Show starter code on leaderboard page

frontend/src/api/api.ts

@@ -23,6 +23,7 @@ export interface LeaderboardDetail {
   description: string;
   name: string;
   reference: string;
+  starter: string;
   benchmarks: Record<string, unknown>[];
   gpu_types: string[];
   rankings: Record<

frontend/src/pages/leaderboard/Leaderboard.test.tsx

@@ -30,6 +30,7 @@ const mockDeadline = "2025-06-29T17:00:00-07:00";
 const mockExpiredDeadline = "2024-01-29T12:00:00-02:00";
 const mockDescription = "Implement a 2D the given specifications";
 const mockReference = "import torch";
+const mockStarter = "def custom_kernel(data):\n    return data";
 const mockName = "test-game";
 
 describe("Leaderboard", () => {
@@ -44,12 +45,13 @@ describe("Leaderboard", () => {
 
   // -------------------- Basic rendering --------------------
 
-  it("renders name, description, gpu types; rankings visible on Rankings tab; reference visible after switching to Reference tab", () => {
+  it("renders name, description, gpu types; rankings visible on Rankings tab; starter code visible after switching to Starter Code tab", () => {
     const mockData = {
       deadline: mockDeadline,
       description: mockDescription,
       name: mockName,
       reference: mockReference,
+      starter: mockStarter,
       gpu_types: ["T1", "T2"],
       rankings: {
         T1: [
@@ -90,7 +92,7 @@ describe("Leaderboard", () => {
 
     // Tabs exist
     const rankingsTab = screen.getByRole("tab", { name: /Rankings/i });
-    const referenceTab = screen.getByRole("tab", { name: /Reference/i });
+    const referenceTab = screen.getByRole("tab", { name: /Starter Code/i });
     const submissionTab = screen.getByRole("tab", { name: /Submission/i });
     expect(rankingsTab).toBeInTheDocument();
     expect(referenceTab).toBeInTheDocument();
@@ -100,11 +102,10 @@ describe("Leaderboard", () => {
     expect(screen.getByText(/user1/)).toBeInTheDocument();
     expect(screen.getByText(/user2/)).toBeInTheDocument();
 
-    // Switch to Reference tab before asserting its content
+    // Switch to Starter Code tab before asserting its content
     fireEvent.click(referenceTab);
-    expect(screen.getByText(/Reference Implementation/i)).toBeInTheDocument();
-    expect(screen.getByText(/import/)).toBeInTheDocument();
-    expect(screen.getByText(/torch/)).toBeInTheDocument();
+    expect(screen.getByText(/Starter Submission/i)).toBeInTheDocument();
+    expect(screen.getByText(/custom_kernel/)).toBeInTheDocument();
   });
 
   it("shows loading state", () => {
@@ -276,15 +277,16 @@ describe("Leaderboard", () => {
     expect(screen.queryAllByTestId("ranking-0-row")).toHaveLength(3);
   });
 
-  // -------------------- Reference codeblock --------------------
+  // -------------------- Starter codeblock --------------------
 
-  it("show reference codeblock (after switching to Reference tab)", () => {
+  it("shows starter codeblock (after switching to Starter Code tab)", () => {
     const mockData = {
       name: "test-code",
       description: "",
       deadline: "",
       gpu_types: ["T1"],
       reference: mockReference,
+      starter: mockStarter,
       rankings: { T1: [] },
     };
 
@@ -298,23 +300,23 @@ describe("Leaderboard", () => {
 
     renderWithRouter(<Leaderboard />);
 
-    // Must switch to Reference tab first
-    fireEvent.click(screen.getByRole("tab", { name: /Reference/i }));
+    // Must switch to Starter Code tab first
+    fireEvent.click(screen.getByRole("tab", { name: /Starter Code/i }));
 
