Merge engineer/hatch-replay into cto/ELF-15-hatch-stack-migration

Integrate the full Hatch v0.1 product (capture, inspect, SSE, mock, replay,
SQLite store, E2E smoke test) with the migration branch's docs/license
realignment (Apache-2.0 LICENSE, ADR-0002, clean README layout).

This produces a single launch-ready HEAD where the three Show HN demo bullets
are true and the repo carries an Apache-2.0 license.

Conflict resolution:
- cmd/hatch/main.go, cmd/hatch/main_test.go, go.mod: took replay (integrated
  chi router + handler routes + deps). Migration's foundation-only main.go
  and dep-less go.mod are superseded.
- .gitignore: took replay (narrowed /hatch to avoid matching cmd/hatch/).
- README.md: took migration (clean Repository Layout, Apache-2.0 license
  section). Replay's stale "Proprietary — All rights reserved" + apps/packages
  layout dropped.
- go.sum: auto-merged.
- brand/, internal/, docs/adrs/0002: brought in from replay / migration as
  non-conflicting additions.

Verified on merged HEAD:
- go test ./... — all pass
- go test ./cmd/hatch -run TestSmokeE2E — all 7 phases pass
- docker compose up --build — container runs; healthz/capture/inspect/mock
  all 200; mock returns configured status + body + content-type

CTO engineering sign-off for ELF-57: GO on this HEAD.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

.gitignore

@@ -8,16 +8,9 @@
 *.out
 go.work
 
-# Build artifacts
+# Build
 /bin
 /dist
-/hatch
-/hatch-*
-bin/
-*.db
-*.db-journal
-*.db-wal
-*.db-shm
 
 # IDE
 .idea/
@@ -26,3 +19,5 @@ bin/
 *.swo
 *~
 .DS_Store
+/hatch
+hatch.exe

brand/mark/mark-dark.svg

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000" width="1000" height="1000" role="img" aria-label="Hatch mark">
+  
+  <g>
+    <!-- Rounded square body -->
+    <rect x="100" y="100" width="800" height="800" rx="192" ry="192"
+          fill="none" stroke="#FAFAF9" stroke-width="88" stroke-linejoin="round"/>
+    <!-- The slot: a horizontal bar -->
+    <line x1="276" y1="460" x2="596" y2="460"
+          stroke="#FAFAF9" stroke-width="61.599999999999994" stroke-linecap="round"/>
+    <!-- The request: a small filled square above the slot -->
+    <rect x="436" y="244" width="128" height="128" fill="#FAFAF9"/>
+    <!-- The stem connecting the request to the slot -->
+    <line x1="500" y1="372" x2="500" y2="460"
+          stroke="#FAFAF9" stroke-width="46.199999999999996" stroke-linecap="round"/>
+  </g>
+</svg>

brand/mark/mark-on-dark.svg

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000" width="1000" height="1000" role="img" aria-label="Hatch mark">
+  <rect width="1000" height="1000" fill="#0A0A0B"/>
+  <g>
+    <!-- Rounded square body -->
+    <rect x="100" y="100" width="800" height="800" rx="192" ry="192"
+          fill="none" stroke="#FAFAF9" stroke-width="88" stroke-linejoin="round"/>
+    <!-- The slot: a horizontal bar -->
+    <line x1="276" y1="460" x2="596" y2="460"
+          stroke="#FAFAF9" stroke-width="61.599999999999994" stroke-linecap="round"/>
+    <!-- The request: a small filled square above the slot -->
+    <rect x="436" y="244" width="128" height="128" fill="#FAFAF9"/>
+    <!-- The stem connecting the request to the slot -->
+    <line x1="500" y1="372" x2="500" y2="460"
+          stroke="#FAFAF9" stroke-width="46.199999999999996" stroke-linecap="round"/>
+  </g>
+</svg>

brand/mark/mark-on-light.svg

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000" width="1000" height="1000" role="img" aria-label="Hatch mark">
+  <rect width="1000" height="1000" fill="#FAFAF9"/>
+  <g>
+    <!-- Rounded square body -->
+    <rect x="100" y="100" width="800" height="800" rx="192" ry="192"
+          fill="none" stroke="#0A0A0B" stroke-width="88" stroke-linejoin="round"/>
+    <!-- The slot: a horizontal bar -->
+    <line x1="276" y1="460" x2="596" y2="460"
+          stroke="#0A0A0B" stroke-width="61.599999999999994" stroke-linecap="round"/>
+    <!-- The request: a small filled square above the slot -->
+    <rect x="436" y="244" width="128" height="128" fill="#0A0A0B"/>
+    <!-- The stem connecting the request to the slot -->
+    <line x1="500" y1="372" x2="500" y2="460"
+          stroke="#0A0A0B" stroke-width="46.199999999999996" stroke-linecap="round"/>
+  </g>
+</svg>

brand/mark/mark.svg

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000" width="1000" height="1000" role="img" aria-label="Hatch mark">
+  
+  <g>
+    <!-- Rounded square body -->
+    <rect x="100" y="100" width="800" height="800" rx="192" ry="192"
+          fill="none" stroke="#0A0A0B" stroke-width="88" stroke-linejoin="round"/>
+    <!-- The slot: a horizontal bar -->
+    <line x1="276" y1="460" x2="596" y2="460"
+          stroke="#0A0A0B" stroke-width="61.599999999999994" stroke-linecap="round"/>
+    <!-- The request: a small filled square above the slot -->
+    <rect x="436" y="244" width="128" height="128" fill="#0A0A0B"/>
+    <!-- The stem connecting the request to the slot -->
+    <line x1="500" y1="372" x2="500" y2="460"
+          stroke="#0A0A0B" stroke-width="46.199999999999996" stroke-linecap="round"/>
+  </g>
+</svg>

cmd/hatch/main.go

@@ -1,8 +1,3 @@
-// Command hatch is the Hatch HTTP request inspector + mocker server.
-//
-// Hatch captures, inspects, and mocks HTTP requests. It ships as a single
-// static binary — one command on a VPS and your payloads never leave your
-// network.
 package main
 
 import (
@@ -10,6 +5,10 @@ import (
 	"log"
 	"net/http"
 	"os"
+
+	"github.com/elfoundation/hatch/internal/handler"
+	"github.com/elfoundation/hatch/internal/store"
+	"github.com/go-chi/chi/v5"
 )
 
 func main() {
@@ -17,20 +16,20 @@ func main() {
 	if port == "" {
 		port = "8080"
 	}
+	dbPath := os.Getenv("HATCH_DB_PATH")
+	repo, err := store.Open(dbPath)
+	if err != nil {
+		log.Fatalf("hatch: open store: %v", err)
+	}
+	defer repo.Close()
 
-	mux := http.NewServeMux()
-	mux.HandleFunc("GET /healthz", healthz)
+	h := handler.New(repo)
+	r := chi.NewRouter()
+	h.RegisterRoutes(r)
 
 	addr := fmt.Sprintf(":%s", port)
 	log.Printf("hatch starting on %s", addr)
-	if err := http.ListenAndServe(addr, mux); err != nil {
+	if err := http.ListenAndServe(addr, r); err != nil {
 		log.Fatalf("hatch server error: %v", err)
 	}
 }
-
-// healthz returns 200 OK with body "ok" for liveness probes.
-func healthz(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("Content-Type", "text/plain")
-	w.WriteHeader(http.StatusOK)
-	fmt.Fprintln(w, "ok")
-}

cmd/hatch/main_test.go

@@ -1,39 +1,63 @@
 package main
 
 import (
+	"context"
+	"encoding/json"
+	"fmt"
 	"io"
 	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
+	"time"
+
+	"github.com/elfoundation/hatch/internal/handler"
+	"github.com/elfoundation/hatch/internal/store"
+	"github.com/go-chi/chi/v5"
 )
 
-func TestHealthz(t *testing.T) {
+func TestHealthzViaRouter(t *testing.T) {
+	repo, err := store.Open(":memory:")
+	if err != nil {
+		t.Fatalf("open store: %v", err)
+	}
+	defer repo.Close()
+
+	r := chi.NewRouter()
+	h := handler.New(repo)
+	h.RegisterRoutes(r)
+
 	req := httptest.NewRequest(http.MethodGet, "/healthz", nil)
 	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
 
-	healthz(w, req)
-
-	resp := w.Result()
-	if resp.StatusCode != http.StatusOK {
-		t.Fatalf("expected 200 OK, got %d", resp.StatusCode)
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200 OK, got %d", w.Code)
 	}
-
-	body, err := io.ReadAll(resp.Body)
-	resp.Body.Close()
-	if err != nil {
-		t.Fatalf("failed to read response body: %v", err)
-	}
-
+	body, _ := io.ReadAll(w.Result().Body)
+	w.Result().Body.Close()
 	got := strings.TrimSpace(string(body))
 	if got != "ok" {
-		t.Fatalf("expected body 'ok', got '%s'", got)
+		t.Fatalf("expected body 'ok', got %q", got)
 	}
 }
 
 func TestHealthzSmoke(t *testing.T) {
-	// Smoke test: boot the server on a random port, hit /healthz, verify 200 + "ok".
-	srv := httptest.NewServer(http.HandlerFunc(healthz))
+	// Smoke: boot server on random port, hit /healthz.
+	// Use :memory: store so no filesystem dependency.
+	t.Setenv("HATCH_DB_PATH", ":memory:")
+
+	repo, err := store.Open(":memory:")
+	if err != nil {
+		t.Fatalf("open store: %v", err)
+	}
+	defer repo.Close()
+
+	r := chi.NewRouter()
+	h := handler.New(repo)
+	h.RegisterRoutes(r)
+
+	srv := httptest.NewServer(r)
 	defer srv.Close()
 
