diff --git a/api/routers/specs.py b/api/routers/specs.py
index 874e670297..7574033410 100644
--- a/api/routers/specs.py
+++ b/api/routers/specs.py
@@ -117,14 +117,14 @@ async def _build_spec_detail(db: AsyncSession, spec_id: str) -> SpecDetailRespon
     )
 
 
-async def _build_impl_code(db: AsyncSession, spec_id: str, library: str) -> dict:
+async def _build_impl_code(db: AsyncSession, spec_id: str, library: str, language: str = "python") -> dict:
     repo = ImplRepository(db)
-    impl = await repo.get_code(spec_id, library)
+    impl = await repo.get_code(spec_id, library, language)
 
     if not impl or not impl.code:
-        raise_not_found("Implementation code", f"{spec_id}/{library}")
+        raise_not_found("Implementation code", f"{spec_id}/{language}/{library}")
 
-    return {"spec_id": spec_id, "library": library, "code": strip_noqa_comments(impl.code)}
+    return {"spec_id": spec_id, "library": library, "language": language, "code": strip_noqa_comments(impl.code)}
 
 
 async def _build_spec_images(db: AsyncSession, spec_id: str) -> dict:
@@ -196,18 +196,25 @@ async def _refresh() -> SpecDetailResponse:
 
 
 @router.get("/specs/{spec_id}/{library}/code")
-async def get_impl_code(spec_id: str, library: str, db: AsyncSession = Depends(require_db)):
-    """Get implementation code for a specific spec + library (code field deferred in main query)."""
+async def get_impl_code(spec_id: str, library: str, language: str = "python", db: AsyncSession = Depends(require_db)):
+    """Get implementation code for a specific spec + library + language.
+
+    Code field is deferred in the main `/specs/{id}` query so it must be
+    fetched here on-demand. `language` disambiguates when the same library_id
+    could exist for multiple languages (today only ggplot2 is R; everything
+    else is Python). Defaults to python for backwards compat with older
+    clients that don't send the param.
+    """
 
     async def _fetch() -> dict:
-        return await _build_impl_code(db, spec_id, library)
+        return await _build_impl_code(db, spec_id, library, language)
 
     async def _refresh() -> dict:
         async with get_db_context() as fresh_db:
-            return await _build_impl_code(fresh_db, spec_id, library)
+            return await _build_impl_code(fresh_db, spec_id, library, language)
 
     return await get_or_set_cache(
-        cache_key("impl_code", spec_id, library),
+        cache_key("impl_code", spec_id, language, library),
         _fetch,
         refresh_after=settings.cache_refresh_after,
         refresh_factory=_refresh,
diff --git a/api/routers/stats.py b/api/routers/stats.py
index 63eb20538c..278faecc85 100644
--- a/api/routers/stats.py
+++ b/api/routers/stats.py
@@ -7,7 +7,7 @@
 from api.dependencies import optional_db
 from api.schemas import StatsResponse
 from core.config import settings
-from core.constants import LIBRARIES_METADATA
+from core.constants import LANGUAGES_METADATA, LIBRARIES_METADATA
 from core.database import ImplRepository, LibraryRepository, SpecRepository
 from core.database.connection import get_db_context
 
@@ -27,8 +27,13 @@ async def _refresh_stats() -> StatsResponse:
 
     specs_with_impls = [s for s in specs if s.impls]
     total_impls = sum(len(s.impls) for s in specs)
+    languages = len({lib.language_id for lib in libraries}) or len(LANGUAGES_METADATA)
     return StatsResponse(
-        specs=len(specs_with_impls), plots=total_impls, libraries=len(libraries), lines_of_code=total_loc
+        specs=len(specs_with_impls),
+        plots=total_impls,
+        libraries=len(libraries),
+        languages=languages,
+        lines_of_code=total_loc,
     )
 
 
@@ -37,10 +42,10 @@ async def get_stats(db: AsyncSession | None = Depends(optional_db)):
     """
     Get platform statistics.
 
