CodeBench: Go-tuki — Chi + SQLite + httptest

- Golden example: todo-go/ (6/6 testit läpi)
- todo-go.md golden reference
- prompts/code-go.md koodigenerointi-prompti
- Dockerfile.go-test (golang:1.23-alpine)
- benchmark.mjs: LANG_CONFIG, parseTestOutput, prompt/golden-valinta Go:lle
- Käyttö: node benchmark.mjs --lang go --models qwen2.5-coder:32b

kipina-codebench/Dockerfile.go-test

@@ -0,0 +1,4 @@
+FROM golang:1.23-alpine
+RUN apk add --no-cache gcc musl-dev
+WORKDIR /work
+ENTRYPOINT ["sh", "-c", "cp -r /src/* . && go test -v -count=1 ./... 2>&1"]

kipina-codebench/benchmark.mjs

@@ -34,7 +34,7 @@ const OUTPUT_DIR = arg('output', `/tmp/kipina-benchmark/${TIMESTAMP}`);
 const RESULTS_DIR = join(__dirname, 'results');
 const THINK_MODE = args.includes('--think');
 const COMPACT_MODE = args.includes('--compact');
-const LANG = arg('lang', 'python');  // python | rust
+const LANG = arg('lang', 'python');  // python | rust | go
 const ROUNDS = parseInt(arg('rounds', '1'));  // 1-10 toistoa
 const MAX_FIX_ROUNDS = 2;
 
@@ -53,11 +53,12 @@ const PROFILES = JSON.parse(readFileSync(join(__dirname, 'profiles.json'), 'utf-
 function getGoldenForModel(model) {
     const modelConf = PROFILES.models[model];
     const goldenFile = modelConf?.golden || 'todo.md';
-    // Rust-kielelle vaihda .md → -rs.md (todo.md → todo-rs.md)
+    // Kielispesifi golden: todo.md → todo-rs.md / todo-go.md
-    if (LANG === 'rust') {
+    const langSuffix = { rust: '-rs', go: '-go' }[LANG];
-        const rsFile = goldenFile.replace(/\.md$/, '-rs.md');
+    if (langSuffix) {
-        const rsPath = join(GOLDEN_DIR, rsFile);
+        const langFile = goldenFile.replace(/\.md$/, `${langSuffix}.md`);
-        if (existsSync(rsPath)) return rsFile;
+        const langPath = join(GOLDEN_DIR, langFile);
+        if (existsSync(langPath)) return langFile;
     }
     return goldenFile;
 }
@@ -66,8 +67,8 @@ function getCodePromptForModel(model) {
     const modelConf = PROFILES.models[model];
     const profile = modelConf?.profile || PROFILES.default_profile;
     const promptName = modelConf?.prompt || PROFILES.profiles[profile]?.prompt || 'code';
-    const suffix = LANG === 'rust' ? '-rs' : '';
+    const suffix = { rust: '-rs', go: '-go' }[LANG] || '';
-    // Yritä kielispesifistä ensin (code-small-rs), sitten perus (code-small)
+    // Yritä kielispesifistä ensin (code-small-rs, code-go), sitten perus (code-small)
     const candidates = [`${promptName}${suffix}`, promptName, `code${suffix}`, 'code'];
     for (const name of candidates) {
         const path = join(__dirname, 'prompts', `${name}.md`);
@@ -91,18 +92,24 @@ const LANG_CONFIG = {
         required: ['Cargo.toml', 'src/models.rs', 'src/handlers.rs', 'src/lib.rs', 'src/main.rs', 'tests/api_test.rs'],
         dockerImage: 'kipina-cargo-test',
     },
+    go: {
+        goldenDir: 'todo-go',
+        files: ['go.mod', 'models.go', 'handlers.go', 'main.go', 'handlers_test.go'],
+        required: ['go.mod', 'models.go', 'handlers.go', 'main.go', 'handlers_test.go'],
+        dockerImage: 'kipina-go-test',
+    },
 };
 const LCONF = LANG_CONFIG[LANG] || LANG_CONFIG.python;
 