-    // Reference codeblock should be visible
-    expect(screen.getByText(/Reference Implementation/i)).toBeInTheDocument();
-    expect(screen.getByText(/import/)).toBeInTheDocument();
-    expect(screen.getByText(/torch/)).toBeInTheDocument();
+    // Starter codeblock should be visible
+    expect(screen.getByText(/Starter Submission/i)).toBeInTheDocument();
+    expect(screen.getByText(/custom_kernel/)).toBeInTheDocument();
   });
 
   // -------------------- Tabs behavior (switching) --------------------
 
-  it("starts on Rankings tab by default and can switch to Reference and back", () => {
+  it("starts on Rankings tab by default and can switch to Starter Code and back", () => {
     const mockData = {
       deadline: mockDeadline,
       description: mockDescription,
       name: mockName,
       reference: mockReference,
+      starter: mockStarter,
       gpu_types: ["T1"],
       rankings: {
         T1: [
@@ -342,11 +344,10 @@ describe("Leaderboard", () => {
     // Default selected tab should be Rankings (content visible)
     expect(screen.getByText(/user1/)).toBeInTheDocument();
 
-    // Switch to Reference tab
-    fireEvent.click(screen.getByRole("tab", { name: /Reference/i }));
-    expect(screen.getByText(/Reference Implementation/i)).toBeInTheDocument();
-    expect(screen.getByText(/import/)).toBeInTheDocument();
-    expect(screen.getByText(/torch/)).toBeInTheDocument();
+    // Switch to Starter Code tab
+    fireEvent.click(screen.getByRole("tab", { name: /Starter Code/i }));
+    expect(screen.getByText(/Starter Submission/i)).toBeInTheDocument();
+    expect(screen.getByText(/custom_kernel/)).toBeInTheDocument();
 
     // Switch back to Rankings tab
     fireEvent.click(screen.getByRole("tab", { name: /Rankings/i }));
@@ -359,6 +360,7 @@ describe("Leaderboard", () => {
       description: mockDescription,
       name: mockName,
       reference: mockReference,
+      starter: mockStarter,
       gpu_types: ["T1"],
       rankings: { T1: [] },
     };
@@ -386,6 +388,7 @@ describe("Leaderboard", () => {
       deadline: mockDeadline,
       gpu_types: ["T1"],
       reference: mockReference,
+      starter: mockStarter,
       rankings: { T1: [] },
     };
 
@@ -416,6 +419,7 @@ describe("Leaderboard", () => {
       deadline: mockDeadline,
       gpu_types: ["T1"],
       reference: mockReference,
+      starter: mockStarter,
       rankings: { T1: [] },
     };
 
@@ -451,6 +455,7 @@ describe("Leaderboard", () => {
       deadline: mockDeadline,
       gpu_types: ["T1"],
       reference: mockReference,
+      starter: mockStarter,
       rankings: { T1: [] },
     };
 
@@ -488,6 +493,7 @@ describe("Leaderboard", () => {
       deadline: mockExpiredDeadline,
       gpu_types: ["T1"],
       reference: mockReference,
+      starter: mockStarter,
       rankings: { T1: [] },
     };
 

frontend/src/pages/leaderboard/Leaderboard.tsx

@@ -284,7 +284,7 @@ const LeaderboardContent = memo(function LeaderboardContent() {
             allowScrollButtonsMobile
           >
             <Tab label="Rankings" value="rankings" {...a11yProps(0)} />
-            <Tab label="Reference" value="reference" {...a11yProps(1)} />
+            <Tab label="Starter Code" value="reference" {...a11yProps(1)} />
             <Tab label="Submission" value="submission" {...a11yProps(2)} />
           </Tabs>
         </Box>
@@ -330,13 +330,19 @@ const LeaderboardContent = memo(function LeaderboardContent() {
           </Box>
         </TabPanel>
 