-    Returns counts of specs, implementations (plots), and libraries.
+    Returns counts of specs, implementations (plots), libraries, and languages.
     """
     if db is None:
-        return StatsResponse(specs=0, plots=0, libraries=len(LIBRARIES_METADATA))
+        return StatsResponse(specs=0, plots=0, libraries=len(LIBRARIES_METADATA), languages=len(LANGUAGES_METADATA))
 
     async def _fetch() -> StatsResponse:
         spec_repo = SpecRepository(db)
@@ -52,8 +57,13 @@ async def _fetch() -> StatsResponse:
 
         specs_with_impls = [s for s in specs if s.impls]
         total_impls = sum(len(s.impls) for s in specs)
+        languages = len({lib.language_id for lib in libraries}) or len(LANGUAGES_METADATA)
         return StatsResponse(
-            specs=len(specs_with_impls), plots=total_impls, libraries=len(libraries), lines_of_code=total_loc
+            specs=len(specs_with_impls),
+            plots=total_impls,
+            libraries=len(libraries),
+            languages=languages,
+            lines_of_code=total_loc,
         )
 
     return await get_or_set_cache(
diff --git a/api/schemas.py b/api/schemas.py
index ba64a9cb0c..674a940f8d 100644
--- a/api/schemas.py
+++ b/api/schemas.py
@@ -150,4 +150,5 @@ class StatsResponse(BaseModel):
     specs: int
     plots: int
     libraries: int
+    languages: int = 0
     lines_of_code: int = 0
diff --git a/app/src/components/NumbersStrip.tsx b/app/src/components/NumbersStrip.tsx
index 421d79b310..d9de66aa68 100644
--- a/app/src/components/NumbersStrip.tsx
+++ b/app/src/components/NumbersStrip.tsx
@@ -2,7 +2,7 @@ import Box from '@mui/material/Box';
 import { typography } from '../theme';
 
 interface NumbersStripProps {
-  stats: { specs: number; plots: number; libraries: number; lines_of_code?: number } | null;
+  stats: { specs: number; plots: number; libraries: number; languages?: number; lines_of_code?: number } | null;
 }
 
 function formatLoc(n: number | undefined): string {
@@ -13,7 +13,7 @@ function formatLoc(n: number | undefined): string {
 
 export function NumbersStrip({ stats }: NumbersStripProps) {
   const items = [
-    { value: '1', label: 'languages' },
+    { value: stats?.languages ? String(stats.languages) : '—', label: 'languages' },
     { value: stats ? String(stats.libraries) : '—', label: 'libraries' },
     { value: stats ? String(stats.specs) : '—', label: 'specifications' },
     { value: stats ? stats.plots.toLocaleString() : '—', label: 'implementations' },
diff --git a/app/src/constants/index.ts b/app/src/constants/index.ts
index 70172c00d2..8e72ef139d 100644
--- a/app/src/constants/index.ts
+++ b/app/src/constants/index.ts
@@ -6,7 +6,7 @@ export const API_URL = import.meta.env.VITE_API_URL || 'http://localhost:8000';
 // sent with fetch. Falls back to API_URL locally where there's no Worker.
 export const DEBUG_API_URL = import.meta.env.VITE_DEBUG_API_URL || API_URL;
 export const GITHUB_URL = 'https://github.com/MarkusNeusinger/anyplot';
-export const LIBRARIES = ['altair', 'bokeh', 'highcharts', 'letsplot', 'matplotlib', 'plotly', 'plotnine', 'pygal', 'seaborn'];
+export const LIBRARIES = ['altair', 'bokeh', 'ggplot2', 'highcharts', 'letsplot', 'matplotlib', 'plotly', 'plotnine', 'pygal', 'seaborn'];
 export const BATCH_SIZE = 36;
 