 function loadGoldenExample(model) {
     // --compact: käytä tiivistettyä templaattia
     if (COMPACT_MODE) {
-        const compactFile = LANG === 'rust' ? 'golden-compact-rs.md' : 'golden-compact-py.md';
+        const compactFile = { rust: 'golden-compact-rs.md', go: 'golden-compact-go.md' }[LANG] || 'golden-compact-py.md';
         const compactPath = join(__dirname, 'prompts', compactFile);
         if (existsSync(compactPath)) return '\n' + readFileSync(compactPath, 'utf-8').trim() + '\n';
     }
     // Mallikohtainen golden example profiilista
-    const goldenFile = model ? getGoldenForModel(model) : (LANG === 'rust' ? 'todo-rs.md' : 'todo.md');
+    const goldenFile = model ? getGoldenForModel(model) : ({ rust: 'todo-rs.md', go: 'todo-go.md' }[LANG] || 'todo.md');
     const mdPath = join(GOLDEN_DIR, goldenFile);
     if (existsSync(mdPath)) return '\n' + readFileSync(mdPath, 'utf-8').trim() + '\n';
     // Fallback: erilliset tiedostot
@@ -201,7 +208,13 @@ function parseTestOutput(output) {
         const failed = parseInt(cargoMatch[2]);
         return { testsPassed: passed, testsFailed: failed, testsTotal: passed + failed };
     }
-    // Cargo compilation error: count "error[E" occurrences
+    // Go test: "--- PASS:" / "--- FAIL:"
+    const goPassed = (output.match(/--- PASS:/g) || []).length;
+    const goFailed = (output.match(/--- FAIL:/g) || []).length;
+    if (goPassed + goFailed > 0) {
+        return { testsPassed: goPassed, testsFailed: goFailed, testsTotal: goPassed + goFailed };
+    }
+    // Cargo/Go compilation error: count "error[E" or Go compile errors
     const compileErrors = (output.match(/error\[E\d+\]/g) || []).length;
     if (compileErrors > 0) {
         return { testsPassed: 0, testsFailed: compileErrors, testsTotal: compileErrors };
@@ -333,7 +346,7 @@ async function runPipeline(model, scenario) {
         // 3. LLM-koodigenerointi
         const fileCount = LCONF.required.length;
         const goldenExample = loadGoldenExample(model);
-        const codeTokens = LANG === 'rust' ? 12288 : 8192;
+        const codeTokens = LANG === 'rust' ? 12288 : LANG === 'go' ? 10240 : 8192;
         let files;
 
         // Orkestrointi: pilko entiteetti kerrallaan pienille malleille
@@ -454,7 +467,7 @@ async function runPipeline(model, scenario) {
         result.fixRounds = fixRound;
 
         // 5. Testit Docker-kontissa + itsekorjaava looppi (Taso 4)
-        const testLabel = LANG === 'rust' ? 'Cargo test' : 'Pytest';
+        const testLabel = { rust: 'Cargo test', go: 'Go test', python: 'Pytest' }[LANG] || 'Test';
         const dockerTimeout = LANG === 'rust' ? 300000 : 120000;
         const MAX_TEST_FIX = 3;
         let bestFiles = { ...files };       // Paras versio tiedostoista
@@ -538,13 +551,13 @@ async function runPipeline(model, scenario) {
             }
 
             // Itsekorjaus: syötä virhe + koodi mallille
-            const errorLines = testOut.split('\n').filter(l => /^E |FAILED|ERROR|error\[E/.test(l)).slice(0, 20).join('\n');
+            const errorLines = testOut.split('\n').filter(l => /^E |FAILED|ERROR|error\[E|--- FAIL|panic:|\.go:\d+/.test(l)).slice(0, 20).join('\n');
             if (!errorLines) break;  // Ei parsittavia virheitä
 
             console.log(`    [5/5] Itsekorjaus: ${result.testsFailed || 'virhe'}...`);
             const allCode = Object.entries(files).map(([fn, c]) => `=== ${fn} ===\n${c}`).join('\n\n');
             const fixPrompt = `The following test errors occurred. Fix the code so ALL tests pass. Return ALL files with === markers.\n\nERRORS:\n${errorLines}\n\nCURRENT CODE:\n${allCode}`;
-            const fixResp = await ollamaChat(model, fixPrompt, CODE_SYSTEM, LANG === 'rust' ? 12288 : 8192);
+            const fixResp = await ollamaChat(model, fixPrompt, CODE_SYSTEM, LANG === 'rust' ? 12288 : LANG === 'go' ? 10240 : 8192);
             timings.push(fixResp);
 
             const fixedFiles = parseGeneratedFiles(fixResp.text);

