilder {
-    if (text === undefined) {
-      return this;
-    }
-    this.markdownBuilder.heading('Description', depth).line(text).newLine();
-    return this;
-  }
-
-  propertiesHeading(): UserDocMarkdownBuilder {
-    this.markdownBuilder.heading('Properties', 2);
-    return this;
-  }
-
-  validation(text?: string, depth = 2): UserDocMarkdownBuilder {
-    if (text === undefined) {
-      return this;
-    }
-    this.markdownBuilder.heading('Validation', depth).line(text).newLine();
-    return this;
-  }
-
-  examples(examples?: ExampleDoc[], depth = 2): UserDocMarkdownBuilder {
-    if (examples === undefined) {
-      return this;
-    }
-    for (const [index, example] of examples.entries()) {
-      this.markdownBuilder
-        .heading(`Example ${index + 1}`, depth)
-        .code(example.code, 'jayvee')
-        .line(example.description)
-        .newLine();
-    }
-    return this;
-  }
-
-  build(): string {
-    return this.markdownBuilder.build();
-  }
-}
diff --git a/apps/docs-generator/src/util.ts b/apps/docs-generator/src/util.ts
new file mode 100644
index 000000000..505f3e0b2
--- /dev/null
+++ b/apps/docs-generator/src/util.ts
@@ -0,0 +1,28 @@
+// SPDX-FileCopyrightText: 2024 Friedrich-Alexander-Universitat Erlangen-Nurnberg
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import path from 'node:path';
+
+import { type BlockTypeWrapper } from '@jvalue/jayvee-language-server';
+
+/**
+ * Returns the domain of a block type or undefined if it does not come from a domain extension in the stdlib.
+ */
+export function getBlockTypeDomain(
+  blockType: BlockTypeWrapper,
+): string | undefined {
+  const filePath = blockType.astNode.$container?.$document?.uri.path;
+
+  if (filePath === undefined) {
+    return undefined;
+  }
+
+  const pathElements = filePath.split(path.sep);
+
+  // pathElements[0] is an empty string since the path starts with /
+  // pathElements[1] is the stdlib directory
+  if (pathElements[2] === 'domain') {
+    return pathElements[3] ?? undefined;
+  }
+}
diff --git a/apps/docs/docs/user/block-types/.gitignore b/apps/docs/docs/user/block-types/.gitignore
index 277e9bb17..85fd9530f 100644
--- a/apps/docs/docs/user/block-types/.gitignore
+++ b/apps/docs/docs/user/block-types/.gitignore
@@ -2,4 +2,5 @@
 #
 # SPDX-License-Identifier: AGPL-3.0-only
 
-*.md
\ No newline at end of file
+*.md
+*/*
\ No newline at end of file
diff --git a/apps/docs/docs/user/composite-block-types.md b/apps/docs/docs/user/composite-block-types.md
index e0e9df159..dcf526a66 100644
--- a/apps/docs/docs/user/composite-block-types.md
+++ b/apps/docs/docs/user/composite-block-types.md
@@ -1,5 +1,5 @@
 ---
-sidebar_position: 4
+sidebar_position: 7
 ---
 
 # Composite Block Types
diff --git a/apps/docs/docs/user/expressions.md b/apps/docs/docs/user/expressions.md
index a2cceb49c..5fa547f6a 100644
--- a/apps/docs/docs/user/expressions.md
+++ b/apps/docs/docs/user/expressions.md
@@ -1,5 +1,5 @@
 ---
-sidebar_position: 7
+sidebar_position: 8
 ---
 
 # Expressions
diff --git a/apps/docs/docs/user/transforms.md b/apps/docs/docs/user/transforms.md
index 468a22cb9..002b6303d 100644
--- a/apps/docs/docs/user/transforms.md
+++ b/apps/docs/docs/user/transforms.md
@@ -74,4 +74,4 @@ transform StatusToBoolean {
 ## Applying transforms to table columns
 
 Transforms can be applied to columns of a table.
-Please refer to the documentation of the [`TableTransformer` block type](./block-types/TableTransformer.md) to find out how.
+Please refer to the documentation of the [`TableTransformer` block type](./block-types/builtin/TableTransformer.md) to find out how.
diff --git a/libs/interpreter-lib/src/std-extension.spec.ts b/libs/interpreter-lib/src/std-extension.spec.ts
index aa30d9654..1e3bba282 100644
--- a/libs/interpreter-lib/src/std-extension.spec.ts
+++ b/libs/interpreter-lib/src/std-extension.spec.ts
@@ -9,17 +9,19 @@ import { StdExecExtension } from '@jvalue/jayvee-extensions/std/exec';
 import {
   type BlockTypeWrapper,
   createJayveeServices,
-  getAllBuiltinBlockTypes,
+  getAllReferenceableBlockTypes,
   initializeWorkspace,
+  isBuiltinBlockTypeDefinition,
 } from '@jvalue/jayvee-language-server';
 import { NodeFileSystem } from 'langium/node';
 