 // Image size: 'normal' or 'compact' (half size)
@@ -23,4 +23,5 @@ export const LIB_ABBREV: Record<string, string> = {
   pygal: 'pyg',
   highcharts: 'hc',
   letsplot: 'lp',
+  ggplot2: 'gg',
 };
diff --git a/app/src/hooks/useCodeFetch.test.ts b/app/src/hooks/useCodeFetch.test.ts
index ddaac0f54c..9c9bdc4a4b 100644
--- a/app/src/hooks/useCodeFetch.test.ts
+++ b/app/src/hooks/useCodeFetch.test.ts
@@ -159,5 +159,44 @@ describe('useCodeFetch', () => {
       expect(snsResult).toContain('seaborn');
       expect(globalThis.fetch).toHaveBeenCalledTimes(2);
     });
+
+    it('appends ?language= for non-python languages', async () => {
+      const ggCode = 'library(ggplot2)';
+      globalThis.fetch = vi.fn().mockResolvedValue({
+        ok: true,
+        json: async () => ({ code: ggCode }),
+      });
+
+      const { result } = renderHook(() => useCodeFetch());
+      let code: string | null = null;
+      await act(async () => {
+        code = await result.current.fetchCode('scatter-basic', 'ggplot2', 'r');
+      });
+
+      expect(code).toBe(ggCode);
+      expect(globalThis.fetch).toHaveBeenCalledWith(
+        expect.stringContaining('/specs/scatter-basic/ggplot2/code?language=r')
+      );
+    });
+
+    it('caches python and r impls under separate keys for the same library_id', async () => {
+      const pyCode = 'import matplotlib';
+      const rCode = 'library(matplotlib)';
+      globalThis.fetch = vi.fn()
+        .mockResolvedValueOnce({ ok: true, json: async () => ({ code: pyCode }) })
+        .mockResolvedValueOnce({ ok: true, json: async () => ({ code: rCode }) });
+
+      const { result } = renderHook(() => useCodeFetch());
+      let py: string | null = null;
+      let r: string | null = null;
+      await act(async () => {
+        py = await result.current.fetchCode('hypothetical', 'matplotlib');
+        r = await result.current.fetchCode('hypothetical', 'matplotlib', 'r');
+      });
+
+      expect(py).toBe(pyCode);
+      expect(r).toBe(rCode);
+      expect(globalThis.fetch).toHaveBeenCalledTimes(2);
+    });
   });
 });
diff --git a/app/src/hooks/useCodeFetch.ts b/app/src/hooks/useCodeFetch.ts
index cdd9bdad53..2b5e7707b5 100644
--- a/app/src/hooks/useCodeFetch.ts
+++ b/app/src/hooks/useCodeFetch.ts
@@ -9,27 +9,31 @@ import { useState, useCallback, useRef } from 'react';
 import { API_URL } from '../constants';
 
 interface CodeCache {
-  [key: string]: string | null; // key: `${spec_id}:${library}`
+  [key: string]: string | null; // key: `${spec_id}:${language}:${library}`
 }
 
 interface UseCodeFetchReturn {
-  fetchCode: (specId: string, library: string) => Promise<string | null>;
-  getCode: (specId: string, library: string) => string | null;
+  fetchCode: (specId: string, library: string, language?: string) => Promise<string | null>;
+  getCode: (specId: string, library: string, language?: string) => string | null;
   isLoading: boolean;
 }
 
+// Default language matches the API's own default so old call sites — and the
+// majority of (Python) impls — keep producing the same URL and cache key.
+const cacheKey = (specId: string, library: string, language: string) =>
+  `${specId}:${language}:${library}`;
+
 export function useCodeFetch(): UseCodeFetchReturn {
   const [isLoading, setIsLoading] = useState(false);
   const cacheRef = useRef<CodeCache>({});
   const pendingRef = useRef<Map<string, Promise<string | null>>>(new Map());
 
-  const getCode = useCallback((specId: string, library: string): string | null => {
-    const key = `${specId}:${library}`;
-    return cacheRef.current[key] ?? null;
+  const getCode = useCallback((specId: string, library: string, language: string = 'python'): string | null => {
+    return cacheRef.current[cacheKey(specId, library, language)] ?? null;
   }, []);
 
-  const fetchCode = useCallback(async (specId: string, library: string): Promise<string | null> => {
-    const key = `${specId}:${library}`;
+  const fetchCode = useCallback(async (specId: string, library: string, language: string = 'python'): Promise<string | null> => {
+    const key = cacheKey(specId, library, language);
 