kipina-codebench/golden-examples/todo-go.md

@@ -0,0 +1,466 @@
+# Todo — reference implementation (Go + Chi + SQLite)
+
+This is a complete example. Generate equivalent structure for the given project.
+Use ONLY the fields from the JSON spec — do not add extras.
+
+## go.mod
+
+Chi v5 router, modernc.org/sqlite (pure Go, no CGO).
+
+```
+module todo-go
+
+go 1.23.0
+
+toolchain go1.23.12
+
+require (
+	github.com/go-chi/chi/v5 v5.2.1
+	modernc.org/sqlite v1.37.1
+)
+
+require (
+	github.com/dustin/go-humanize v1.0.1 // indirect
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/ncruces/go-strftime v0.1.9 // indirect
+	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
+	golang.org/x/exp v0.0.0-20250408133849-7e4ce0ab07d0 // indirect
+	golang.org/x/sys v0.33.0 // indirect
+	modernc.org/libc v1.65.7 // indirect
+	modernc.org/mathutil v1.7.1 // indirect
+	modernc.org/memory v1.11.0 // indirect
+)
+```
+
+## models.go
+
+Data structs: Todo (full row), CreateTodo (POST), UpdateTodo (PUT, all fields optional pointers).
+
+```go
+package main
+
+// Todo represents a task with priority and status tracking.
+type Todo struct {
+	ID          int64   `json:"id"`
+	Title       string  `json:"title"`
+	Description *string `json:"description,omitempty"`
+	DueDate     *string `json:"due_date,omitempty"`
+	Priority    int64   `json:"priority"`
+	Status      string  `json:"status"`
+}
+
+// CreateTodo is the request body for creating a new todo.
+type CreateTodo struct {
+	Title       string  `json:"title"`
+	Description *string `json:"description,omitempty"`
+	DueDate     *string `json:"due_date,omitempty"`
+	Priority    *int64  `json:"priority,omitempty"`
+	Status      *string `json:"status,omitempty"`
+}
+
+// UpdateTodo is the request body for updating an existing todo.
+type UpdateTodo struct {
+	Title       *string `json:"title,omitempty"`
+	Description *string `json:"description,omitempty"`
+	DueDate     *string `json:"due_date,omitempty"`
+	Priority    *int64  `json:"priority,omitempty"`
+	Status      *string `json:"status,omitempty"`
+}
+```
+
+## handlers.go
+
+CRUD handlers as closures taking *sql.DB. INSERT/UPDATE use RETURNING, sql.ErrNoRows for 404.
+
+```go
+package main
+
+import (
+	"database/sql"
+	"encoding/json"
+	"net/http"
+	"strconv"
+
+	"github.com/go-chi/chi/v5"
+)
+
+func createTodo(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		var input CreateTodo
+		if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+		priority := int64(1)
+		if input.Priority != nil {
+			priority = *input.Priority
+		}
+		status := "pending"
+		if input.Status != nil {
+			status = *input.Status
+		}
+		var todo Todo
+		err := db.QueryRow(
+			`INSERT INTO todos (title, description, due_date, priority, status)
+			 VALUES (?, ?, ?, ?, ?)
+			 RETURNING id, title, description, due_date, priority, status`,
+			input.Title, input.Description, input.DueDate, priority, status,
+		).Scan(&todo.ID, &todo.Title, &todo.Description, &todo.DueDate, &todo.Priority, &todo.Status)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusCreated)
+		json.NewEncoder(w).Encode(todo)
+	}
+}
+
+func listTodos(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		rows, err := db.Query("SELECT id, title, description, due_date, priority, status FROM todos")
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		defer rows.Close()
+		var todos []Todo
+		for rows.Next() {
+			var t Todo
+			if err := rows.Scan(&t.ID, &t.Title, &t.Description, &t.DueDate, &t.Priority, &t.Status); err != nil {
+				http.Error(w, err.Error(), http.StatusInternalServerError)
+				return
+			}
+			todos = append(todos, t)
+		}
+		if todos == nil {
+			todos = []Todo{}
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(todos)
+	}
+}
+
+func getTodo(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+		var todo Todo
+		err := db.QueryRow(
+			"SELECT id, title, description, due_date, priority, status FROM todos WHERE id = ?", id,
+		).Scan(&todo.ID, &todo.Title, &todo.Description, &todo.DueDate, &todo.Priority, &todo.Status)
+		if err == sql.ErrNoRows {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(todo)
+	}
+}
+
+func updateTodo(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+		var existing Todo
+		err := db.QueryRow(
+			"SELECT id, title, description, due_date, priority, status FROM todos WHERE id = ?", id,
+		).Scan(&existing.ID, &existing.Title, &existing.Description, &existing.DueDate, &existing.Priority, &existing.Status)
+		if err == sql.ErrNoRows {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		var input UpdateTodo
+		if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+		if input.Title != nil {
+			existing.Title = *input.Title
+		}
+		if input.Description != nil {
+			existing.Description = input.Description
+		}
+		if input.DueDate != nil {
+			existing.DueDate = input.DueDate
+		}
+		if input.Priority != nil {
+			existing.Priority = *input.Priority
+		}
+		if input.Status != nil {
+			existing.Status = *input.Status
+		}
+		var updated Todo
+		err = db.QueryRow(
+			`UPDATE todos SET title = ?, description = ?, due_date = ?, priority = ?, status = ?
+			 WHERE id = ?
+			 RETURNING id, title, description, due_date, priority, status`,
+			existing.Title, existing.Description, existing.DueDate, existing.Priority, existing.Status, id,