 	resp, err := http.Get(srv.URL + "/healthz")
@@ -45,14 +69,388 @@ func TestHealthzSmoke(t *testing.T) {
 	if resp.StatusCode != http.StatusOK {
 		t.Fatalf("expected 200 OK, got %d", resp.StatusCode)
 	}
-
 	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatalf("failed to read response body: %v", err)
 	}
-
 	got := strings.TrimSpace(string(body))
 	if got != "ok" {
-		t.Fatalf("expected body 'ok', got '%s'", got)
+		t.Fatalf("expected body 'ok', got %q", got)
 	}
 }
+
+// TestSmokeE2E is the acceptance gate: one command to prove the whole product works.
+// It starts a real server, exercises every feature (capture, inspect, SSE, mock,
+// replay), and verifies the full flow end-to-end.
+//
+// Run: go test ./cmd/hatch -run TestSmokeE2E -v
+func TestSmokeE2E(t *testing.T) {
+	// ---- Phase 0: Start server ----
+	repo, err := store.Open(":memory:")
+	if err != nil {
+		t.Fatalf("open store: %v", err)
+	}
+	defer repo.Close()
+
+	r := chi.NewRouter()
+	h := handler.New(repo)
+	h.RegisterRoutes(r)
+
+	srv := httptest.NewServer(r)
+	defer srv.Close()
+
+	client := &http.Client{Timeout: 10 * time.Second}
+
+	// ---- Phase 1: Health check ----
+	t.Run("healthz", func(t *testing.T) {
+		resp, err := client.Get(srv.URL + "/healthz")
+		if err != nil {
+			t.Fatalf("GET /healthz: %v", err)
+		}
+		defer resp.Body.Close()
+		if resp.StatusCode != http.StatusOK {
+			t.Fatalf("expected 200, got %d", resp.StatusCode)
+		}
+		body, _ := io.ReadAll(resp.Body)
+		if strings.TrimSpace(string(body)) != "ok" {
+			t.Fatalf("expected 'ok', got %q", string(body))
+		}
+	})
+
+	// ---- Phase 2: Capture requests (all HTTP methods) ----
+	t.Run("capture", func(t *testing.T) {
+		methods := []struct {
+			method string
+			body   string
+		}{
+			{"GET", ""},
+			{"POST", `{"order":"latte"}`},
+			{"PUT", `{"status":"updated"}`},
+			{"PATCH", `{"field":"partial"}`},
+			{"DELETE", ""},
+		}
+		for _, m := range methods {
+			var body io.Reader
+			if m.body != "" {
+				body = strings.NewReader(m.body)
+			}
+			req, _ := http.NewRequest(m.method, srv.URL+"/capture-test", body)
+			if m.body != "" {
+				req.Header.Set("Content-Type", "application/json")
+			}
+			req.Header.Set("X-Custom", "smoke-"+m.method)
+
+			resp, err := client.Do(req)
+			if err != nil {
+				t.Fatalf("%s /capture-test: %v", m.method, err)
+			}
+			resp.Body.Close()
+			if resp.StatusCode != http.StatusOK {
+				t.Fatalf("%s: expected 200, got %d", m.method, resp.StatusCode)
+			}
+		}
+
+		// Verify all 5 requests are in the store.
+		reqs, err := repo.ListRequests(context.Background(), "capture-test", 10)
+		if err != nil {
+			t.Fatalf("list requests: %v", err)
+		}
+		if len(reqs) != 5 {
+			t.Fatalf("expected 5 captured requests, got %d", len(reqs))
+		}
+	})
+
+	// ---- Phase 3: Inspect page (HTML rendering) ----
+	t.Run("inspect", func(t *testing.T) {
+		resp, err := client.Get(srv.URL + "/e/capture-test")
+		if err != nil {
+			t.Fatalf("GET /e/capture-test: %v", err)
+		}
+		defer resp.Body.Close()
+		if resp.StatusCode != http.StatusOK {
+			t.Fatalf("expected 200, got %d", resp.StatusCode)
+		}
+		ct := resp.Header.Get("Content-Type")
+		if !strings.Contains(ct, "text/html") {
+			t.Fatalf("expected text/html, got %q", ct)
+		}
+
+		body, _ := io.ReadAll(resp.Body)
+		html := string(body)
+
+		// Page structure.
+		if !strings.Contains(html, "<!DOCTYPE html>") {
+			t.Error("missing doctype")
+		}
+		if !strings.Contains(html, "capture-test") {
+			t.Error("missing endpoint ID")
+		}
+
+		// Request cards.
+		if !strings.Contains(html, "DELETE") {
+			t.Error("missing DELETE method badge")
+		}
+		if !strings.Contains(html, "POST") {
+			t.Error("missing POST method badge")
+		}
+
+		// Replay UI.
+		if !strings.Contains(html, "Replay") {
+			t.Error("missing Replay button")
+		}
+
+		// SSE live-update script.
+		if !strings.Contains(html, "EventSource") {
+			t.Error("missing EventSource script")
+		}
+
+		// Empty-state endpoint should show the hint.
+		resp2, err := client.Get(srv.URL + "/e/nonexistent")
+		if err != nil {
+			t.Fatalf("GET /e/nonexistent: %v", err)
+		}
+		defer resp2.Body.Close()
+		body2, _ := io.ReadAll(resp2.Body)
+		if !strings.Contains(string(body2), "Waiting for requests") {
+			t.Error("missing empty state for unused endpoint")
+		}
+	})
+
+	// ---- Phase 4: SSE stream receives live events ----
+	t.Run("sse", func(t *testing.T) {
+		// Use separate transports to avoid connection-pool issues with the long-lived SSE connection.
+		sseClient := &http.Client{
+			Transport: &http.Transport{DisableKeepAlives: true},
+			Timeout:   5 * time.Second,
+		}
+		captureClient := &http.Client{
+			Transport: &http.Transport{DisableKeepAlives: true},
+			Timeout:   5 * time.Second,
+		}
+
+		// Subscribe to SSE.
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+
+		sseReq, _ := http.NewRequestWithContext(ctx, http.MethodGet, srv.URL+"/e/sse-ep/events", nil)
+		sseResp, err := sseClient.Do(sseReq)
+		if err != nil {
+			t.Fatalf("SSE request: %v", err)
+		}
+		defer sseResp.Body.Close()
+
+		if sseResp.StatusCode != http.StatusOK {
+			t.Fatalf("SSE returned %d", sseResp.StatusCode)
+		}
+		ct := sseResp.Header.Get("Content-Type")
+		if !strings.HasPrefix(ct, "text/event-stream") {
+			t.Fatalf("SSE Content-Type: %q", ct)
+		}
+
+		// Capture a request on a goroutine; read SSE on main.
+		eventCh := make(chan string, 1)
+		go func() {
+			buf := make([]byte, 4096)
+			n, _ := sseResp.Body.Read(buf)
+			eventCh <- string(buf[:n])
+		}()
+
+		time.Sleep(20 * time.Millisecond) // let SSE subscription register
+
+		resp, err := captureClient.Post(srv.URL+"/sse-ep", "application/json", strings.NewReader(`{"sse":true}`))
+		if err != nil {
+			t.Fatalf("capture: %v", err)
+		}
+		resp.Body.Close()
+
+		select {
+		case event := <-eventCh:
+			if !strings.Contains(event, "data:") {
+				t.Fatalf("SSE event missing 'data:' prefix: %q", event)
+			}
+			// Body value is JSON-escaped in the SSE stream (e.g. "body":"{\"sse\":true}").
+			// Check for the content values rather than the exact escaped form.
+			if !strings.Contains(event, `sse`) || !strings.Contains(event, `true`) {
+				t.Fatalf("SSE event missing body content: %q", event)
+			}
+		case <-time.After(2 * time.Second):
+			t.Fatal("timeout waiting for SSE event")
+		}
+	})
+
+	// ---- Phase 5: Mock configuration and response ----
+	t.Run("mock", func(t *testing.T) {
+		// Set a mock on a fresh endpoint.
+		mockBody := `{"status":418,"headers":{"X-Teapot":"true"},"body":"eyJicmV3aW5nIjp0cnVlfQ=="}`
+
+		resp, err := client.Post(
+			srv.URL+"/e/mock-ep/mock",
+			"application/json",
+			strings.NewReader(mockBody),
+		)
+		if err != nil {
+			t.Fatalf("PUT /e/mock-ep/mock: %v", err)
+		}
+		resp.Body.Close()
+		if resp.StatusCode != http.StatusOK {
+			// PUT is registered as PUT, but we use POST here — let's use PUT.
+			// The route is PUT /e/{endpointID}/mock
+		}
+
+		// Use proper PUT method.
+		req, _ := http.NewRequest(http.MethodPut, srv.URL+"/e/mock-ep-2/mock", strings.NewReader(mockBody))
+		req.Header.Set("Content-Type", "application/json")
+		resp2, err := client.Do(req)
+		if err != nil {
+			t.Fatalf("PUT /e/mock-ep-2/mock: %v", err)
+		}
+		resp2.Body.Close()
+		if resp2.StatusCode != http.StatusOK {
+			t.Fatalf("expected 200 OK from mock set, got %d: %s", resp2.StatusCode, readBody(resp2))
+		}
+
+		// Verify mock is stored.
+		mock, err := repo.GetMock(context.Background(), "mock-ep-2")
+		if err != nil {
+			t.Fatalf("mock not stored: %v", err)
+		}
+		if mock.Status != 418 {
+			t.Errorf("expected status 418, got %d", mock.Status)
+		}
+		if mock.Headers["X-Teapot"] != "true" {
+			t.Errorf("expected X-Teapot header, got %v", mock.Headers)
+		}
+
+		// Capture a request — should return the mock response.
+		resp3, err := client.Post(srv.URL+"/mock-ep-2", "application/json", strings.NewReader(`{"order":"earl grey"}`))
+		if err != nil {
+			t.Fatalf("capture on mocked endpoint: %v", err)
+		}
+		defer resp3.Body.Close()
+		if resp3.StatusCode != 418 {
+			t.Fatalf("expected mock status 418, got %d", resp3.StatusCode)
+		}
+		if resp3.Header.Get("X-Teapot") != "true" {
+			t.Errorf("expected X-Teapot: true, got %q", resp3.Header.Get("X-Teapot"))
+		}
+		body, _ := io.ReadAll(resp3.Body)
+		// Body is base64-decoded by Go's json decoder ([]byte field).
+		if strings.TrimSpace(string(body)) != `{"brewing":true}` {
+			t.Errorf("expected mock body, got %q", string(body))
+		}
+	})
+
+	// ---- Phase 6: Replay ----
+	t.Run("replay", func(t *testing.T) {
+		// Start a sink server that echoes back what it receives.
+		sink := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("X-Sink", "yes")
+			w.WriteHeader(http.StatusCreated)
+			fmt.Fprintf(w, `{"echo":{"method":%q,"path":%q}}`, r.Method, r.URL.Path)
+		}))
+		defer sink.Close()
+
+		// Allow private replay so we can hit the loopback sink.
+		t.Setenv("HATCH_ALLOW_PRIVATE_REPLAY", "true")
+
+		// Capture a request to replay later.
+		captureResp, err := client.Post(srv.URL+"/replay-ep", "application/json", strings.NewReader(`{"msg":"replay me"}`))
+		if err != nil {
+			t.Fatalf("capture for replay: %v", err)
+		}
+		captureResp.Body.Close()
+
+		// Get the captured request ID from the store.
+		reqs, _ := repo.ListRequests(context.Background(), "replay-ep", 1)
+		if len(reqs) != 1 {
+			t.Fatalf("expected 1 captured request, got %d", len(reqs))
+		}
+		reqID := reqs[0].ID
+
+		// Replay to the sink.
+		replayPayload := fmt.Sprintf(`{"target_url":%q}`, sink.URL)
+		replayResp, err := client.Post(
+			srv.URL+"/e/replay-ep/requests/"+reqID+"/replay",
+			"application/json",
+			strings.NewReader(replayPayload),
+		)
+		if err != nil {
+			t.Fatalf("replay request: %v", err)
+		}
+		defer replayResp.Body.Close()
+		if replayResp.StatusCode != http.StatusOK {
+			body, _ := io.ReadAll(replayResp.Body)
+			t.Fatalf("replay returned %d: %s", replayResp.StatusCode, string(body))
+		}
+
+		var result struct {
+			Status  int               `json:"status"`
+			Headers map[string]string `json:"headers"`
+			Body    string            `json:"body"`
+		}
+		json.NewDecoder(replayResp.Body).Decode(&result)
+		if result.Status != 201 {
+			t.Errorf("expected replay sink status 201, got %d", result.Status)
+		}
+		if result.Headers["X-Sink"] != "yes" {
+			t.Errorf("expected X-Sink: yes, got %q", result.Headers["X-Sink"])
+		}
+	})
+
+	// ---- Phase 7: Edge cases ----
+	t.Run("edge", func(t *testing.T) {
+		// Capture with query params.
+		resp, err := client.Get(srv.URL + "/query-ep?foo=bar&baz=qux")
+		if err != nil {
+			t.Fatalf("capture with query: %v", err)
+		}
+		resp.Body.Close()
+
+		reqs, _ := repo.ListRequests(context.Background(), "query-ep", 1)
+		if len(reqs) != 1 {
+			t.Fatalf("expected 1 request, got %d", len(reqs))
+		}
+		if reqs[0].Query != "foo=bar&baz=qux" {
+			t.Errorf("expected query 'foo=bar&baz=qux', got %q", reqs[0].Query)
+		}
+
+		// Capture with binary body.
+		binaryBody := []byte{0x00, 0x01, 0x02, 0xFF, 0xFE}
+		resp2, err := client.Post(srv.URL+"/binary-ep", "application/octet-stream", strings.NewReader(string(binaryBody)))
+		if err != nil {
+			t.Fatalf("binary capture: %v", err)
+		}
+		resp2.Body.Close()
+
+		reqs2, _ := repo.ListRequests(context.Background(), "binary-ep", 1)
+		if len(reqs2) != 1 {
+			t.Fatalf("expected 1 binary request, got %d", len(reqs2))
+		}
+		if len(reqs2[0].Body) != len(binaryBody) {
+			t.Errorf("expected body len %d, got %d", len(binaryBody), len(reqs2[0].Body))
+		}
+
+		// SSRF protection: replay to localhost is denied.
+		replayPayload := `{"target_url":"http://localhost:9999/"}`
+		req, _ := http.NewRequest(http.MethodPost, srv.URL+"/e/query-ep/requests/"+reqs[0].ID+"/replay", strings.NewReader(replayPayload))
+		req.Header.Set("Content-Type", "application/json")
+		resp3, err := client.Do(req)
+		if err != nil {
+			t.Fatalf("SSRF test: %v", err)
+		}
+		resp3.Body.Close()
+		if resp3.StatusCode != http.StatusForbidden {
+			t.Errorf("expected 403 for localhost replay, got %d", resp3.StatusCode)
+		}
+	})
+
+	t.Log("E2E smoke test complete — all phases passed")
+}
+
+func readBody(resp *http.Response) string {
+	if resp.Body == nil {
+		return ""
+	}
+	b, _ := io.ReadAll(resp.Body)
+	return string(b)
+}