     // Check cache first
     if (key in cacheRef.current) {
@@ -42,11 +46,16 @@ export function useCodeFetch(): UseCodeFetchReturn {
       return pending;
     }
 
-    // Fetch from lightweight code endpoint
+    // Only append the language query param when it diverges from the API
+    // default — keeps URLs for the common Python case unchanged.
+    const url = language === 'python'
+      ? `${API_URL}/specs/${specId}/${library}/code`
+      : `${API_URL}/specs/${specId}/${library}/code?language=${encodeURIComponent(language)}`;
+
     setIsLoading(true);
     const promise = (async () => {
       try {
-        const response = await fetch(`${API_URL}/specs/${specId}/${library}/code`);
+        const response = await fetch(url);
         if (!response.ok) {
           cacheRef.current[key] = null;
           return null;
diff --git a/app/src/pages/SpecPage.tsx b/app/src/pages/SpecPage.tsx
index de50197b3f..fa4708d8b9 100644
--- a/app/src/pages/SpecPage.tsx
+++ b/app/src/pages/SpecPage.tsx
@@ -131,14 +131,16 @@ export function SpecPage() {
     return specData.implementations.find((impl) => impl.library_id === selectedLibrary) || null;
   }, [specData, selectedLibrary]);
 
-  // Prefetch code in background when impl detail page opens
+  // Prefetch code in background when impl detail page opens. Pass urlLanguage
+  // so R impls (ggplot2 today) hit the right DB row — the API defaults to
+  // python and would 404 on an R artifact otherwise.
   useEffect(() => {
     if (specId && selectedLibrary) {
-      fetchCode(specId, selectedLibrary);
+      fetchCode(specId, selectedLibrary, urlLanguage);
     }
-  }, [specId, selectedLibrary, fetchCode]);
+  }, [specId, selectedLibrary, urlLanguage, fetchCode]);
 
-  const currentCode = specId && selectedLibrary ? getCode(specId, selectedLibrary) : null;
+  const currentCode = specId && selectedLibrary ? getCode(specId, selectedLibrary, urlLanguage) : null;
 
   // Handle library switch (in detail mode)
   const handleLibrarySelect = useCallback(
@@ -213,7 +215,7 @@ export function SpecPage() {
   const handleCopyCode = useCallback(
     async (impl: Implementation) => {
       try {
-        const code = impl.code || (specId ? await fetchCode(specId, impl.library_id) : null);
+        const code = impl.code || (specId ? await fetchCode(specId, impl.library_id, impl.language) : null);
         if (!code) return;
         await navigator.clipboard.writeText(code);
         setCodeCopied(impl.library_id);
diff --git a/tests/unit/api/test_schemas.py b/tests/unit/api/test_schemas.py
index 68bbe9a1fa..b61e6ac91c 100644
--- a/tests/unit/api/test_schemas.py
+++ b/tests/unit/api/test_schemas.py
@@ -203,4 +203,8 @@ def test_creation(self) -> None:
     def test_serialization(self) -> None:
         stats = StatsResponse(specs=10, plots=50, libraries=9)
         data = stats.model_dump()
-        assert data == {"specs": 10, "plots": 50, "libraries": 9, "lines_of_code": 0}
+        assert data == {"specs": 10, "plots": 50, "libraries": 9, "languages": 0, "lines_of_code": 0}
+
+    def test_languages_field(self) -> None:
+        stats = StatsResponse(specs=10, plots=50, libraries=10, languages=2)
+        assert stats.languages == 2
diff --git a/tests/unit/api/test_stats.py b/tests/unit/api/test_stats.py
index b7a81c7ff8..64ed785f31 100644
--- a/tests/unit/api/test_stats.py
+++ b/tests/unit/api/test_stats.py
@@ -90,6 +90,7 @@ async def test_refresh_stats_queries_db(self) -> None:
         assert result.specs == 1  # Only spec with impls
         assert result.plots == 1
         assert result.libraries == 1
+        assert result.languages == 1  # Single mock library → one distinct language_id
         assert result.lines_of_code == 42