+		).Scan(&updated.ID, &updated.Title, &updated.Description, &updated.DueDate, &updated.Priority, &updated.Status)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(updated)
+	}
+}
+
+func deleteTodo(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+		result, err := db.Exec("DELETE FROM todos WHERE id = ?", id)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		rows, _ := result.RowsAffected()
+		if rows == 0 {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+	}
+}
+```
+
+## main.go
+
+Entry point: SQLite connection, table init, Chi router on port 3000.
+
+```go
+package main
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+	"net/http"
+
+	"github.com/go-chi/chi/v5"
+	_ "modernc.org/sqlite"
+)
+
+// InitDB creates tables if they don't exist.
+func InitDB(db *sql.DB) {
+	_, err := db.Exec(`CREATE TABLE IF NOT EXISTS todos (
+		id          INTEGER PRIMARY KEY AUTOINCREMENT,
+		title       TEXT NOT NULL,
+		description TEXT,
+		due_date    TEXT,
+		priority    INTEGER NOT NULL DEFAULT 1,
+		status      TEXT NOT NULL DEFAULT 'pending'
+	)`)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+// NewRouter creates a chi router with all routes.
+func NewRouter(db *sql.DB) http.Handler {
+	r := chi.NewRouter()
+	r.Post("/todos", createTodo(db))
+	r.Get("/todos", listTodos(db))
+	r.Get("/todos/{id}", getTodo(db))
+	r.Put("/todos/{id}", updateTodo(db))
+	r.Delete("/todos/{id}", deleteTodo(db))
+	return r
+}
+
+func main() {
+	db, err := sql.Open("sqlite", "file:app.db?mode=rwc")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer db.Close()
+	InitDB(db)
+
+	fmt.Println("Server running: http://127.0.0.1:3000")
+	log.Fatal(http.ListenAndServe("127.0.0.1:3000", NewRouter(db)))
+}
+```
+
+## handlers_test.go
+
+Integration tests: setupTestServer with httptest.NewServer + :memory: SQLite, unique data per test.
+
+```go
+package main
+
+import (
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	_ "modernc.org/sqlite"
+)
+
+func setupTestServer(t *testing.T) (*httptest.Server, *sql.DB) {
+	t.Helper()
+	db, err := sql.Open("sqlite", ":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	InitDB(db)
+	return httptest.NewServer(NewRouter(db)), db
+}
+
+func TestCreateTodo(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, err := http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Buy groceries","priority":2}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusCreated {
+		t.Fatalf("expected 201, got %d", resp.StatusCode)
+	}
+	var body map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&body)
+	if body["title"] != "Buy groceries" {
+		t.Fatalf("expected title 'Buy groceries', got %v", body["title"])
+	}
+	if body["id"] == nil {
+		t.Fatal("expected id to be present")
+	}
+}
+
+func TestListTodos(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Listable task"}`))
+
+	resp, err := http.Get(ts.URL + "/todos")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+	var body []map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&body)
+	if len(body) < 1 {
+		t.Fatal("expected at least 1 todo")
+	}
+}
+
+func TestGetTodoByID(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, _ := http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Fetchable task"}`))
+	var created map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&created)
+	resp.Body.Close()
+
+	id := created["id"].(float64)
+	resp, err := http.Get(ts.URL + "/todos/" + fmt.Sprintf("%.0f", id))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+	var body map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&body)
+	if body["id"] != id {
+		t.Fatalf("expected id %.0f, got %v", id, body["id"])
+	}
+}
+
+func TestGetTodoNotFound(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, err := http.Get(ts.URL + "/todos/99999")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", resp.StatusCode)
+	}
+}
+
+func TestUpdateTodo(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, _ := http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Old title"}`))
+	var created map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&created)
+	resp.Body.Close()
+
+	id := created["id"].(float64)
+	req, _ := http.NewRequest(http.MethodPut, ts.URL+"/todos/"+fmt.Sprintf("%.0f", id),
+		strings.NewReader(`{"title":"New title"}`))
+	req.Header.Set("Content-Type", "application/json")
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+	var body map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&body)
+	if body["title"] != "New title" {
+		t.Fatalf("expected 'New title', got %v", body["title"])
+	}
+}
+
+func TestDeleteTodo(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, _ := http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Deletable task"}`))
+	var created map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&created)
+	resp.Body.Close()
+
+	id := created["id"].(float64)
+	req, _ := http.NewRequest(http.MethodDelete, ts.URL+"/todos/"+fmt.Sprintf("%.0f", id), nil)
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d", resp.StatusCode)
+	}
+
+	resp, _ = http.Get(ts.URL + "/todos/" + fmt.Sprintf("%.0f", id))
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusNotFound {
+		t.Fatalf("expected 404 after delete, got %d", resp.StatusCode)
+	}
+}
+```