docs/brand/usage.md

@@ -0,0 +1,142 @@
+# Hatch brand usage
+
+> One-pager. Read this before you put the wordmark anywhere.
+
+## Files in this kit
+
+```
+brand/
+├── wordmark/
+│   ├── wordmark.svg              # master wordmark (text-only, with embedded font)
+│   ├── wordmark-dark.svg         # dark variant (paper on transparent)
+│   ├── wordmark-on-light.svg     # paper-on-warm-white background
+│   ├── wordmark-on-dark.svg      # paper-on-ink background
+│   └── wordmark-*.png            # 200x60, 400x120, 800x240, 1200x360
+├── mark/
+│   ├── mark.svg                  # the icon alone (no text)
+│   ├── mark-on-light.svg
+│   ├── mark-on-dark.svg
+│   └── mark-{16,32,48,64,128,192,256,512,1024}.png
+├── favicon/
+│   ├── favicon.ico               # 16+32+48 multi-size ico
+│   └── favicon-{16,32,48,192,512}.png
+├── banner/
+│   ├── readme-banner.png         # 1280x640
+│   └── readme-banner@2x.png      # 2560x1280
+└── og/
+    ├── og.png                    # 1200x630
+    └── og@2x.png                 # 2400x1260
+```
+
+## What goes where
+
+| Surface                                  | Use                              | File                                   |
+| ---------------------------------------- | -------------------------------- | -------------------------------------- |
+| Favicon (browser tab, GitHub avatar)     | The **mark**, not the wordmark   | `brand/favicon/favicon.ico`            |
+| Apple touch icon / PWA icon               | The mark, 512px                  | `brand/favicon/favicon-512.png`        |
+| README header                            | The **wordmark** (200x60+)       | `brand/wordmark/wordmark-200x60.png`   |
+| GitHub social preview / blog / link card | The **OG image** (1200x630)      | `brand/og/og.png`                      |
+| Big surfaces, slides, README top         | The **README banner** (1280x640) | `brand/banner/readme-banner.png`       |
+
+For the favicon, always use `mark.svg` or one of the favicon PNGs — never the full
+wordmark. The wordmark does not read at 16x16.
+
+## Clear space
+
+Treat the mark as a square and the wordmark as the mark + the word. Clear space
+is **1× the cap-height of the "h" in "hatch"** on every side.
+
+- Wordmark: at least one "h"-height of empty space on top, bottom, left, and right
+- Mark: at least one "h"-height on every side
+
+```
+   ┌──────────────────────────────┐
+   │                              │  ← 1× clear space
+   │   ┌──┐  hatch                │
+   │   │  │                       │
+   │   └──┘                       │
+   │                              │  ← 1× clear space
+   └──────────────────────────────┘
+```
+
+## Minimum size
+
+- Wordmark: **120px wide** is the minimum. Below that, switch to the mark.
+- Mark: **16px** is the minimum (we ship a tuned 16px favicon).
+
+## Color
+
+The brand has **one active color, one neutral, and one accent**. That's it.
+
+| Token    | Hex       | Use                                               |
+| -------- | --------- | ------------------------------------------------- |
+| Ink      | `#0A0A0B` | Wordmark, primary type, dark surfaces             |
+| Paper    | `#FAFAF9` | Light surfaces, type on dark                      |
+| Accent   | `#F59E0B` | The "captured" signal — one place per composition |
+
+Neutral scale (for docs and UIs, not the wordmark): `#71717A` `#A1A1AA` `#D4D4D8` `#E4E4E7` `#F4F4F5`.
+
+**Don't pick colors outside the kit.** If you need another color, ask the Head of
+Marketing; do not invent one.
+
+## Light and dark mode
+
+The wordmark and the mark are **single-color**. Pick the right variant for the
+surface — never change the color of the wordmark to fit a theme.
+
+- **On a light surface** (≥ 4.5:1 contrast): use `wordmark.svg` (ink) or `mark.svg`
+- **On a dark surface**: use `wordmark-dark.svg` (paper) or `mark-dark.svg`
+- **Need a background tile?** Use `wordmark-on-light.svg` or `wordmark-on-dark.svg`
+
+For GitHub READMEs, GitHub auto-switches images in dark mode only if you use
+the `#gh-dark-mode-only` / `#gh-light-mode-only` MediaFragments trick:
+
+```markdown
+<picture>
+  <source media="(prefers-color-scheme: dark)" srcset="brand/wordmark/wordmark-dark.svg">
+  <img src="brand/wordmark/wordmark.svg" alt="Hatch" width="200">
+</picture>
+```
+
+## Typography (display + body)
+
+The wordmark uses **Inter Bold**. The brand voice guide and READMEs use:
+
+- **Display / headings:** Inter (Bold or SemiBold)
+- **Code / mono:** JetBrains Mono (Regular or Medium)
+
+Both are OFL-licensed and on the system. Don't substitute a different sans or mono
+in brand surfaces without sign-off.
+
+## Do not
+
+- **Don't stretch.** Always use the mark/wordmark at its native aspect ratio. If
+  you need it bigger, scale proportionally.
+- **Don't recolor.** The wordmark is ink or paper — period. No brand-color,
+  gradient, rainbow, or AI-painted versions.
+- **Don't add effects.** No drop shadows, no glows, no outlines, no bevel, no
+  inner shadows. The mark is a flat shape.
+- **Don't rotate.** The hatch opens at the top. Don't tilt the mark.
+- **Don't rearrange the wordmark.** The mark always sits to the **left** of the
+  wordmark, with a 0.22×-mark-width gap. No stacking, no right-alignment.
+- **Don't put the wordmark on a busy image.** The wordmark needs contrast. On a
+  photo or a complex background, use a solid color tile behind it.
+- **Don't use the wordmark in body copy.** The wordmark is for headers, banners,
+  and brand surfaces only. Body type stays in Inter.
+- **Don't use the favicon as a profile picture.** Use the 512px PNG (`mark-512.png`)
+  for that, and round the corners if you want — but the square mark is the
+  canonical shape.
+
+## Licensing & attribution
+
+- **Inter** — SIL Open Font License 1.1 (Inter by Rasmus Andersson, rsms.me)
+- **JetBrains Mono** — SIL Open Font License 1.1 (JetBrains)
+- The mark and wordmark are the property of El Foundation. Use them to talk about
+  Hatch. Do not register them as a trademark or use them to sell a competing
+  product.
+
+## Need something new?
+
+If a new surface needs a brand asset that isn't in the kit (a slide template, a
+business card, a T-shirt, an icon variant), open an issue assigned to the Brand
+Designer. Do not stretch, recolor, or rearrange this kit to make it work.

go.mod

@@ -1,3 +1,20 @@
 module github.com/elfoundation/hatch
 
 go 1.25.0
+
+require (
+	github.com/go-chi/chi/v5 v5.3.0
+	github.com/google/uuid v1.6.0
+	modernc.org/sqlite v1.53.0
+)
+
+require (
+	github.com/dustin/go-humanize v1.0.1 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/ncruces/go-strftime v1.0.0 // indirect
+	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
+	golang.org/x/sys v0.44.0 // indirect
+	modernc.org/libc v1.73.4 // indirect
+	modernc.org/mathutil v1.7.1 // indirect
+	modernc.org/memory v1.11.0 // indirect
+)

go.sum

@@ -0,0 +1,53 @@
+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 v5.3.0 h1:halUjDxhshgXHMrao5bB8eNBXo/rnzwr8m5m36glehM=
+github.com/go-chi/chi/v5 v5.3.0/go.mod h1:R+tYY2hNuVUUjxoPtqUdgBqevM9s9njzkTLutVsOCto=
+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/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
+github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+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 v1.0.0 h1:HMFp8mLCTPp341M/ZnA4qaf7ZlsbTc+miZjCLOFAw7w=
+github.com/ncruces/go-strftime v1.0.0/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/mod v0.36.0 h1:JJjpVx6myfUsUdAzZuOSTTmRE0PfZeNWzzvKrP7amb4=
+golang.org/x/mod v0.36.0/go.mod h1:moc6ELqsWcOw5Ef3xVprK5ul/MvtVvkIXLziUOICjUQ=
+golang.org/x/sync v0.20.0 h1:e0PTpb7pjO8GAtTs2dQ6jYa5BWYlMuX047Dco/pItO4=
+golang.org/x/sync v0.20.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.44.0 h1:ildZl3J4uzeKP07r2F++Op7E9B29JRUy+a27EibtBTQ=
+golang.org/x/sys v0.44.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+golang.org/x/tools v0.45.0 h1:18qN3FAooORvApf5XjCXgsuayZOEtXf6JK18I3+ONa8=
+golang.org/x/tools v0.45.0/go.mod h1:LuUGqqaXcXMEFEruIVJVm5mgDD8vww/z/SR1gQ4uE/0=
+modernc.org/cc/v4 v4.28.4 h1:Hd/4Es+MBj+/7hSdZaisNyu6bv3V0Dp2MdllyfqaH+c=
+modernc.org/cc/v4 v4.28.4/go.mod h1:OnovgIhbbMXMu1aISnJ0wvVD1KnW+cAUJkIrAWh+kVI=
+modernc.org/ccgo/v4 v4.34.4 h1:OVnSOWQjVKOYkFxoHYB+qQmSHK5gqMqARM+K9DpR/Ws=
+modernc.org/ccgo/v4 v4.34.4/go.mod h1:qdKqE8FNIYyysougB1RX9MxCzp5oJOcQXSobANJ4TuE=
+modernc.org/fileutil v1.4.0 h1:j6ZzNTftVS054gi281TyLjHPp6CPHr2KCxEXjEbD6SM=
+modernc.org/fileutil v1.4.0/go.mod h1:EqdKFDxiByqxLk8ozOxObDSfcVOv/54xDs/DUHdvCUU=
+modernc.org/gc/v2 v2.6.5 h1:nyqdV8q46KvTpZlsw66kWqwXRHdjIlJOhG6kxiV/9xI=
+modernc.org/gc/v2 v2.6.5/go.mod h1:YgIahr1ypgfe7chRuJi2gD7DBQiKSLMPgBQe9oIiito=
+modernc.org/gc/v3 v3.1.3 h1:6QAplYyVO+KdPW3pGnqmJDUxtkec8ooEWvks/hhU3lc=
+modernc.org/gc/v3 v3.1.3/go.mod h1:HFK/6AGESC7Ex+EZJhJ2Gni6cTaYpSMmU/cT9RmlfYY=
+modernc.org/goabi0 v0.2.0 h1:HvEowk7LxcPd0eq6mVOAEMai46V+i7Jrj13t4AzuNks=
+modernc.org/goabi0 v0.2.0/go.mod h1:CEFRnnJhKvWT1c1JTI3Avm+tgOWbkOu5oPA8eH8LnMI=
+modernc.org/libc v1.73.4 h1:+ra4Ui8ngyt8HDcO1FTDPWlkAh6yOdaO2yAoh8MddQA=
+modernc.org/libc v1.73.4/go.mod h1:DXZ3eO8qMCNn2SnmTNCiC71nJ9Rcq3PsnpU6Vc4rWK8=
+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 v0.2.0 h1:tGyef5ApycA7FSEOMraay9SaTk5zmbx7Tu+cJs4QKZg=
+modernc.org/opt v0.2.0/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 v1.53.0 h1:20WG8N9q4ji/dEqGk4uiI0c6OPjSeLTNYGFCc3+7c1M=
+modernc.org/sqlite v1.53.0/go.mod h1:xoEpOIpGrgT48H5iiyt/YXPCZPEzlfmfFwtk8Lklw8s=
+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=

internal/handler/handler.go

@@ -0,0 +1,125 @@
+package handler
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"strings"
+
+	"github.com/elfoundation/hatch/internal/store"
+	"github.com/go-chi/chi/v5"
+	"github.com/go-chi/chi/v5/middleware"
+)
+
+// Handler groups all HTTP handlers and their shared dependencies.
+type Handler struct {
+	Repo store.Repository
+}
+
+// New creates a new Handler with the given store.
+func New(repo store.Repository) *Handler {
+	return &Handler{Repo: repo}
+}
+
+// RegisterRoutes mounts all routes on the given chi router.
+func (h *Handler) RegisterRoutes(r chi.Router) {
+	r.Use(middleware.Logger)
+	r.Use(middleware.Recoverer)
+
+	// Health check.
+	r.Get("/healthz", Healthz)
+
+	// Inspect page: server-rendered request list.
+	r.Get("/e/{endpointID}", HandleInspect(h.Repo))
+
+	// SSE stream for live updates.
+	r.Get("/e/{endpointID}/events", HandleSSE(h.Repo))
+
+	// Mock configuration.
+	r.Put("/e/{endpointID}/mock", HandleMock(h.Repo))
+
+	// Replay: one-click re-send of a captured request.
+	r.Post("/e/{endpointID}/requests/{requestID}/replay", HandleReplay(h.Repo))
+
+	// Capture webhook: any method on /{endpointID} (wildcard, must be last).
+	r.HandleFunc("/{endpointID}", h.capture)
+	r.HandleFunc("/{endpointID}/*", h.capture)
+}
+
+// capture handles incoming webhook captures on /{endpointID}.
+func (h *Handler) capture(w http.ResponseWriter, r *http.Request) {
+	eid := r.PathValue("endpointID")
+	if eid == "" {
+		writeError(w, http.StatusBadRequest, "missing endpoint ID")
+		return
+	}
+
+	ctx := r.Context()
+
+	// Auto-create endpoint if it doesn't exist.
+	if _, err := h.Repo.GetEndpoint(ctx, eid); err != nil {
+		h.Repo.CreateEndpoint(ctx, eid)
+	}
+
+	// Collect headers as JSON.
+	hdr := map[string]string{}
+	for k, v := range r.Header {
+		hdr[k] = strings.Join(v, ", ")
+	}
+	hdrJSON, _ := json.Marshal(hdr)
+
+	// Read body.
+	var body []byte
+	if r.Body != nil {
+		body, _ = io.ReadAll(r.Body)
+		r.Body.Close()
+	}
+
+	// Store the request.
+	req := &store.Request{
+		Method:  r.Method,
+		Path:    r.URL.Path,
+		Headers: string(hdrJSON),
+		Query:   r.URL.RawQuery,
+		Body:    body,
+	}
+	if err := h.Repo.AppendRequest(ctx, eid, req); err != nil {
+		writeError(w, http.StatusInternalServerError, "failed to store request")
+		return
+	}
+
+	// Broadcast via SSE.
+	broadcastRequest(eid, req)
+
+	// Look up mock response for this endpoint.
+	mock, err := h.Repo.GetMock(ctx, eid)
+	if err == nil && mock != nil {
+		for k, v := range mock.Headers {
+			w.Header().Set(k, v)
+		}
+		w.WriteHeader(mock.Status)
+		if mock.Body != nil {
+			w.Write(mock.Body)
+		}
+		return
+	}
+
+	// Default: return 200 OK with empty JSON.
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	json.NewEncoder(w).Encode(map[string]interface{}{"ok": true})
+}
+
+// Healthz returns 200 OK for liveness probes.
+func Healthz(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/plain")
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte("ok\n"))
+}
+
+// writeError writes a JSON error response.
+func writeError(w http.ResponseWriter, status int, msg string) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	json.NewEncoder(w).Encode(map[string]string{"error": msg})
+}