 async function loadAllBuiltinBlockTypes(): Promise<BlockTypeWrapper[]> {
   const services = createJayveeServices(NodeFileSystem).Jayvee;
   await initializeWorkspace(services);
-  return getAllBuiltinBlockTypes(
+  return getAllReferenceableBlockTypes(
     services.shared.workspace.LangiumDocuments,
     services.WrapperFactories,
+    (blockType) => isBuiltinBlockTypeDefinition(blockType),
   );
 }
 
diff --git a/libs/language-server/src/lib/ast/model-util.ts b/libs/language-server/src/lib/ast/model-util.ts
index d243423b9..755481ed8 100644
--- a/libs/language-server/src/lib/ast/model-util.ts
+++ b/libs/language-server/src/lib/ast/model-util.ts
@@ -8,17 +8,17 @@ import { strict as assert } from 'assert';
 import { type AstNode, AstUtils, type LangiumDocuments } from 'langium';
 
 import {
-  type BuiltinBlockTypeDefinition,
   type BuiltinConstrainttypeDefinition,
   type ExportDefinition,
   type ExportableElement,
   type JayveeModel,
-  isBuiltinBlockTypeDefinition,
+  type ReferenceableBlockTypeDefinition,
   isBuiltinConstrainttypeDefinition,
   isExportDefinition,
   isExportableElement,
   isExportableElementDefinition,
   isJayveeModel,
+  isReferenceableBlockTypeDefinition,
 } from './generated/ast';
 import {
   type BlockTypeWrapper,
@@ -51,17 +51,20 @@ export function getNextAstNodeContainer<T extends AstNode>(
 }
 
 /**
- * Utility function that gets all builtin block types.
+ * Utility function that gets all referenceable block types, optionally filtered by a provided filter function.
  * Duplicates are only added once.
  * Make sure to call {@link initializeWorkspace} first so that the file system is initialized.
  */
-export function getAllBuiltinBlockTypes(
+export function getAllReferenceableBlockTypes(
   documentService: LangiumDocuments,
   wrapperFactories: WrapperFactoryProvider,
+  filter: (
+    blockTypeDefinition: ReferenceableBlockTypeDefinition,
+  ) => boolean = () => true,
 ): BlockTypeWrapper[] {
-  const allBuiltinBlockTypes: BlockTypeWrapper[] = [];
-  const visitedBuiltinBlockTypeDefinitions =
-    new Set<BuiltinBlockTypeDefinition>();
+  const allBlockTypes: BlockTypeWrapper[] = [];
+  const visitedBlockTypeDefinitions =
+    new Set<ReferenceableBlockTypeDefinition>();
 
   documentService.all
     .map((document) => document.parseResult.value)
@@ -69,25 +72,27 @@ export function getAllBuiltinBlockTypes(
       if (!isJayveeModel(parsedDocument)) {
         throw new Error('Expected parsed document to be a JayveeModel');
       }
-      const allBlockTypes = AstUtils.streamAllContents(parsedDocument).filter(
-        isBuiltinBlockTypeDefinition,
-      );
-      allBlockTypes.forEach((blockTypeDefinition) => {
+      const allReferenceableBlockTypes = AstUtils.streamAllContents(
+        parsedDocument,
+      )
+        .filter(isReferenceableBlockTypeDefinition)
+        .filter(filter);
+      allReferenceableBlockTypes.forEach((blockTypeDefinition) => {
         const wasAlreadyVisited =
-          visitedBuiltinBlockTypeDefinitions.has(blockTypeDefinition);
+          visitedBlockTypeDefinitions.has(blockTypeDefinition);
         if (wasAlreadyVisited) {
           return;
         }
 
         if (wrapperFactories.BlockType.canWrap(blockTypeDefinition)) {
-          allBuiltinBlockTypes.push(
+          allBlockTypes.push(
             wrapperFactories.BlockType.wrap(blockTypeDefinition),
           );
-          visitedBuiltinBlockTypeDefinitions.add(blockTypeDefinition);
+          visitedBlockTypeDefinitions.add(blockTypeDefinition);
         }
       });
     });
-  return allBuiltinBlockTypes;
+  return allBlockTypes;
 }
 
 /**
diff --git a/libs/language-server/src/lib/lsp/jayvee-completion-provider.ts b/libs/language-server/src/lib/lsp/jayvee-completion-provider.ts
index 7264c26c0..afaa7a71c 100644
--- a/libs/language-server/src/lib/lsp/jayvee-completion-provider.ts
+++ b/libs/language-server/src/lib/lsp/jayvee-completion-provider.ts
@@ -39,8 +39,8 @@ import {
   isValuetypeDefinition,
 } from '../ast/generated/ast';
 import {
-  getAllBuiltinBlockTypes,
   getAllBuiltinConstraintTypes,
+  getAllReferenceableBlockTypes,
   getExportedElements,
 } from '../ast/model-util';
 import { LspDocGenerator } from '../docs/lsp-doc-generator';
@@ -112,7 +112,7 @@ export class JayveeCompletionProvider extends DefaultCompletionProvider {
     context: CompletionContext,
     acceptor: CompletionAcceptor,
   ): MaybePromise<void> {
-    const blockTypes = getAllBuiltinBlockTypes(
+    const blockTypes = getAllReferenceableBlockTypes(
       this.langiumDocuments,
       this.wrapperFactories,
     );