kipina-codebench/golden-examples/todo-go/go.mod

@@ -0,0 +1,23 @@
+module todo-go
+
+go 1.23.0
+
+toolchain go1.23.12
+
+require (
+	github.com/go-chi/chi/v5 v5.2.1
+	modernc.org/sqlite v1.37.1
+)
+
+require (
+	github.com/dustin/go-humanize v1.0.1 // indirect
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/ncruces/go-strftime v0.1.9 // indirect
+	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
+	golang.org/x/exp v0.0.0-20250408133849-7e4ce0ab07d0 // indirect
+	golang.org/x/sys v0.33.0 // indirect
+	modernc.org/libc v1.65.7 // indirect
+	modernc.org/mathutil v1.7.1 // indirect
+	modernc.org/memory v1.11.0 // indirect
+)

kipina-codebench/golden-examples/todo-go/go.sum

@@ -0,0 +1,49 @@
+github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
+github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
+github.com/go-chi/chi/v5 v5.2.1 h1:KOIHODQj58PmL80G2Eak4WdvUzjSJSm0vG72crDCqb8=
+github.com/go-chi/chi/v5 v5.2.1/go.mod h1:L2yAIGWB3H+phAw1NxKwWM+7eUH/lU8pOMm5hHcoops=
+github.com/google/pprof v0.0.0-20250317173921-a4b03ec1a45e h1:ijClszYn+mADRFY17kjQEVQ1XRhq2/JR1M3sGqeJoxs=
+github.com/google/pprof v0.0.0-20250317173921-a4b03ec1a45e/go.mod h1:boTsfXsheKC2y+lKOCMpSfarhxDeIzfZG1jqGcPl3cA=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/ncruces/go-strftime v0.1.9 h1:bY0MQC28UADQmHmaF5dgpLmImcShSi2kHU9XLdhx/f4=
+github.com/ncruces/go-strftime v0.1.9/go.mod h1:Fwc5htZGVVkseilnfgOVb9mKy6w1naJmn9CehxcKcls=
+github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec h1:W09IVJc94icq4NjY3clb7Lk8O1qJ8BdBEF8z0ibU0rE=
+github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec/go.mod h1:qqbHyh8v60DhA7CoWK5oRCqLrMHRGoxYCSS9EjAz6Eo=
+golang.org/x/exp v0.0.0-20250408133849-7e4ce0ab07d0 h1:R84qjqJb5nVJMxqWYb3np9L5ZsaDtB+a39EqjV0JSUM=
+golang.org/x/exp v0.0.0-20250408133849-7e4ce0ab07d0/go.mod h1:S9Xr4PYopiDyqSyp5NjCrhFrqg6A5zA2E/iPHPhqnS8=
+golang.org/x/mod v0.24.0 h1:ZfthKaKaT4NrhGVZHO1/WDTwGES4De8KtWO0SIbNJMU=
+golang.org/x/mod v0.24.0/go.mod h1:IXM97Txy2VM4PJ3gI61r1YEk/gAj6zAHN3AdZt6S9Ww=
+golang.org/x/sync v0.14.0 h1:woo0S4Yywslg6hp4eUFjTVOyKt0RookbpAHG4c1HmhQ=
+golang.org/x/sync v0.14.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.33.0 h1:q3i8TbbEz+JRD9ywIRlyRAQbM0qF7hu24q3teo2hbuw=
+golang.org/x/sys v0.33.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
+golang.org/x/tools v0.33.0 h1:4qz2S3zmRxbGIhDIAgjxvFutSvH5EfnsYrRBj0UI0bc=
+golang.org/x/tools v0.33.0/go.mod h1:CIJMaWEY88juyUfo7UbgPqbC8rU2OqfAV1h2Qp0oMYI=
+modernc.org/cc/v4 v4.26.1 h1:+X5NtzVBn0KgsBCBe+xkDC7twLb/jNVj9FPgiwSQO3s=
+modernc.org/cc/v4 v4.26.1/go.mod h1:uVtb5OGqUKpoLWhqwNQo/8LwvoiEBLvZXIQ/SmO6mL0=
+modernc.org/ccgo/v4 v4.28.0 h1:rjznn6WWehKq7dG4JtLRKxb52Ecv8OUGah8+Z/SfpNU=
+modernc.org/ccgo/v4 v4.28.0/go.mod h1:JygV3+9AV6SmPhDasu4JgquwU81XAKLd3OKTUDNOiKE=
+modernc.org/fileutil v1.3.1 h1:8vq5fe7jdtEvoCf3Zf9Nm0Q05sH6kGx0Op2CPx1wTC8=
+modernc.org/fileutil v1.3.1/go.mod h1:HxmghZSZVAz/LXcMNwZPA/DRrQZEVP9VX0V4LQGQFOc=
+modernc.org/gc/v2 v2.6.5 h1:nyqdV8q46KvTpZlsw66kWqwXRHdjIlJOhG6kxiV/9xI=
+modernc.org/gc/v2 v2.6.5/go.mod h1:YgIahr1ypgfe7chRuJi2gD7DBQiKSLMPgBQe9oIiito=
+modernc.org/libc v1.65.7 h1:Ia9Z4yzZtWNtUIuiPuQ7Qf7kxYrxP1/jeHZzG8bFu00=
+modernc.org/libc v1.65.7/go.mod h1:011EQibzzio/VX3ygj1qGFt5kMjP0lHb0qCW5/D/pQU=
+modernc.org/mathutil v1.7.1 h1:GCZVGXdaN8gTqB1Mf/usp1Y/hSqgI2vAGGP4jZMCxOU=
+modernc.org/mathutil v1.7.1/go.mod h1:4p5IwJITfppl0G4sUEDtCr4DthTaT47/N3aT6MhfgJg=
+modernc.org/memory v1.11.0 h1:o4QC8aMQzmcwCK3t3Ux/ZHmwFPzE6hf2Y5LbkRs+hbI=
+modernc.org/memory v1.11.0/go.mod h1:/JP4VbVC+K5sU2wZi9bHoq2MAkCnrt2r98UGeSK7Mjw=
+modernc.org/opt v0.1.4 h1:2kNGMRiUjrp4LcaPuLY2PzUfqM/w9N23quVwhKt5Qm8=
+modernc.org/opt v0.1.4/go.mod h1:03fq9lsNfvkYSfxrfUhZCWPk1lm4cq4N+Bh//bEtgns=
+modernc.org/sortutil v1.2.1 h1:+xyoGf15mM3NMlPDnFqrteY07klSFxLElE2PVuWIJ7w=
+modernc.org/sortutil v1.2.1/go.mod h1:7ZI3a3REbai7gzCLcotuw9AC4VZVpYMjDzETGsSMqJE=
+modernc.org/sqlite v1.37.1 h1:EgHJK/FPoqC+q2YBXg7fUmES37pCHFc97sI7zSayBEs=
+modernc.org/sqlite v1.37.1/go.mod h1:XwdRtsE1MpiBcL54+MbKcaDvcuej+IYSMfLN6gSKV8g=
+modernc.org/strutil v1.2.1 h1:UneZBkQA+DX2Rp35KcM69cSsNES9ly8mQWD71HKlOA0=
+modernc.org/strutil v1.2.1/go.mod h1:EHkiggD70koQxjVdSBM3JKM7k6L0FbGE5eymy9i3B9A=
+modernc.org/token v1.1.0 h1:Xl7Ap9dKaEs5kLoOQeQmPWevfnk/DM5qcLcYlA8ys6Y=
+modernc.org/token v1.1.0/go.mod h1:UGzOrNV1mAFSEB63lOFHIpNRUVMvYTc6yu1SMY/XTDM=