internal/handler/handler_test.go

@@ -0,0 +1,442 @@
+package handler
+
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/elfoundation/hatch/internal/store"
+	"github.com/go-chi/chi/v5"
+)
+
+// fakeRepo implements store.Repository for tests.
+type fakeRepo struct {
+	endpoints map[string]*store.Endpoint
+	requests  []*store.Request
+	mocks     map[string]*store.MockConfig
+}
+
+func newFakeRepo() *fakeRepo {
+	return &fakeRepo{
+		endpoints: map[string]*store.Endpoint{},
+		mocks:     map[string]*store.MockConfig{},
+	}
+}
+
+func (f *fakeRepo) CreateEndpoint(_ context.Context, u string) (*store.Endpoint, error) {
+	e := &store.Endpoint{ID: u, URL: u, CreatedAt: "t", UpdatedAt: "t"}
+	f.endpoints[u] = e
+	return e, nil
+}
+func (f *fakeRepo) GetEndpoint(_ context.Context, id string) (*store.Endpoint, error) {
+	e, ok := f.endpoints[id]
+	if !ok {
+		return nil, errNotFound
+	}
+	return e, nil
+}
+func (f *fakeRepo) AppendRequest(_ context.Context, eid string, r *store.Request) error {
+	r.ID = "req-" + string(rune(len(f.requests)+'0'))
+	r.EndpointID = eid
+	f.requests = append(f.requests, r)
+	return nil
+}
+func (f *fakeRepo) GetRequest(_ context.Context, id string) (*store.Request, error) {
+	for _, r := range f.requests {
+		if r.ID == id {
+			return r, nil
+		}
+	}
+	return nil, errNotFound
+}
+func (f *fakeRepo) ListRequests(_ context.Context, _ string, _ int) ([]*store.Request, error) {
+	return f.requests, nil
+}
+func (f *fakeRepo) GetMock(_ context.Context, endpointID string) (*store.MockConfig, error) {
+	m, ok := f.mocks[endpointID]
+	if !ok {
+		return nil, errNotFound
+	}
+	return m, nil
+}
+func (f *fakeRepo) SetMock(_ context.Context, mock *store.MockConfig) error {
+	f.mocks[mock.EndpointID] = mock
+	return nil
+}
+func (f *fakeRepo) Close() error { return nil }
+
+var errNotFound = &se{"nf"}
+
+type se struct{ m string }
+
+func (e *se) Error() string { return e.m }
+
+// testRouter creates a chi router with all routes registered using a fake repo.
+func testRouter(repo store.Repository) chi.Router {
+	r := chi.NewRouter()
+	h := New(repo)
+	h.RegisterRoutes(r)
+	return r
+}
+
+func TestHealthz(t *testing.T) {
+	r := testRouter(newFakeRepo())
+	req := httptest.NewRequest(http.MethodGet, "/healthz", nil)
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	body := strings.TrimSpace(w.Body.String())
+	if body != "ok" {
+		t.Fatalf("expected 'ok', got %q", body)
+	}
+}
+
+func TestCaptureRecordsAllVerbs(t *testing.T) {
+	methods := []string{"GET", "POST", "PUT", "PATCH", "DELETE"}
+	for _, m := range methods {
+		repo := newFakeRepo()
+		r := testRouter(repo)
+
+		body := ""
+		if m == "POST" || m == "PUT" || m == "PATCH" {
+			body = `{"k":"v"}`
+		}
+		req := httptest.NewRequest(m, "/ep", strings.NewReader(body))
+		if m == "GET" {
+			req.Header.Set("Accept", "text/html")
+		}
+		w := httptest.NewRecorder()
+		r.ServeHTTP(w, req)
+
+		if w.Code != 200 {
+			t.Errorf("%s: expected 200, got %d", m, w.Code)
+		}
+		if len(repo.requests) != 1 {
+			t.Errorf("%s: expected 1 request, got %d", m, len(repo.requests))
+			continue
+		}
+		reqCaptured := repo.requests[0]
+		if reqCaptured.Method != m {
+			t.Errorf("%s: wrong method %s", m, reqCaptured.Method)
+		}
+	}
+}
+
+func TestSSEStreamReceivesEventOnCapture(t *testing.T) {
+	repo := newFakeRepo()
+	srv := httptest.NewServer(testRouter(repo))
+	defer srv.Close()
+
+	// Use separate clients with separate transports to avoid
+	// connection-pool contention with the long-lived SSE connection.
+	sseClient := &http.Client{
+		Transport: &http.Transport{DisableKeepAlives: true},
+	}
+	captureClient := &http.Client{
+		Transport: &http.Transport{DisableKeepAlives: true},
+	}
+
+	// Subscribe to SSE with a cancellable context.
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	sseReq, err := http.NewRequestWithContext(ctx, http.MethodGet, srv.URL+"/e/ep/events", nil)
+	if err != nil {
+		t.Fatalf("SSE request create failed: %v", err)
+	}
+	sseResp, err := sseClient.Do(sseReq)
+	if err != nil {
+		t.Fatalf("SSE GET failed: %v", err)
+	}
+	defer sseResp.Body.Close()
+
+	if sseResp.StatusCode != http.StatusOK {
+		t.Fatalf("SSE returned %d", sseResp.StatusCode)
+	}
+	ct := sseResp.Header.Get("Content-Type")
+	if !strings.HasPrefix(ct, "text/event-stream") {
+		t.Fatalf("SSE Content-Type is %q, expected text/event-stream", ct)
+	}
+
+	// Read SSE body in a goroutine; capture in main goroutine.
+	bodyCh := make(chan string, 1)
+	go func() {
+		buf := make([]byte, 4096)
+		n, _ := sseResp.Body.Read(buf)
+		bodyCh <- string(buf[:n])
+	}()
+
+	// Small sleep to let the SSE subscription register.
+	time.Sleep(10 * time.Millisecond)
+
+	// Capture a request on the same server.
+	captureResp, err := captureClient.Post(srv.URL+"/ep", "application/json", strings.NewReader(`{"msg":"hello"}`))
+	if err != nil {
+		t.Fatalf("capture POST failed: %v", err)
+	}
+	captureResp.Body.Close()
+	if captureResp.StatusCode != http.StatusOK {
+		t.Fatalf("capture returned %d", captureResp.StatusCode)
+	}
+
+	// Wait for the SSE event with a timeout.
+	select {
+	case body := <-bodyCh:
+		if !strings.Contains(body, "data:") {
+			t.Fatalf("SSE stream missing 'data:' prefix: %q", body)
+		}
+		if !strings.Contains(body, "\"method\":\"POST\"") {
+			t.Fatalf("SSE stream missing POST method: %q", body)
+		}
+	case <-time.After(2 * time.Second):
+		t.Fatal("timeout waiting for SSE event")
+	}
+
+	// Cancel context to close the SSE connection.
+	cancel()
+}
+
+func TestInspectReturnsHTML(t *testing.T) {
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "ep")
+	repo.AppendRequest(nil, "ep", &store.Request{
+		Method:  "POST",
+		Path:    "/ep/webhook",
+		Headers: `{"Content-Type":"application/json"}`,
+		Query:   "foo=bar",
+		Body:    []byte(`{"msg":"hello"}`),
+	})
+
+	r := testRouter(repo)
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, httptest.NewRequest("GET", "/e/ep", nil))
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	ct := w.Header().Get("Content-Type")
+	if !strings.Contains(ct, "text/html") {
+		t.Fatalf("expected text/html Content-Type, got %q", ct)
+	}
+
+	body := w.Body.String()
+
+	// Should contain the endpoint ID.
+	if !strings.Contains(body, "ep") {
+		t.Error("missing endpoint ID in HTML")
+	}
+
+	// Should contain the request method badge.
+	if !strings.Contains(body, "POST") {
+		t.Error("missing POST method in HTML")
+	}
+
+	// Should contain the request path.
+	if !strings.Contains(body, "/ep/webhook") {
+		t.Error("missing request path in HTML")
+	}
+
+	// Should contain the header JSON.
+	if !strings.Contains(body, "Content-Type") {
+		t.Error("missing Content-Type header in HTML")
+	}
+
+	// Should contain the query string.
+	if !strings.Contains(body, "foo=bar") {
+		t.Error("missing query string in HTML")
+	}
+
+	// Should contain the body content (html/template escapes quotes).
+	if !strings.Contains(body, "msg") || !strings.Contains(body, "hello") {
+		t.Error("missing request body content in HTML")
+	}
+
+	// Should contain the replay button.
+	if !strings.Contains(body, "Replay") {
+		t.Error("missing Replay button in HTML")
+	}
+
+	// Should contain SSE EventSource script.
+	if !strings.Contains(body, "EventSource") {
+		t.Error("missing EventSource in HTML")
+	}
+}
+
+func TestInspectEmptyState(t *testing.T) {
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "new-ep")
+
+	r := testRouter(repo)
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, httptest.NewRequest("GET", "/e/new-ep", nil))
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	body := w.Body.String()
+
+	// Should show the "waiting for requests" empty state.
+	if !strings.Contains(body, "Waiting for requests") {
+		t.Error("missing empty state message")
+	}
+
+	// Should show the usage hint with the endpoint ID.
+	if !strings.Contains(body, "/new-ep") {
+		t.Error("missing usage hint with endpoint ID")
+	}
+
+	// No request cards should be rendered.
+	if strings.Contains(body, `class="request"`) {
+		t.Error("unexpected request card in empty state")
+	}
+}
+
+func TestInspectAutoCreatesEndpoint(t *testing.T) {
+	repo := newFakeRepo()
+
+	// The endpoint doesn't exist yet.
+	r := testRouter(repo)
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, httptest.NewRequest("GET", "/e/auto-ep", nil))
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	// The endpoint should now exist in the repo.
+	ep, err := repo.GetEndpoint(nil, "auto-ep")
+	if err != nil {
+		t.Fatalf("endpoint was not auto-created: %v", err)
+	}
+	if ep.ID != "auto-ep" {
+		t.Errorf("expected endpoint ID 'auto-ep', got %q", ep.ID)
+	}
+
+	body := w.Body.String()
+	if !strings.Contains(body, "auto-ep") {
+		t.Error("missing endpoint ID in auto-created page")
+	}
+	if !strings.Contains(body, "Waiting for requests") {
+		t.Error("missing empty state for auto-created endpoint")
+	}
+}
+
+func TestCaptureReturnsJSON200(t *testing.T) {
+	r := testRouter(newFakeRepo())
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, httptest.NewRequest("GET", "/t", nil))
+
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	if !strings.Contains(w.Header().Get("Content-Type"), "application/json") {
+		t.Error("not json")
+	}
+	data, _ := io.ReadAll(w.Result().Body)
+	w.Result().Body.Close()
+	var v map[string]interface{}
+	if json.Unmarshal(data, &v) != nil {
+		t.Fatal("invalid json")
+	}
+}
+
+func TestMockSetsAndConfiguresResponse(t *testing.T) {
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "mock-ep")
+
+	r := testRouter(repo)
+
+	// Set a mock via PUT.
+	mockBody := `{"status": 201, "headers": {"X-Mocked": "yes"}, "body": "bW9ja2Vk"}`
+	req := httptest.NewRequest(http.MethodPut, "/e/mock-ep/mock", strings.NewReader(mockBody))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200 OK, got %d: %s", w.Code, w.Body.String())
+	}
+
+	// Verify the mock was stored.
+	mock, err := repo.GetMock(nil, "mock-ep")
+	if err != nil {
+		t.Fatalf("mock not stored: %v", err)
+	}
+	if mock.Status != 201 {
+		t.Errorf("expected status 201, got %d", mock.Status)
+	}
+	if mock.Headers["X-Mocked"] != "yes" {
+		t.Errorf("expected X-Mocked header, got %v", mock.Headers)
+	}
+}
+
+func TestMockReturnsConfiguredResponseOnCapture(t *testing.T) {
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "mock-cap")
+	// Pre-set a mock.
+	repo.SetMock(nil, &store.MockConfig{
+		EndpointID: "mock-cap",
+		Status:     418,
+		Headers:    map[string]string{"X-Teapot": "true"},
+		Body:       []byte(`{"brewing": true}`),
+	})
+
+	r := testRouter(repo)
+
+	// Capture a request — should return the mock response, not the default 200.
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, httptest.NewRequest(http.MethodPost, "/mock-cap", strings.NewReader(`{"order":"latte"}`)))
+
+	if w.Code != 418 {
+		t.Fatalf("expected mock status 418, got %d", w.Code)
+	}
+	if w.Header().Get("X-Teapot") != "true" {
+		t.Errorf("expected X-Teapot: true, got %q", w.Header().Get("X-Teapot"))
+	}
+	body := strings.TrimSpace(w.Body.String())
+	if body != `{"brewing": true}` {
+		t.Errorf("expected mock body, got %q", body)
+	}
+
+	// Request should still be captured even when mock responds.
+	if len(repo.requests) != 1 {
+		t.Fatalf("expected 1 captured request, got %d", len(repo.requests))
+	}
+	if repo.requests[0].Method != "POST" {
+		t.Errorf("captured method: %s", repo.requests[0].Method)
+	}
+}
+
+func TestMockAutoCreatesEndpointOnSet(t *testing.T) {
+	repo := newFakeRepo()
+	r := testRouter(repo)
+
+	// Set a mock on an endpoint that doesn't exist yet.
+	mockBody := `{"status": 200, "headers": {}, "body": ""}`
+	req := httptest.NewRequest(http.MethodPut, "/e/auto-mock/mock", strings.NewReader(mockBody))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200 OK, got %d: %s", w.Code, w.Body.String())
+	}
+
+	// Endpoint should be auto-created.
+	ep, err := repo.GetEndpoint(nil, "auto-mock")
+	if err != nil {
+		t.Fatalf("endpoint was not auto-created: %v", err)
+	}
+	if ep.ID != "auto-mock" {
+		t.Errorf("expected endpoint id 'auto-mock', got %q", ep.ID)
+	}
+}

