diff --git a/extensions/ql-vscode/src/data-extensions-editor/data-extensions-editor-view.ts b/extensions/ql-vscode/src/data-extensions-editor/data-extensions-editor-view.ts
index f1835c9efda..24d08e76975 100644
--- a/extensions/ql-vscode/src/data-extensions-editor/data-extensions-editor-view.ts
+++ b/extensions/ql-vscode/src/data-extensions-editor/data-extensions-editor-view.ts
@@ -148,7 +148,11 @@ export class DataExtensionsEditorView extends AbstractWebview<
     externalApiUsages: ExternalApiUsage[],
     modeledMethods: Record<string, ModeledMethod>,
   ): Promise<void> {
-    const yaml = createDataExtensionYaml(externalApiUsages, modeledMethods);
+    const yaml = createDataExtensionYaml(
+      this.databaseItem.language,
+      externalApiUsages,
+      modeledMethods,
+    );
 
     await outputFile(this.modelFilename, yaml);
 
diff --git a/extensions/ql-vscode/src/data-extensions-editor/extension-pack-picker.ts b/extensions/ql-vscode/src/data-extensions-editor/extension-pack-picker.ts
index df47932a45a..87f2d722030 100644
--- a/extensions/ql-vscode/src/data-extensions-editor/extension-pack-picker.ts
+++ b/extensions/ql-vscode/src/data-extensions-editor/extension-pack-picker.ts
@@ -23,7 +23,7 @@ const packNameLength = 128;
 
 export async function pickExtensionPackModelFile(
   cliServer: Pick<CodeQLCliServer, "resolveQlpacks" | "resolveExtensions">,
-  databaseItem: Pick<DatabaseItem, "name">,
+  databaseItem: Pick<DatabaseItem, "name" | "language">,
   progress: ProgressCallback,
   token: CancellationToken,
 ): Promise<string | undefined> {
@@ -53,7 +53,7 @@ export async function pickExtensionPackModelFile(
 
 async function pickExtensionPack(
   cliServer: Pick<CodeQLCliServer, "resolveQlpacks">,
-  databaseItem: Pick<DatabaseItem, "name">,
+  databaseItem: Pick<DatabaseItem, "name" | "language">,
   progress: ProgressCallback,
   token: CancellationToken,
 ): Promise<string | undefined> {
@@ -184,7 +184,7 @@ async function pickModelFile(
 }
 
 async function pickNewExtensionPack(
-  databaseItem: Pick<DatabaseItem, "name">,
+  databaseItem: Pick<DatabaseItem, "name" | "language">,
   token: CancellationToken,
 ): Promise<string | undefined> {
   const workspaceFolders = getOnDiskWorkspaceFoldersObjects();
@@ -257,7 +257,7 @@ async function pickNewExtensionPack(
       version: "0.0.0",
       library: true,
       extensionTargets: {
-        "codeql/java-all": "*",
+        [`codeql/${databaseItem.language}-all`]: "*",
       },
       dataExtensions: ["models/**/*.yml"],
     }),
diff --git a/extensions/ql-vscode/src/data-extensions-editor/yaml.ts b/extensions/ql-vscode/src/data-extensions-editor/yaml.ts
index 9cd869543c6..9032727487f 100644
--- a/extensions/ql-vscode/src/data-extensions-editor/yaml.ts
+++ b/extensions/ql-vscode/src/data-extensions-editor/yaml.ts
@@ -43,6 +43,7 @@ function createDataProperty(
 }
 
 export function createDataExtensionYaml(
+  language: string,
   externalApiUsages: ExternalApiUsage[],
   modeledMethods: Record<string, ModeledMethod>,
 ) {
@@ -69,7 +70,7 @@ export function createDataExtensionYaml(
 