-        {/* Reference Implementation Tab */}
+        {/* Starter Code Tab */}
         <TabPanel value={tab} tabKey="reference">
           <Card>
             <CardContent>
-              <CardTitle fontWeight="bold">Reference Implementation</CardTitle>
+              <CardTitle fontWeight="bold">Starter Submission</CardTitle>
               <Box>
-                <CodeBlock code={data.reference} bordered />
+                {data.starter ? (
+                  <CodeBlock code={data.starter} bordered />
+                ) : (
+                  <Typography variant="body2" color="text.secondary">
+                    No starter submission is available for this problem.
+                  </Typography>
+                )}
               </Box>
             </CardContent>
           </Card>

kernelboard/api/leaderboard.py

@@ -80,6 +80,9 @@ def to_api_leaderboard_item(data: dict[str, Any]):
     reference = leaderboard_data["reference"] or ""
     reference = reference.replace("\\n", "\n")
 
+    starter = leaderboard_data["starter"] or ""
+    starter = starter.replace("\\n", "\n")
+
     benchmarks = leaderboard_data.get("benchmarks") or []
 
     gpu_types = leaderboard_data["gpu_types"]
@@ -113,6 +116,7 @@ def to_api_leaderboard_item(data: dict[str, Any]):
         "gpu_types": gpu_types,
         "description": description,
         "reference": reference,
+        "starter": starter,
         "benchmarks": benchmarks,
         "rankings": rankings,
     }
@@ -130,6 +134,13 @@ def _get_query():
                 task->>'lang' AS lang,
                 description AS description,
                 task->'files'->>'reference.py' AS reference,
+                (
+                    SELECT code
+                    FROM leaderboard.templates
+                    WHERE leaderboard_id = %(leaderboard_id)s
+                    ORDER BY CASE WHEN lang = 'Python' THEN 0 ELSE 1 END
+                    LIMIT 1
+                ) AS starter,
                 task->'benchmarks' AS benchmarks
             FROM leaderboard.leaderboard
             WHERE id = %(leaderboard_id)s
@@ -213,6 +224,7 @@ def _get_query():
                 'lang', lang,
                 'description', description,
                 'reference', reference,
+                'starter', starter,
                 'benchmarks', benchmarks,
                 'gpu_types', (SELECT jsonb_agg(gpu_type) FROM gpu_types)
             ) FROM leaderboard_info)

kernelboard/leaderboard.py

@@ -18,7 +18,14 @@ def leaderboard(leaderboard_id: int):
                 deadline,
                 task->>'lang' AS lang,
                 description AS description,
-                task->'files'->>'reference.py' AS reference
+                task->'files'->>'reference.py' AS reference,
+                (
+                    SELECT code
+                    FROM leaderboard.templates
+                    WHERE leaderboard_id = %(leaderboard_id)s
+                    ORDER BY CASE WHEN lang = 'Python' THEN 0 ELSE 1 END
+                    LIMIT 1
+                ) AS starter
             FROM leaderboard.leaderboard
             WHERE id = %(leaderboard_id)s
         ),
@@ -86,6 +93,7 @@ def leaderboard(leaderboard_id: int):
                 'lang', lang,
                 'description', description,
                 'reference', reference,
+                'starter', starter,
                 'gpu_types', (SELECT jsonb_agg(gpu_type) FROM gpu_types)
             ) FROM leaderboard_info)
         ) AS result FROM (SELECT gpu_type FROM gpu_types) g;
@@ -118,6 +126,9 @@ def leaderboard(leaderboard_id: int):
     reference = leaderboard_data["reference"] or ""
     reference = reference.replace("\\n", "\n")
 
+    starter = leaderboard_data["starter"] or ""
+    starter = starter.replace("\\n", "\n")
+
     gpu_types = leaderboard_data["gpu_types"]
     gpu_types.sort()
 
@@ -150,6 +161,6 @@ def leaderboard(leaderboard_id: int):
         lang=lang,
         gpu_types=gpu_types,
         description=description,
-        reference=reference,
+        reference=starter,
         rankings=rankings,
     )