internal/handler/inspect.go

@@ -0,0 +1,344 @@
+package handler
+
+import (
+	"encoding/json"
+	"fmt"
+	"html/template"
+	"net/http"
+	"time"
+
+	"github.com/elfoundation/hatch/internal/store"
+)
+
+// inspectPageData is passed to the inspect template.
+type inspectPageData struct {
+	EndpointID string
+	Requests   []*store.Request
+}
+
+// inspectTemplate is the server-rendered HTML for the inspect page.
+var inspectTemplate = template.Must(template.New("inspect").Funcs(template.FuncMap{
+	"prettyJSON": prettyJSON,
+	"formatTime": formatTime,
+}).Parse(`<!DOCTYPE html>
+<html lang="en">
+<head>
+<meta charset="utf-8">
+<meta name="viewport" content="width=device-width, initial-scale=1">
+<title>Hatch — {{.EndpointID}}</title>
+<style>
+  :root { color-scheme: light dark; }
+  body { font-family: system-ui, sans-serif; max-width: 960px; margin: 0 auto; padding: 1rem; }
+  h1 { font-size: 1.25rem; margin: 0 0 0.25rem; }
+  .endpoint-url { color: #666; font-family: monospace; font-size: 0.85rem; margin-bottom: 1.5rem; word-break: break-all; }
+  .request { border: 1px solid #e0e0e0; border-radius: 8px; margin-bottom: 1rem; overflow: hidden; }
+  .request-header { display: flex; align-items: center; gap: 0.5rem; padding: 0.75rem 1rem; background: #f5f5f5; cursor: pointer; user-select: none; }
+  .request-header:hover { background: #eee; }
+  @media (prefers-color-scheme: dark) {
+    .request { border-color: #333; }
+    .request-header { background: #1a1a1a; }
+    .request-header:hover { background: #222; }
+    .endpoint-url { color: #aaa; }
+  }
+  .method { font-weight: 700; font-size: 0.8rem; padding: 2px 8px; border-radius: 4px; }
+  .method.GET { background: #d4edda; color: #155724; }
+  .method.POST { background: #cce5ff; color: #004085; }
+  .method.PUT { background: #fff3cd; color: #856404; }
+  .method.PATCH { background: #fff3cd; color: #856404; }
+  .method.DELETE { background: #f8d7da; color: #721c24; }
+  .path { font-family: monospace; font-size: 0.9rem; flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+  .time { color: #999; font-size: 0.8rem; white-space: nowrap; }
+  .request-body { padding: 1rem; display: none; }
+  .request-body.open { display: block; }
+  .section { margin-bottom: 0.75rem; }
+  .section-label { font-size: 0.75rem; font-weight: 600; text-transform: uppercase; color: #888; margin-bottom: 0.25rem; }
+  pre { background: #f8f8f8; border: 1px solid #e0e0e0; border-radius: 4px; padding: 0.75rem; font-size: 0.8rem; overflow-x: auto; margin: 0; white-space: pre-wrap; word-break: break-all; }
+  @media (prefers-color-scheme: dark) { pre { background: #111; border-color: #333; } }
+  .empty { text-align: center; color: #999; padding: 3rem 0; }
+  .empty h2 { font-size: 1rem; margin-bottom: 0.5rem; }
+  .empty code { background: #f0f0f0; padding: 2px 6px; border-radius: 3px; }
+  @media (prefers-color-scheme: dark) { .empty code { background: #222; } }
+
+  .replay-btn { margin-left: auto; padding: 4px 12px; font-size: 0.8rem; border: 1px solid #007bff; background: #007bff; color: #fff; border-radius: 4px; cursor: pointer; }
+  .replay-btn:hover { background: #0056b3; }
+  .replay-btn:disabled { opacity: 0.6; cursor: not-allowed; }
+  .replay-panel { display: none; padding: 1rem; border-top: 1px solid #e0e0e0; }
+  @media (prefers-color-scheme: dark) { .replay-panel { border-color: #333; } }
+  .replay-panel.open { display: block; }
+  .replay-url-input { width: 100%; padding: 0.5rem; border: 1px solid #ccc; border-radius: 4px; font-family: monospace; font-size: 0.85rem; box-sizing: border-box; margin-bottom: 0.5rem; }
+  .replay-url-input:focus { outline: none; border-color: #007bff; box-shadow: 0 0 0 2px rgba(0,123,255,0.25); }
+  .replay-actions { display: flex; gap: 0.5rem; align-items: center; }
+  .replay-send-btn { padding: 6px 16px; border: none; background: #28a745; color: #fff; border-radius: 4px; cursor: pointer; font-size: 0.85rem; }
+  .replay-send-btn:hover { background: #218838; }
+  .replay-send-btn:disabled { opacity: 0.6; cursor: not-allowed; }
+  .replay-cancel-btn { padding: 6px 12px; border: 1px solid #ccc; background: transparent; border-radius: 4px; cursor: pointer; font-size: 0.85rem; }
+  .replay-result { margin-top: 0.75rem; }
+  .replay-error { color: #dc3545; font-size: 0.85rem; }
+  .status-badge { display: inline-block; padding: 2px 8px; border-radius: 4px; font-size: 0.8rem; font-weight: 600; margin-right: 0.5rem; }
+  .status-2xx { background: #d4edda; color: #155724; }
+  .status-3xx { background: #fff3cd; color: #856404; }
+  .status-4xx { background: #f8d7da; color: #721c24; }
+  .status-5xx { background: #f8d7da; color: #721c24; }
+</style>
+</head>
+<body>
+<h1>Hatch</h1>
+<div class="endpoint-url">Endpoint: <strong>{{.EndpointID}}</strong></div>
+
+{{if .Requests}}
+  {{range .Requests}}
+  <div class="request" id="req-{{.ID}}">
+    <div class="request-header" onclick="toggleRequest('{{.ID}}')">
+      <span class="method {{.Method}}">{{.Method}}</span>
+      <span class="path">{{.Path}}</span>
+      <span class="time" title="{{.CreatedAt}}">{{formatTime .CreatedAt}}</span>
+      <button class="replay-btn" onclick="event.stopPropagation(); openReplay('{{.ID}}')" title="Replay this request">&#x21BA; Replay</button>
+    </div>
+    <div class="request-body" id="body-{{.ID}}">
+      {{if .Headers}}
+      <div class="section">
+        <div class="section-label">Headers</div>
+        <pre>{{prettyJSON .Headers}}</pre>
+      </div>
+      {{end}}
+      {{if .Query}}
+      <div class="section">
+        <div class="section-label">Query</div>
+        <pre>{{.Query}}</pre>
+      </div>
+      {{end}}
+      {{if .Body}}
+      <div class="section">
+        <div class="section-label">Body</div>
+        <pre>{{printf "%s" .Body}}</pre>
+      </div>
+      {{end}}
+    </div>
+    <div class="replay-panel" id="replay-{{.ID}}">
+      <input type="text" class="replay-url-input" id="replay-url-{{.ID}}" placeholder="https://myapp.local/webhook" value="">
+      <div class="replay-actions">
+        <button class="replay-send-btn" onclick="doReplay('{{.ID}}')">Send</button>
+        <button class="replay-cancel-btn" onclick="closeReplay('{{.ID}}')">Cancel</button>
+        <span class="replay-error" id="replay-error-{{.ID}}"></span>
+      </div>
+      <div class="replay-result" id="replay-result-{{.ID}}"></div>
+    </div>
+  </div>
+  {{end}}
+{{else}}
+  <div class="empty">
+    <h2>Waiting for requests...</h2>
+    <p>Send a request to <code>/{{.EndpointID}}</code> to see it appear here.</p>
+  </div>
+{{end}}
+
+<script>
+function toggleRequest(id) {
+  document.getElementById('body-' + id).classList.toggle('open');
+}
+
+function openReplay(id) {
+  document.querySelectorAll('.replay-panel.open').forEach(function(p) { p.classList.remove('open'); });
+  document.getElementById('replay-' + id).classList.add('open');
+  var input = document.getElementById('replay-url-' + id);
+  input.focus();
+  if (!input.value) input.value = 'http://localhost:8080';
+  document.getElementById('replay-result-' + id).innerHTML = '';
+  document.getElementById('replay-error-' + id).textContent = '';
+}
+
+function closeReplay(id) {
+  document.getElementById('replay-' + id).classList.remove('open');
+}
+
+function doReplay(id) {
+  var targetUrl = document.getElementById('replay-url-' + id).value.trim();
+  if (!targetUrl) {
+    document.getElementById('replay-error-' + id).textContent = 'Please enter a target URL.';
+    return;
+  }
+  var sendBtn = document.querySelector('#replay-' + id + ' .replay-send-btn');
+  var errorEl = document.getElementById('replay-error-' + id);
+  var resultEl = document.getElementById('replay-result-' + id);
+  var endpointId = window.location.pathname.replace(/^\/e\//, '');
+
+  sendBtn.disabled = true;
+  errorEl.textContent = '';
+  resultEl.innerHTML = '<em>Sending...</em>';
+
+  fetch('/e/' + endpointId + '/requests/' + id + '/replay', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ target_url: targetUrl })
+  }).then(function(resp) {
+    return resp.json().then(function(data) { return { status: resp.status, data: data }; });
+  }).then(function(result) {
+    if (result.data.error) {
+      errorEl.textContent = result.data.error;
+      resultEl.innerHTML = '';
+    } else {
+      renderReplayResult(resultEl, result.data);
+    }
+  }).catch(function(err) {
+    errorEl.textContent = 'Network error: ' + err.message;
+    resultEl.innerHTML = '';
+  }).finally(function() { sendBtn.disabled = false; });
+}
+
+function renderReplayResult(el, data) {
+  var sc = 'status-2xx';
+  if (data.status >= 300 && data.status < 400) sc = 'status-3xx';
+  else if (data.status >= 400 && data.status < 500) sc = 'status-4xx';
+  else if (data.status >= 500) sc = 'status-5xx';
+  var html = '<div class="section"><div class="section-label">Response</div>';
+  html += '<span class="status-badge ' + sc + '">' + data.status + '</span></div>';
+  if (data.headers && Object.keys(data.headers).length > 0) {
+    html += '<div class="section"><div class="section-label">Response Headers</div><pre>';
+    for (var h in data.headers) { html += escapeHtml(h) + ': ' + escapeHtml(data.headers[h]) + '\n'; }
+    html += '</pre></div>';
+  }
+  if (data.body) {
+    html += '<div class="section"><div class="section-label">Response Body</div><pre>' + escapeHtml(data.body) + '</pre></div>';
+  }
+  el.innerHTML = html;
+}
+
+function formatTimeStr(ts) {
+  try { var d = new Date(ts); if (isNaN(d.getTime())) return ts; } catch(_) { return ts; }
+  var now = new Date();
+  var diff = Math.floor((now - d) / 1000);
+  if (diff < 5) return 'just now';
+  if (diff < 60) return diff + 's ago';
+  if (diff < 3600) return Math.floor(diff / 60) + 'm ago';
+  if (diff < 86400) return Math.floor(diff / 3600) + 'h ago';
+  if (diff < 604800) return Math.floor(diff / 86400) + 'd ago';
+  return d.toLocaleDateString('en-US', { month: 'short', day: 'numeric' }) + ', ' + d.toLocaleTimeString('en-US', { hour: '2-digit', minute: '2-digit' });
+}
+
+function buildRequestBody(req) {
+  var html = '';
+  if (req.headers) {
+    var h = req.headers;
+    if (typeof h === 'string') { try { h = JSON.parse(h); } catch(_) { h = null; } }
+    if (h && Object.keys(h).length > 0) {
+      html += '<div class="section"><div class="section-label">Headers</div><pre>' + escapeHtml(JSON.stringify(h, null, 2)) + '</pre></div>';
+    }
+  }
+  if (req.query) {
+    html += '<div class="section"><div class="section-label">Query</div><pre>' + escapeHtml(req.query) + '</pre></div>';
+  }
+  if (req.body) {
+    var b = typeof req.body === 'string' ? req.body : '';
+    if (b) {
+      html += '<div class="section"><div class="section-label">Body</div><pre>' + escapeHtml(b) + '</pre></div>';
+    }
+  }
+  return html;
+}
+
+function escapeHtml(str) {
+  var div = document.createElement('div');
+  div.appendChild(document.createTextNode(str));
+  return div.innerHTML;
+}
+
+// Live updates via EventSource
+(function() {
+  var endpointId = window.location.pathname.replace(/^\/e\//, '');
+  if (!endpointId) return;
+  var es = new EventSource('/e/' + endpointId + '/events');
+  es.onmessage = function(e) {
+    try {
+      var req = JSON.parse(e.data);
+      var empty = document.querySelector('.empty');
+      if (empty) empty.remove();
+      var div = document.createElement('div');
+      div.className = 'request';
+      div.id = 'req-' + req.id;
+      div.innerHTML = '<div class="request-header" onclick="toggleRequest(\'' + req.id + '\')">' +
+        '<span class="method ' + req.method + '">' + req.method + '</span>' +
+        '<span class="path">' + req.path + '</span>' +
+        '<span class="time" title="' + req.created_at + '">' + formatTimeStr(req.created_at) + '</span>' +
+        '<button class="replay-btn" onclick="event.stopPropagation(); openReplay(\'' + req.id + '\')">&#x21BA; Replay</button>' +
+        '</div>' +
+        '<div class="request-body" id="body-' + req.id + '">' + buildRequestBody(req) + '</div>' +
+        '<div class="replay-panel" id="replay-' + req.id + '">' +
+        '<input type="text" class="replay-url-input" id="replay-url-' + req.id + '" placeholder="https://myapp.local/webhook" value="">' +
+        '<div class="replay-actions">' +
+        '<button class="replay-send-btn" onclick="doReplay(\'' + req.id + '\')">Send</button>' +
+        '<button class="replay-cancel-btn" onclick="closeReplay(\'' + req.id + '\')">Cancel</button>' +
+        '<span class="replay-error" id="replay-error-' + req.id + '"></span></div>' +
+        '<div class="replay-result" id="replay-result-' + req.id + '"></div></div>';
+      var ref = document.querySelector('.endpoint-url');
+      ref.insertAdjacentElement('afterend', div);
+    } catch(_) {}
+  };
+})();
+</script>
+</body>
+</html>
+`))
+
+// HandleInspect serves the inspect page at GET /e/{endpointID}.
+func HandleInspect(repo store.Repository) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		endpointID := r.PathValue("endpointID")
+		if endpointID == "" {
+			http.Error(w, "missing endpoint ID", http.StatusBadRequest)
+			return
+		}
+		if _, err := repo.GetEndpoint(r.Context(), endpointID); err != nil {
+			repo.CreateEndpoint(r.Context(), endpointID)
+		}
+		requests, err := repo.ListRequests(r.Context(), endpointID, 100)
+		if err != nil {
+			http.Error(w, "failed to list requests", http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "text/html; charset=utf-8")
+		inspectTemplate.Execute(w, inspectPageData{
+			EndpointID: endpointID,
+			Requests:   requests,
+		})
+	}
+}
+
+// prettyJSON formats a JSON string with indentation.
+func prettyJSON(raw string) string {
+	var v interface{}
+	if err := json.Unmarshal([]byte(raw), &v); err != nil {
+		return raw
+	}
+	b, err := json.MarshalIndent(v, "", "  ")
+	if err != nil {
+		return raw
+	}
+	return string(b)
+}
+
+// formatTime displays an ISO 8601 timestamp as a short relative or absolute string.
+func formatTime(raw string) string {
+	t, err := time.Parse("2006-01-02T15:04:05.000Z07:00", raw)
+	if err != nil {
+		// Try a few common variants.
+		t, err = time.Parse("2006-01-02T15:04:05Z07:00", raw)
+	}
+	if err != nil {
+		return raw
+	}
+	d := time.Since(t)
+	switch {
+	case d < 5*time.Second:
+		return "just now"
+	case d < time.Minute:
+		return fmt.Sprintf("%ds ago", int(d.Seconds()))
+	case d < time.Hour:
+		return fmt.Sprintf("%dm ago", int(d.Minutes()))
+	case d < 24*time.Hour:
+		return fmt.Sprintf("%dh ago", int(d.Hours()))
+	case d < 7*24*time.Hour:
+		return fmt.Sprintf("%dd ago", int(d.Hours()/24))
+	default:
+		return t.Format("Jan 2, 15:04")
+	}
+}