kipina-codebench/golden-examples/todo-go/handlers.go

@@ -0,0 +1,155 @@
+package main
+
+import (
+	"database/sql"
+	"encoding/json"
+	"net/http"
+	"strconv"
+
+	"github.com/go-chi/chi/v5"
+)
+
+func createTodo(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		var input CreateTodo
+		if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+		priority := int64(1)
+		if input.Priority != nil {
+			priority = *input.Priority
+		}
+		status := "pending"
+		if input.Status != nil {
+			status = *input.Status
+		}
+		var todo Todo
+		err := db.QueryRow(
+			`INSERT INTO todos (title, description, due_date, priority, status)
+			 VALUES (?, ?, ?, ?, ?)
+			 RETURNING id, title, description, due_date, priority, status`,
+			input.Title, input.Description, input.DueDate, priority, status,
+		).Scan(&todo.ID, &todo.Title, &todo.Description, &todo.DueDate, &todo.Priority, &todo.Status)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusCreated)
+		json.NewEncoder(w).Encode(todo)
+	}
+}
+
+func listTodos(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		rows, err := db.Query("SELECT id, title, description, due_date, priority, status FROM todos")
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		defer rows.Close()
+		var todos []Todo
+		for rows.Next() {
+			var t Todo
+			if err := rows.Scan(&t.ID, &t.Title, &t.Description, &t.DueDate, &t.Priority, &t.Status); err != nil {
+				http.Error(w, err.Error(), http.StatusInternalServerError)
+				return
+			}
+			todos = append(todos, t)
+		}
+		if todos == nil {
+			todos = []Todo{}
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(todos)
+	}
+}
+
+func getTodo(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+		var todo Todo
+		err := db.QueryRow(
+			"SELECT id, title, description, due_date, priority, status FROM todos WHERE id = ?", id,
+		).Scan(&todo.ID, &todo.Title, &todo.Description, &todo.DueDate, &todo.Priority, &todo.Status)
+		if err == sql.ErrNoRows {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(todo)
+	}
+}
+
+func updateTodo(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+		var existing Todo
+		err := db.QueryRow(
+			"SELECT id, title, description, due_date, priority, status FROM todos WHERE id = ?", id,
+		).Scan(&existing.ID, &existing.Title, &existing.Description, &existing.DueDate, &existing.Priority, &existing.Status)
+		if err == sql.ErrNoRows {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		var input UpdateTodo
+		if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+		if input.Title != nil {
+			existing.Title = *input.Title
+		}
+		if input.Description != nil {
+			existing.Description = input.Description
+		}
+		if input.DueDate != nil {
+			existing.DueDate = input.DueDate
+		}
+		if input.Priority != nil {
+			existing.Priority = *input.Priority
+		}
+		if input.Status != nil {
+			existing.Status = *input.Status
+		}
+		var updated Todo
+		err = db.QueryRow(
+			`UPDATE todos SET title = ?, description = ?, due_date = ?, priority = ?, status = ?
+			 WHERE id = ?
+			 RETURNING id, title, description, due_date, priority, status`,
+			existing.Title, existing.Description, existing.DueDate, existing.Priority, existing.Status, id,
+		).Scan(&updated.ID, &updated.Title, &updated.Description, &updated.DueDate, &updated.Priority, &updated.Status)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(updated)
+	}
+}
+
+func deleteTodo(db *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+		result, err := db.Exec("DELETE FROM todos WHERE id = ?", id)
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		rows, _ := result.RowsAffected()
+		if rows == 0 {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+	}
+}

