diff --git a/src/__tests__/unit/main.test.ts b/src/__tests__/unit/main.test.ts
index 36e6cb58..49bf4530 100644
--- a/src/__tests__/unit/main.test.ts
+++ b/src/__tests__/unit/main.test.ts
@@ -54,6 +54,28 @@ describe("getMetaData", () => {
     expect(result.feedbackMechanism).toContain("/issues");
   });
 
+  it("preserves existing languages over GitHub-detected languages", async () => {
+    const deps = createMockDeps();
+    const helpers = createHelpers(deps);
+
+    const existing = {
+      ...validCodeJSON,
+      languages: ["TypeScript", "Markdown"],
+    } as any;
+    const result = await getMetaData(helpers, deps, existing);
+
+    expect(result.languages).toEqual(["TypeScript", "Markdown"]);
+  });
+
+  it("falls back to GitHub-detected languages when none exist", async () => {
+    const deps = createMockDeps();
+    const helpers = createHelpers(deps);
+
+    const result = await getMetaData(helpers, deps, null);
+
+    expect(result.languages).toEqual(["TypeScript", "JavaScript"]);
+  });
+
   it("sets Archival status when isArchived", async () => {
     const deps = createMockDeps({ isArchived: true });
     const helpers = createHelpers(deps);
diff --git a/src/main.ts b/src/main.ts
index 984e2b4a..c453bb3a 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -114,6 +114,13 @@ async function getMetaData(
     ? partialCodeJSON.description
     : existingCodeJSON?.description || "";
 
+  // preserve manually curated languages when they already exist in code.json,
+  // and only fall back to GitHub detected languages for new repositories.
+  const languages =
+    existingCodeJSON?.languages && existingCodeJSON.languages.length > 0
+      ? existingCodeJSON.languages
+      : partialCodeJSON.languages;
+
   // preserve existing tags and append repository topics, de-duped
   const tags = helpers.mergeTags(
     partialCodeJSON.tags ?? [],
@@ -156,7 +163,7 @@ async function getMetaData(
     repositoryURL: partialCodeJSON.repositoryURL,
     repositoryVisibility: partialCodeJSON.repositoryVisibility,
     laborHours: partialCodeJSON.laborHours,
-    languages: partialCodeJSON.languages,
+    languages: languages,
     reuseFrequency: {
       forks: partialCodeJSON.reuseFrequency?.forks ?? 0,
       clones: existingCodeJSON?.reuseFrequency?.clones ?? 0,