internal/handler/mock.go

@@ -0,0 +1,35 @@
+package handler
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/elfoundation/hatch/internal/store"
+)
+
+// HandleMock handles PUT /e/{endpointID}/mock.
+func HandleMock(repo store.Repository) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		endpointID := r.PathValue("endpointID")
+		if endpointID == "" {
+			writeError(w, http.StatusBadRequest, "missing endpoint ID")
+			return
+		}
+		if _, err := repo.GetEndpoint(r.Context(), endpointID); err != nil {
+			repo.CreateEndpoint(r.Context(), endpointID)
+		}
+		var mock store.MockConfig
+		if err := json.NewDecoder(r.Body).Decode(&mock); err != nil {
+			writeError(w, http.StatusBadRequest, "invalid JSON body: "+err.Error())
+			return
+		}
+		mock.EndpointID = endpointID
+		if err := repo.SetMock(r.Context(), &mock); err != nil {
+			writeError(w, http.StatusInternalServerError, "failed to set mock: "+err.Error())
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		json.NewEncoder(w).Encode(map[string]string{"status": "ok"})
+	}
+}

internal/handler/replay.go

@@ -0,0 +1,196 @@
+package handler
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+
+	"github.com/elfoundation/hatch/internal/store"
+)
+
+const maxReplayBodyBytes = 64 * 1024
+
+type replayRequest struct {
+	TargetURL string `json:"target_url"`
+}
+
+type replayResponse struct {
+	Status  int               `json:"status"`
+	Headers map[string]string `json:"headers"`
+	Body    string            `json:"body"`
+	Error   string            `json:"error,omitempty"`
+}
+
+func HandleReplay(repo store.Repository) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		requestID := r.PathValue("requestID")
+		if requestID == "" {
+			writeError(w, http.StatusBadRequest, "missing request_id")
+			return
+		}
+
+		var replay replayRequest
+		if err := json.NewDecoder(r.Body).Decode(&replay); err != nil {
+			writeError(w, http.StatusBadRequest, "invalid JSON body: "+err.Error())
+			return
+		}
+		if replay.TargetURL == "" {
+			writeError(w, http.StatusBadRequest, "target_url is required")
+			return
+		}
+
+		target, err := url.Parse(replay.TargetURL)
+		if err != nil {
+			writeError(w, http.StatusBadRequest, "invalid target_url: "+err.Error())
+			return
+		}
+		if target.Scheme != "http" && target.Scheme != "https" {
+			writeError(w, http.StatusBadRequest, "target_url scheme must be http or https")
+			return
+		}
+
+		if !allowPrivateReplay() && isPrivateAddr(target.Host) {
+			writeError(w, http.StatusForbidden, "replay to private/loopback addresses is denied. Set HATCH_ALLOW_PRIVATE_REPLAY=true to allow")
+			return
+		}
+
+		capReq, err := repo.GetRequest(r.Context(), requestID)
+		if err != nil {
+			writeError(w, http.StatusNotFound, "request not found: "+err.Error())
+			return
+		}
+
+		replayResult, err := doReplay(capReq, target)
+		if err != nil {
+			writeError(w, http.StatusBadGateway, "replay failed: "+err.Error())
+			return
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		json.NewEncoder(w).Encode(replayResult)
+	}
+}
+
+func doReplay(capReq *store.Request, targetURL *url.URL) (*replayResponse, error) {
+	outURL := *targetURL
+	outURL.Path = joinPath(targetURL.Path, capReq.Path)
+	if capReq.Query != "" {
+		outURL.RawQuery = capReq.Query
+	}
+
+	var bodyReader io.Reader
+	if capReq.Body != nil && len(capReq.Body) > 0 {
+		bodyReader = strings.NewReader(string(capReq.Body))
+	}
+
+	req, err := http.NewRequest(capReq.Method, outURL.String(), bodyReader)
+	if err != nil {
+		return nil, fmt.Errorf("building request: %w", err)
+	}
+
+	var headers map[string]string
+	if capReq.Headers != "" {
+		if err := json.Unmarshal([]byte(capReq.Headers), &headers); err != nil {
+			headers = nil
+		}
+	}
+	for k, v := range headers {
+		if isHopByHop(k) {
+			continue
+		}
+		req.Header.Set(k, v)
+	}
+
+	client := &http.Client{
+		CheckRedirect: func(req *http.Request, via []*http.Request) error {
+			if !allowPrivateReplay() && isPrivateAddr(req.URL.Host) {
+				return fmt.Errorf("redirect to private address %s denied", req.URL.Host)
+			}
+			if len(via) >= 10 {
+				return fmt.Errorf("too many redirects")
+			}
+			return nil
+		},
+	}
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("sending request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(io.LimitReader(resp.Body, maxReplayBodyBytes))
+	if err != nil {
+		return nil, fmt.Errorf("reading response: %w", err)
+	}
+
+	respHeaders := make(map[string]string, len(resp.Header))
+	for k, vs := range resp.Header {
+		respHeaders[k] = strings.Join(vs, ", ")
+	}
+
+	return &replayResponse{
+		Status:  resp.StatusCode,
+		Headers: respHeaders,
+		Body:    string(body),
+	}, nil
+}
+
+// isPrivateAddr reports whether addr falls within a private, loopback, or reserved range.
+func isPrivateAddr(hostport string) bool {
+	host, _, err := net.SplitHostPort(hostport)
+	if err != nil {
+		host = hostport
+	}
+	if host == "" {
+		return false
+	}
+
+	// String-based checks first (catch names and the unspecified address 0.0.0.0).
+	if host == "localhost" || host == "0.0.0.0" || host == "::1" || host == "[::1]" {
+		return true
+	}
+
+	ip := net.ParseIP(host)
+	if ip != nil {
+		return ip.IsLoopback() || ip.IsPrivate() || ip.IsLinkLocalUnicast() || ip.IsLinkLocalMulticast()
+	}
+	return false
+}
+
+func allowPrivateReplay() bool {
+	return strings.EqualFold(os.Getenv("HATCH_ALLOW_PRIVATE_REPLAY"), "true")
+}
+
+var hopByHopHeaders = map[string]bool{
+	"connection":          true,
+	"keep-alive":          true,
+	"proxy-authenticate":  true,
+	"proxy-authorization": true,
+	"te":                  true,
+	"trailer":             true,
+	"transfer-encoding":   true,
+	"upgrade":             true,
+}
+
+func isHopByHop(header string) bool {
+	return hopByHopHeaders[strings.ToLower(header)]
+}
+
+func joinPath(base, extra string) string {
+	base = strings.TrimRight(base, "/")
+	extra = strings.TrimLeft(extra, "/")
+	if base == "" {
+		return "/" + extra
+	}
+	if extra == "" {
+		return base
+	}
+	return base + "/" + extra
+}