   const extensions = Object.entries(extensiblePredicateDefinitions).map(
     ([type, definition]) => `  - addsTo:
-      pack: codeql/java-all
+      pack: codeql/${language}-all
       extensible: ${definition.extensiblePredicate}
     data:${createDataProperty(
       methodsByType[type as Exclude<ModeledMethodType, "none">],
diff --git a/extensions/ql-vscode/test/unit-tests/data-extensions-editor/yaml.test.ts b/extensions/ql-vscode/test/unit-tests/data-extensions-editor/yaml.test.ts
index dde07e6a43f..a499e12ebd5 100644
--- a/extensions/ql-vscode/test/unit-tests/data-extensions-editor/yaml.test.ts
+++ b/extensions/ql-vscode/test/unit-tests/data-extensions-editor/yaml.test.ts
@@ -6,6 +6,7 @@ import {
 describe("createDataExtensionYaml", () => {
   it("creates the correct YAML file", () => {
     const yaml = createDataExtensionYaml(
+      "java",
       [
         {
           signature: "org.sql2o.Connection#createQuery(String)",
@@ -99,6 +100,32 @@ describe("createDataExtensionYaml", () => {
       pack: codeql/java-all
       extensible: neutralModel
     data: []
+`);
+  });
+
+  it("includes the correct language", () => {
+    const yaml = createDataExtensionYaml("csharp", [], {});
+
+    expect(yaml).toEqual(`extensions:
+  - addsTo:
+      pack: codeql/csharp-all
+      extensible: sourceModel
+    data: []
+
+  - addsTo:
+      pack: codeql/csharp-all
+      extensible: sinkModel
+    data: []
+
+  - addsTo:
+      pack: codeql/csharp-all
+      extensible: summaryModel
+    data: []
+
+  - addsTo:
+      pack: codeql/csharp-all
+      extensible: neutralModel
+    data: []
 `);
   });
 });
diff --git a/extensions/ql-vscode/test/vscode-tests/no-workspace/data-extensions-editor/extension-pack-picker.test.ts b/extensions/ql-vscode/test/vscode-tests/no-workspace/data-extensions-editor/extension-pack-picker.test.ts
index 2846f6c8850..88ae01773d3 100644
--- a/extensions/ql-vscode/test/vscode-tests/no-workspace/data-extensions-editor/extension-pack-picker.test.ts
+++ b/extensions/ql-vscode/test/vscode-tests/no-workspace/data-extensions-editor/extension-pack-picker.test.ts
@@ -27,6 +27,7 @@ describe("pickExtensionPackModelFile", () => {
   };
   const databaseItem = {
     name: "github/vscode-codeql",
+    language: "java",
   };
 
   const cancellationTokenSource = new CancellationTokenSource();
@@ -304,6 +305,71 @@ describe("pickExtensionPackModelFile", () => {
     });
   });
 
+  it("allows user to create an extension pack when there are no extension packs with a different language", async () => {
+    const cliServer = mockCliServer({}, { models: [], data: {} });
+
+    const tmpDir = await dir({
+      unsafeCleanup: true,
+    });
+
+    showQuickPickSpy.mockResolvedValueOnce({
+      label: "codeql-custom-queries-java",
+      path: tmpDir.path,
+    } as QuickPickItem);
+    showInputBoxSpy.mockResolvedValueOnce("my-extension-pack");
+    showInputBoxSpy.mockResolvedValue("models/my-model.yml");
+
+    expect(
+      await pickExtensionPackModelFile(
+        cliServer,
+        {
+          ...databaseItem,
+          language: "csharp",
+        },
+        progress,
+        token,
+      ),
+    ).toEqual(join(tmpDir.path, "my-extension-pack", "models", "my-model.yml"));
+    expect(showQuickPickSpy).toHaveBeenCalledTimes(1);
+    expect(showInputBoxSpy).toHaveBeenCalledTimes(2);
+    expect(showInputBoxSpy).toHaveBeenCalledWith(
+      {
+        title: expect.stringMatching(/extension pack/i),
+        prompt: expect.stringMatching(/extension pack/i),
+        placeHolder: expect.stringMatching(/github\/vscode-codeql-extensions/),
+        validateInput: expect.any(Function),
+      },
+      token,
+    );
+    expect(showInputBoxSpy).toHaveBeenCalledWith(
+      {
+        title: expect.stringMatching(/model file/),
+        value: "models/github.vscode-codeql.model.yml",
+        validateInput: expect.any(Function),
+      },
+      token,
+    );
+    expect(cliServer.resolveQlpacks).toHaveBeenCalled();
+    expect(cliServer.resolveExtensions).toHaveBeenCalled();
+
+    expect(
+      loadYaml(
+        await readFile(
+          join(tmpDir.path, "my-extension-pack", "codeql-pack.yml"),
+          "utf8",
+        ),
+      ),
+    ).toEqual({
+      name: "my-extension-pack",
+      version: "0.0.0",
+      library: true,
+      extensionTargets: {
+        "codeql/csharp-all": "*",
+      },
+      dataExtensions: ["models/**/*.yml"],
+    });
+  });
+
   it("allows cancelling the workspace folder selection", async () => {
     const cliServer = mockCliServer({}, { models: [], data: {} });