kipina-codebench/golden-examples/todo-go/handlers_test.go

@@ -0,0 +1,171 @@
+package main
+
+import (
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	_ "modernc.org/sqlite"
+)
+
+func setupTestServer(t *testing.T) (*httptest.Server, *sql.DB) {
+	t.Helper()
+	db, err := sql.Open("sqlite", ":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	InitDB(db)
+	return httptest.NewServer(NewRouter(db)), db
+}
+
+func TestCreateTodo(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, err := http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Buy groceries","priority":2}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusCreated {
+		t.Fatalf("expected 201, got %d", resp.StatusCode)
+	}
+	var body map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&body)
+	if body["title"] != "Buy groceries" {
+		t.Fatalf("expected title 'Buy groceries', got %v", body["title"])
+	}
+	if body["id"] == nil {
+		t.Fatal("expected id to be present")
+	}
+}
+
+func TestListTodos(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Listable task"}`))
+
+	resp, err := http.Get(ts.URL + "/todos")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+	var body []map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&body)
+	if len(body) < 1 {
+		t.Fatal("expected at least 1 todo")
+	}
+}
+
+func TestGetTodoByID(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, _ := http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Fetchable task"}`))
+	var created map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&created)
+	resp.Body.Close()
+
+	id := created["id"].(float64)
+	resp, err := http.Get(ts.URL + "/todos/" + fmt.Sprintf("%.0f", id))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+	var body map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&body)
+	if body["id"] != id {
+		t.Fatalf("expected id %.0f, got %v", id, body["id"])
+	}
+}
+
+func TestGetTodoNotFound(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, err := http.Get(ts.URL + "/todos/99999")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", resp.StatusCode)
+	}
+}
+
+func TestUpdateTodo(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, _ := http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Old title"}`))
+	var created map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&created)
+	resp.Body.Close()
+
+	id := created["id"].(float64)
+	req, _ := http.NewRequest(http.MethodPut, ts.URL+"/todos/"+fmt.Sprintf("%.0f", id),
+		strings.NewReader(`{"title":"New title"}`))
+	req.Header.Set("Content-Type", "application/json")
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+	var body map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&body)
+	if body["title"] != "New title" {
+		t.Fatalf("expected 'New title', got %v", body["title"])
+	}
+}
+
+func TestDeleteTodo(t *testing.T) {
+	ts, db := setupTestServer(t)
+	defer ts.Close()
+	defer db.Close()
+
+	resp, _ := http.Post(ts.URL+"/todos", "application/json",
+		strings.NewReader(`{"title":"Deletable task"}`))
+	var created map[string]interface{}
+	json.NewDecoder(resp.Body).Decode(&created)
+	resp.Body.Close()
+
+	id := created["id"].(float64)
+	req, _ := http.NewRequest(http.MethodDelete, ts.URL+"/todos/"+fmt.Sprintf("%.0f", id), nil)
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d", resp.StatusCode)
+	}
+
+	resp, _ = http.Get(ts.URL + "/todos/" + fmt.Sprintf("%.0f", id))
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusNotFound {
+		t.Fatalf("expected 404 after delete, got %d", resp.StatusCode)
+	}
+}

kipina-codebench/golden-examples/todo-go/main.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+	"net/http"
+
+	"github.com/go-chi/chi/v5"
+	_ "modernc.org/sqlite"
+)
+
+// InitDB creates tables if they don't exist.
+func InitDB(db *sql.DB) {
+	_, err := db.Exec(`CREATE TABLE IF NOT EXISTS todos (
+		id          INTEGER PRIMARY KEY AUTOINCREMENT,
+		title       TEXT NOT NULL,
+		description TEXT,
+		due_date    TEXT,
+		priority    INTEGER NOT NULL DEFAULT 1,
+		status      TEXT NOT NULL DEFAULT 'pending'
+	)`)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+// NewRouter creates a chi router with all routes.
+func NewRouter(db *sql.DB) http.Handler {
+	r := chi.NewRouter()
+	r.Post("/todos", createTodo(db))
+	r.Get("/todos", listTodos(db))
+	r.Get("/todos/{id}", getTodo(db))
+	r.Put("/todos/{id}", updateTodo(db))
+	r.Delete("/todos/{id}", deleteTodo(db))
+	return r
+}
+
+func main() {
+	db, err := sql.Open("sqlite", "file:app.db?mode=rwc")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer db.Close()
+	InitDB(db)
+
+	fmt.Println("Server running: http://127.0.0.1:3000")
+	log.Fatal(http.ListenAndServe("127.0.0.1:3000", NewRouter(db)))
+}