internal/handler/replay_test.go

@@ -0,0 +1,236 @@
+package handler
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/elfoundation/hatch/internal/store"
+)
+
+func TestReplayMissingTargetURL(t *testing.T) {
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "ep")
+	repo.AppendRequest(nil, "ep", &store.Request{Method: "POST", Path: "/webhook", Headers: "{}"})
+	reqID := repo.requests[0].ID
+
+	r := testRouter(repo)
+	body := `{}`
+	req := httptest.NewRequest(http.MethodPost, "/e/ep/requests/"+reqID+"/replay", strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusBadRequest {
+		t.Fatalf("expected 400, got %d", w.Code)
+	}
+	var resp map[string]string
+	json.NewDecoder(w.Body).Decode(&resp)
+	if !strings.Contains(resp["error"], "target_url") {
+		t.Errorf("expected target_url error, got %v", resp)
+	}
+}
+
+func TestReplayInvalidScheme(t *testing.T) {
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "ep")
+	repo.AppendRequest(nil, "ep", &store.Request{Method: "GET", Path: "/", Headers: "{}"})
+	reqID := repo.requests[0].ID
+
+	r := testRouter(repo)
+	body := `{"target_url": "ftp://bad.scheme/"}`
+	req := httptest.NewRequest(http.MethodPost, "/e/ep/requests/"+reqID+"/replay", strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusBadRequest {
+		t.Fatalf("expected 400, got %d", w.Code)
+	}
+}
+
+func TestReplaySSRFBlocksLocalhost(t *testing.T) {
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "ep")
+	repo.AppendRequest(nil, "ep", &store.Request{Method: "GET", Path: "/", Headers: "{}"})
+	reqID := repo.requests[0].ID
+
+	r := testRouter(repo)
+	body := `{"target_url": "http://localhost:8080/"}`
+	req := httptest.NewRequest(http.MethodPost, "/e/ep/requests/"+reqID+"/replay", strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusForbidden {
+		t.Fatalf("expected 403 for localhost, got %d", w.Code)
+	}
+}
+
+func TestReplaySSRFBlocksPrivate(t *testing.T) {
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "ep")
+	repo.AppendRequest(nil, "ep", &store.Request{Method: "GET", Path: "/", Headers: "{}"})
+	reqID := repo.requests[0].ID
+
+	r := testRouter(repo)
+	for _, addr := range []string{
+		"http://10.0.0.1:80/",
+		"http://172.16.0.1:80/",
+		"http://192.168.1.1:80/",
+		"http://127.0.0.1:80/",
+		"http://[::1]:80/",
+		"http://0.0.0.0:80/",
+	} {
+		body := `{"target_url": "` + addr + `"}`
+		req := httptest.NewRequest(http.MethodPost, "/e/ep/requests/"+reqID+"/replay", strings.NewReader(body))
+		req.Header.Set("Content-Type", "application/json")
+		w := httptest.NewRecorder()
+		r.ServeHTTP(w, req)
+		if w.Code != http.StatusForbidden {
+			t.Errorf("expected 403 for %s, got %d", addr, w.Code)
+		}
+	}
+}
+
+func TestReplayNotFound(t *testing.T) {
+	repo := newFakeRepo()
+	r := testRouter(repo)
+	body := `{"target_url": "https://example.com/"}`
+	req := httptest.NewRequest(http.MethodPost, "/e/ep/requests/nonexistent/replay", strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("expected 404, got %d", w.Code)
+	}
+}
+
+func TestReplaySuccess(t *testing.T) {
+	// Start a local sink server that echoes back what it receives.
+	sink := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("X-Sink", "yes")
+		w.WriteHeader(http.StatusCreated)
+		w.Write([]byte(`{"received": true}`))
+	}))
+	defer sink.Close()
+
+	repo := newFakeRepo()
+	repo.CreateEndpoint(nil, "ep")
+	repo.AppendRequest(nil, "ep", &store.Request{
+		Method:  "POST",
+		Path:    "/webhook",
+		Headers: `{"Content-Type":"application/json","X-Custom":"val"}`,
+		Query:   "foo=bar",
+		Body:    []byte(`{"msg":"hello"}`),
+	})
+	reqID := repo.requests[0].ID
+
+	// Set env to allow private replay since httptest server is on loopback.
+	t.Setenv("HATCH_ALLOW_PRIVATE_REPLAY", "true")
+
+	r := testRouter(repo)
+	body := `{"target_url": "` + sink.URL + `"}`
+	req := httptest.NewRequest(http.MethodPost, "/e/ep/requests/"+reqID+"/replay", strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
+	}
+
+	var resp replayResponse
+	if err := json.NewDecoder(w.Body).Decode(&resp); err != nil {
+		t.Fatalf("failed to decode response: %v", err)
+	}
+	if resp.Status != 201 {
+		t.Errorf("expected status 201, got %d", resp.Status)
+	}
+	if resp.Headers["X-Sink"] != "yes" {
+		t.Errorf("expected X-Sink header, got %v", resp.Headers)
+	}
+	if resp.Body != `{"received": true}` {
+		t.Errorf("expected body, got %q", resp.Body)
+	}
+}
+
+func TestReplayE2ECaptureThenReplay(t *testing.T) {
+	// E2E: capture a request, then replay it to a sink, verify the sink received it.
+
+	// Step 1: Start a sink.
+	sink := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		json.NewEncoder(w).Encode(map[string]interface{}{
+			"method": r.Method,
+			"path":   r.URL.Path,
+			"query":  r.URL.RawQuery,
+			"body":   "received",
+		})
+	}))
+	defer sink.Close()
+
+	// Step 2: Capture a request.
+	repo := newFakeRepo()
+	rt := testRouter(repo)
+
+	captureReq := httptest.NewRequest("POST", "/e2e-test", strings.NewReader(`{"order":"1"}`))
+	captureReq.Header.Set("X-Test", "hello")
+	captureW := httptest.NewRecorder()
+	rt.ServeHTTP(captureW, captureReq)
+
+	if len(repo.requests) != 1 {
+		t.Fatalf("expected 1 captured request, got %d", len(repo.requests))
+	}
+	captured := repo.requests[0]
+	if captured.Method != "POST" {
+		t.Errorf("captured method: %s", captured.Method)
+	}
+
+	// Step 3: Replay it to the sink.
+	t.Setenv("HATCH_ALLOW_PRIVATE_REPLAY", "true")
+
+	replayBody := `{"target_url": "` + sink.URL + `"}`
+	replayReq := httptest.NewRequest("POST", "/e/e2e-test/requests/"+captured.ID+"/replay", strings.NewReader(replayBody))
+	replayReq.Header.Set("Content-Type", "application/json")
+	replayW := httptest.NewRecorder()
+	rt.ServeHTTP(replayW, replayReq)
+
+	if replayW.Code != http.StatusOK {
+		t.Fatalf("replay failed with %d: %s", replayW.Code, replayW.Body.String())
+	}
+
+	var resp replayResponse
+	json.NewDecoder(replayW.Body).Decode(&resp)
+	if resp.Status != 200 {
+		t.Errorf("replay response status: %d", resp.Status)
+	}
+}
+
+func TestIsPrivateAddr(t *testing.T) {
+	tests := []struct {
+		addr string
+		want bool
+	}{
+		{"localhost:8080", true},
+		{"127.0.0.1:9090", true},
+		{"[::1]:80", true},
+		{"10.0.0.5:443", true},
+		{"172.16.0.1:80", true},
+		{"192.168.1.1:3000", true},
+		{"0.0.0.0:8080", true},
+		{"example.com:443", false},
+		{"93.184.216.34:80", false},
+		{"8.8.8.8:53", false},
+	}
+	for _, tc := range tests {
+		got := isPrivateAddr(tc.addr)
+		if got != tc.want {
+			t.Errorf("isPrivateAddr(%q) = %v, want %v", tc.addr, tc.want, got)
+		}
+	}
+}

internal/handler/sse.go

@@ -0,0 +1,125 @@
+package handler
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"sync"
+
+	"github.com/elfoundation/hatch/internal/store"
+)
+
+// sseHub manages SSE subscribers per endpoint.
+type sseHub struct {
+	mu   sync.RWMutex
+	subs map[string]map[chan []byte]struct{}
+}
+
+var hub = &sseHub{
+	subs: make(map[string]map[chan []byte]struct{}),
+}
+
+func (h *sseHub) subscribe(endpointID string) chan []byte {
+	ch := make(chan []byte, 64)
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	if h.subs[endpointID] == nil {
+		h.subs[endpointID] = make(map[chan []byte]struct{})
+	}
+	h.subs[endpointID][ch] = struct{}{}
+	return ch
+}
+
+func (h *sseHub) unsubscribe(endpointID string, ch chan []byte) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	delete(h.subs[endpointID], ch)
+	if len(h.subs[endpointID]) == 0 {
+		delete(h.subs, endpointID)
+	}
+}
+
+// sseRequest is the JSON payload sent over SSE.
+// It uses string for Body to avoid base64 encoding.
+type sseRequest struct {
+	ID         string `json:"id"`
+	EndpointID string `json:"endpoint_id"`
+	Method     string `json:"method"`
+	Path       string `json:"path"`
+	Headers    string `json:"headers"`
+	Query      string `json:"query"`
+	Body       string `json:"body"`
+	CreatedAt  string `json:"created_at"`
+}
+
+func (h *sseHub) broadcast(endpointID string, req *store.Request) {
+	h.mu.RLock()
+	defer h.mu.RUnlock()
+	subs := h.subs[endpointID]
+	if subs == nil {
+		return
+	}
+	sseReq := sseRequest{
+		ID:         req.ID,
+		EndpointID: req.EndpointID,
+		Method:     req.Method,
+		Path:       req.Path,
+		Headers:    req.Headers,
+		Query:      req.Query,
+		Body:       string(req.Body),
+		CreatedAt:  req.CreatedAt,
+	}
+	data, err := json.Marshal(sseReq)
+	if err != nil {
+		return
+	}
+	for ch := range subs {
+		select {
+		case ch <- data:
+		default:
+		}
+	}
+}
+
+// broadcastRequest publishes req to SSE subscribers for its endpoint.
+func broadcastRequest(endpointID string, req *store.Request) {
+	hub.broadcast(endpointID, req)
+}
+
+// HandleSSE serves an SSE stream for GET /e/{endpointID}/events.
+func HandleSSE(repo store.Repository) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		endpointID := r.PathValue("endpointID")
+		if endpointID == "" {
+			http.Error(w, "missing endpoint ID", http.StatusBadRequest)
+			return
+		}
+		flusher, ok := w.(http.Flusher)
+		if !ok {
+			http.Error(w, "streaming not supported", http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "text/event-stream")
+		w.Header().Set("Cache-Control", "no-cache")
+		w.Header().Set("Connection", "keep-alive")
+		w.WriteHeader(http.StatusOK)
+		flusher.Flush()
+
+		ch := hub.subscribe(endpointID)
+		defer hub.unsubscribe(endpointID, ch)
+
+		ctx := r.Context()
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case data, ok := <-ch:
+				if !ok {
+					return
+				}
+				fmt.Fprintf(w, "data: %s\n\n", data)
+				flusher.Flush()
+			}
+		}
+	}
+}

internal/store/db.go

@@ -0,0 +1,35 @@
+package store
+
+import (
+	"database/sql"
+	_ "embed"
+	"fmt"
+	"os"
+	"path/filepath"
+	_ "modernc.org/sqlite"
+)
+
+//go:embed schema.sql
+var schemaSQL string
+
+func Open(dbPath string) (Repository, error) {
+	if dbPath == "" { dbPath = filepath.Join("data", "hatch.db") }
+	dir := filepath.Dir(dbPath)
+	if err := os.MkdirAll(dir, 0o755); err != nil {
+		return nil, fmt.Errorf("store: create db dir %s: %w", dir, err)
+	}
+	conn, err := sql.Open("sqlite", dbPath+"?_journal_mode=WAL&_busy_timeout=5000")
+	if err != nil { return nil, fmt.Errorf("store: open %s: %w", dbPath, err) }
+	conn.SetMaxOpenConns(1)
+	if err := migrate(conn); err != nil {
+		conn.Close()
+		return nil, fmt.Errorf("store: migrate: %w", err)
+	}
+	return NewSQLiteRepo(conn)
+}
+
+func migrate(db *sql.DB) error {
+	_, err := db.Exec(schemaSQL)
+	if err != nil { return fmt.Errorf("store/migrate: %w", err) }
+	return nil
+}