kipina-codebench/golden-examples/todo-go/models.go

@@ -0,0 +1,29 @@
+package main
+
+// Todo represents a task with priority and status tracking.
+type Todo struct {
+	ID          int64   `json:"id"`
+	Title       string  `json:"title"`
+	Description *string `json:"description,omitempty"`
+	DueDate     *string `json:"due_date,omitempty"`
+	Priority    int64   `json:"priority"`
+	Status      string  `json:"status"`
+}
+
+// CreateTodo is the request body for creating a new todo.
+type CreateTodo struct {
+	Title       string  `json:"title"`
+	Description *string `json:"description,omitempty"`
+	DueDate     *string `json:"due_date,omitempty"`
+	Priority    *int64  `json:"priority,omitempty"`
+	Status      *string `json:"status,omitempty"`
+}
+
+// UpdateTodo is the request body for updating an existing todo.
+type UpdateTodo struct {
+	Title       *string `json:"title,omitempty"`
+	Description *string `json:"description,omitempty"`
+	DueDate     *string `json:"due_date,omitempty"`
+	Priority    *int64  `json:"priority,omitempty"`
+	Status      *string `json:"status,omitempty"`
+}

kipina-codebench/prompts/code-go.md

@@ -0,0 +1,69 @@
+You are a Go backend developer. Generate a Chi web project with SQLite.
+
+Given the project requirements, JSON specification, and a REFERENCE IMPLEMENTATION, generate these files:
+
+1. go.mod — module declaration, go-chi/chi/v5, modernc.org/sqlite
+2. models.go — Structs with json tags
+3. handlers.go — Handler closures for each CRUD endpoint
+4. main.go — Entry point with InitDB(), NewRouter(), main()
+5. handlers_test.go — Integration tests using httptest against in-memory SQLite
+
+Do NOT generate any other files. Do NOT generate go.sum.
+
+OUTPUT FORMAT — use these exact markers to separate files:
+
+=== go.mod ===
+<module content>
+
+=== models.go ===
+<go code>
+
+=== handlers.go ===
+<go code>
+
+=== main.go ===
+<go code>
+
+=== handlers_test.go ===
+<go code>
+
+DOCUMENTATION — structs get // one-line comments. Keep it brief.
+
+RULES:
+- Follow the REFERENCE IMPLEMENTATION patterns exactly
+- Chi router with chi.URLParam(r, "param") for path parameters
+- database/sql + modernc.org/sqlite (pure Go driver, no CGO required)
+- Import the driver as blank import: _ "modernc.org/sqlite"
+- Handlers are closures: func handler(db *sql.DB) http.HandlerFunc
+- INSERT/UPDATE queries use RETURNING clause to get the row back via QueryRow + Scan
+- POST returns 201 (http.StatusCreated), DELETE returns 204 (http.StatusNoContent), GET missing returns 404
+- Use sql.ErrNoRows for not-found checks: if err == sql.ErrNoRows { ... }
+- No compile-time query macros — use db.QueryRow(), db.Query(), db.Exec() directly
+- Empty slice not nil for list endpoints: if items == nil { items = []Item{} }
+- Optional fields use pointer types (*string, *int64) with json tag omitempty
+- Set Content-Type header: w.Header().Set("Content-Type", "application/json")
+- Parse path ID with strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+- InitDB uses log.Fatal on error, NewRouter returns http.Handler
+- main() opens "file:app.db?mode=rwc" and listens on 127.0.0.1:3000
+- No markdown fences inside file content — just raw code
+- You MUST generate ALL 5 files. Do not stop early.
+
+TESTS — follow this exact setupTestServer pattern:
+
+func setupTestServer(t *testing.T) (*httptest.Server, *sql.DB) {
+    t.Helper()
+    db, err := sql.Open("sqlite", ":memory:")
+    if err != nil {
+        t.Fatal(err)
+    }
+    InitDB(db)
+    return httptest.NewServer(NewRouter(db)), db
+}
+
+- Each test function calls setupTestServer(t) to get (ts, db)
+- defer ts.Close() and defer db.Close() in every test
+- Use standard library: http.Post, http.Get, http.NewRequest for PUT/DELETE
+- Use strings.NewReader for JSON request bodies
+- Decode responses with json.NewDecoder(resp.Body).Decode(&body)
+- Unique descriptive data, NOT generic "test" strings
+- Format IDs with fmt.Sprintf("%.0f", id) when building URLs from float64