internal/store/doc.go

@@ -0,0 +1,2 @@
+// Package store provides the SQLite-backed persistence layer for Hatch.
+package store

internal/store/models.go

@@ -0,0 +1,42 @@
+package store
+
+import "context"
+
+type Endpoint struct {
+	ID        string `json:"id"`
+	URL       string `json:"url"`
+	CreatedAt string `json:"created_at"`
+	UpdatedAt string `json:"updated_at"`
+}
+
+type Request struct {
+	ID         string `json:"id"`
+	EndpointID string `json:"endpoint_id"`
+	Method     string `json:"method"`
+	Path       string `json:"path"`
+	Headers    string `json:"headers"`
+	Query      string `json:"query"`
+	Body       []byte `json:"body"`
+	CreatedAt  string `json:"created_at"`
+}
+
+// MockConfig holds the mock response configuration for an endpoint.
+type MockConfig struct {
+	EndpointID string            `json:"endpoint_id"`
+	Status     int               `json:"status"`
+	Headers    map[string]string `json:"headers"`
+	Body       []byte            `json:"body"`
+}
+
+type Repository interface {
+	CreateEndpoint(ctx context.Context, url string) (*Endpoint, error)
+	GetEndpoint(ctx context.Context, id string) (*Endpoint, error)
+	AppendRequest(ctx context.Context, endpointID string, req *Request) error
+	GetRequest(ctx context.Context, id string) (*Request, error)
+	ListRequests(ctx context.Context, endpointID string, limit int) ([]*Request, error)
+	GetMock(ctx context.Context, endpointID string) (*MockConfig, error)
+	SetMock(ctx context.Context, mock *MockConfig) error
+	Close() error
+}
+
+var _ Repository = (*sqliteRepo)(nil)

internal/store/schema.sql

@@ -0,0 +1,21 @@
+CREATE TABLE IF NOT EXISTS endpoints (
+    id         TEXT NOT NULL PRIMARY KEY,
+    url        TEXT NOT NULL UNIQUE,
+    created_at TEXT NOT NULL,
+    updated_at TEXT NOT NULL,
+    mock_status INTEGER,
+    mock_headers TEXT,
+    mock_body BLOB
+);
+CREATE TABLE IF NOT EXISTS requests (
+    id          TEXT NOT NULL PRIMARY KEY,
+    endpoint_id TEXT NOT NULL REFERENCES endpoints(id),
+    method      TEXT NOT NULL,
+    path        TEXT NOT NULL,
+    headers     TEXT NOT NULL DEFAULT '{}',
+    query       TEXT NOT NULL DEFAULT '',
+    body        BLOB,
+    created_at  TEXT NOT NULL
+);
+CREATE INDEX IF NOT EXISTS idx_requests_endpoint_id ON requests(endpoint_id);
+CREATE INDEX IF NOT EXISTS idx_requests_created_at ON requests(created_at);

internal/store/sqlite_repo.go

@@ -0,0 +1,121 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"github.com/google/uuid"
+)
+
+type sqliteRepo struct{ db *sql.DB }
+
+func NewSQLiteRepo(db *sql.DB) (Repository, error) {
+	if db == nil {
+		return nil, fmt.Errorf("store: nil db")
+	}
+	return &sqliteRepo{db: db}, nil
+}
+
+func (r *sqliteRepo) CreateEndpoint(ctx context.Context, url string) (*Endpoint, error) {
+	now := utcNow()
+	e := &Endpoint{ID: url, URL: url, CreatedAt: now, UpdatedAt: now}
+	_, err := r.db.ExecContext(ctx, `INSERT INTO endpoints (id, url, created_at, updated_at) VALUES (?, ?, ?, ?)`, e.ID, e.URL, e.CreatedAt, e.UpdatedAt)
+	if err != nil {
+		return nil, fmt.Errorf("store: create endpoint: %w", err)
+	}
+	return e, nil
+}
+
+func (r *sqliteRepo) GetEndpoint(ctx context.Context, id string) (*Endpoint, error) {
+	row := r.db.QueryRowContext(ctx, `SELECT id, url, created_at, updated_at FROM endpoints WHERE id = ?`, id)
+	e := &Endpoint{}
+	if err := row.Scan(&e.ID, &e.URL, &e.CreatedAt, &e.UpdatedAt); err != nil {
+		return nil, fmt.Errorf("store: get endpoint: %w", err)
+	}
+	return e, nil
+}
+
+func (r *sqliteRepo) AppendRequest(ctx context.Context, endpointID string, req *Request) error {
+	req.ID = uuid.NewString()
+	req.EndpointID = endpointID
+	req.CreatedAt = utcNow()
+	_, err := r.db.ExecContext(ctx, `INSERT INTO requests (id, endpoint_id, method, path, headers, query, body, created_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?)`,
+		req.ID, req.EndpointID, req.Method, req.Path, req.Headers, req.Query, req.Body, req.CreatedAt)
+	if err != nil {
+		return fmt.Errorf("store: append request: %w", err)
+	}
+	return nil
+}
+
+func (r *sqliteRepo) GetRequest(ctx context.Context, id string) (*Request, error) {
+	row := r.db.QueryRowContext(ctx, `SELECT id, endpoint_id, method, path, headers, query, body, created_at FROM requests WHERE id = ?`, id)
+	req := &Request{}
+	if err := row.Scan(&req.ID, &req.EndpointID, &req.Method, &req.Path, &req.Headers, &req.Query, &req.Body, &req.CreatedAt); err != nil {
+		return nil, fmt.Errorf("store: get request %s: %w", id, err)
+	}
+	return req, nil
+}
+
+func (r *sqliteRepo) ListRequests(ctx context.Context, endpointID string, limit int) ([]*Request, error) {
+	if limit <= 0 {
+		limit = 50
+	}
+	rows, err := r.db.QueryContext(ctx, `SELECT id, endpoint_id, method, path, headers, query, body, created_at FROM requests WHERE endpoint_id = ? ORDER BY created_at DESC LIMIT ?`, endpointID, limit)
+	if err != nil {
+		return nil, fmt.Errorf("store: list requests: %w", err)
+	}
+	defer rows.Close()
+	var out []*Request
+	for rows.Next() {
+		var req Request
+		if err := rows.Scan(&req.ID, &req.EndpointID, &req.Method, &req.Path, &req.Headers, &req.Query, &req.Body, &req.CreatedAt); err != nil {
+			return nil, fmt.Errorf("store: scan request: %w", err)
+		}
+		out = append(out, &req)
+	}
+	return out, rows.Err()
+}
+
+func (r *sqliteRepo) GetMock(ctx context.Context, endpointID string) (*MockConfig, error) {
+	row := r.db.QueryRowContext(ctx, `SELECT mock_status, mock_headers, mock_body FROM endpoints WHERE id = ?`, endpointID)
+	var status sql.NullInt64
+	var headersJSON sql.NullString
+	var body []byte
+	if err := row.Scan(&status, &headersJSON, &body); err != nil {
+		return nil, fmt.Errorf("store: get mock: %w", err)
+	}
+	if !status.Valid {
+		return nil, fmt.Errorf("store: no mock configured for %s", endpointID)
+	}
+	m := &MockConfig{
+		EndpointID: endpointID,
+		Status:     int(status.Int64),
+		Body:       body,
+	}
+	if headersJSON.Valid && headersJSON.String != "" {
+		json.Unmarshal([]byte(headersJSON.String), &m.Headers)
+	}
+	return m, nil
+}
+
+func (r *sqliteRepo) SetMock(ctx context.Context, mock *MockConfig) error {
+	headersJSON, err := json.Marshal(mock.Headers)
+	if err != nil {
+		return fmt.Errorf("store: marshal mock headers: %w", err)
+	}
+	_, err = r.db.ExecContext(ctx,
+		`UPDATE endpoints SET mock_status = ?, mock_headers = ?, mock_body = ? WHERE id = ?`,
+		mock.Status, string(headersJSON), mock.Body, mock.EndpointID,
+	)
+	if err != nil {
+		return fmt.Errorf("store: set mock: %w", err)
+	}
+	return nil
+}
+
+func (r *sqliteRepo) Close() error { return r.db.Close() }
+
+func utcNow() string { return time.Now().UTC().Format("2006-01-02T15:04:05.000Z07:00") }

internal/store/sqlite_repo_test.go

@@ -0,0 +1,234 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"testing"
+	"time"
+)
+
+func openTestRepo(t *testing.T) Repository {
+	t.Helper()
+	db, err := sql.Open("sqlite", ":memory:?_journal_mode=WAL&_foreign_keys=on")
+	if err != nil {
+		t.Fatalf("open in-memory sqlite: %v", err)
+	}
+	db.SetMaxOpenConns(1)
+	if err := migrate(db); err != nil {
+		db.Close()
+		t.Fatalf("migrate: %v", err)
+	}
+	repo, err := NewSQLiteRepo(db)
+	if err != nil {
+		db.Close()
+		t.Fatalf("new sqlite repo: %v", err)
+	}
+	t.Cleanup(func() { repo.Close() })
+	return repo
+}
+
+func TestCreateAndGetEndpoint(t *testing.T) {
+	repo := openTestRepo(t)
+	e, err := repo.CreateEndpoint(context.Background(), "test-one")
+	if err != nil {
+		t.Fatalf("CreateEndpoint: %v", err)
+	}
+	if e.ID == "" {
+		t.Error("expected non-empty ID")
+	}
+	if e.URL != "test-one" {
+		t.Errorf("url: got %q", e.URL)
+	}
+	if e.CreatedAt == "" || e.UpdatedAt == "" {
+		t.Error("expected timestamps")
+	}
+	got, err := repo.GetEndpoint(context.Background(), e.ID)
+	if err != nil {
+		t.Fatalf("GetEndpoint: %v", err)
+	}
+	if got.ID != e.ID || got.URL != e.URL {
+		t.Errorf("got %+v", got)
+	}
+}
+
+func TestGetEndpointNotFound(t *testing.T) {
+	repo := openTestRepo(t)
+	_, err := repo.GetEndpoint(context.Background(), "nonexistent")
+	if err == nil {
+		t.Fatal("expected error")
+	}
+}
+
+func TestCreateEndpointDuplicateURL(t *testing.T) {
+	repo := openTestRepo(t)
+	ctx := context.Background()
+	if _, err := repo.CreateEndpoint(ctx, "dup"); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := repo.CreateEndpoint(ctx, "dup"); err == nil {
+		t.Fatal("expected UNIQUE error")
+	}
+}
+
+func TestAppendAndListRequests(t *testing.T) {
+	repo := openTestRepo(t)
+	ctx := context.Background()
+	e, err := repo.CreateEndpoint(ctx, "reqs-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	r1 := &Request{Method: "POST", Path: "/webhook", Headers: `{"Content-Type":"application/json"}`, Query: "foo=bar", Body: []byte(`{"hello":"world"}`)}
+	if err := repo.AppendRequest(ctx, e.ID, r1); err != nil {
+		t.Fatal(err)
+	}
+	time.Sleep(time.Millisecond)
+	r2 := &Request{Method: "GET", Path: "/webhook", Headers: `{}`}
+	if err := repo.AppendRequest(ctx, e.ID, r2); err != nil {
+		t.Fatal(err)
+	}
+	reqs, err := repo.ListRequests(ctx, e.ID, 10)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(reqs) != 2 {
+		t.Fatalf("got %d requests", len(reqs))
+	}
+	if reqs[0].Method != "GET" {
+		t.Errorf("first: got %s", reqs[0].Method)
+	}
+	if reqs[1].Method != "POST" {
+		t.Errorf("second: got %s", reqs[1].Method)
+	}
+}
+
+func TestGetRequest(t *testing.T) {
+	repo := openTestRepo(t)
+	ctx := context.Background()
+	e, _ := repo.CreateEndpoint(ctx, "getreq-test")
+	r := &Request{Method: "POST", Path: "/webhook", Headers: `{"X-Api-Key":"secret"}`, Query: "a=1", Body: []byte(`{"msg":"hi"}`)}
+	if err := repo.AppendRequest(ctx, e.ID, r); err != nil {
+		t.Fatal(err)
+	}
+	got, err := repo.GetRequest(ctx, r.ID)
+	if err != nil {
+		t.Fatalf("GetRequest: %v", err)
+	}
+	if got.ID != r.ID {
+		t.Errorf("id: got %q want %q", got.ID, r.ID)
+	}
+	if got.Method != "POST" {
+		t.Errorf("method: got %q", got.Method)
+	}
+	if string(got.Body) != `{"msg":"hi"}` {
+		t.Errorf("body: got %q", string(got.Body))
+	}
+}
+
+func TestGetRequestNotFound(t *testing.T) {
+	repo := openTestRepo(t)
+	_, err := repo.GetRequest(context.Background(), "nonexistent")
+	if err == nil {
+		t.Fatal("expected error for nonexistent request")
+	}
+}
+
+func TestSetAndGetMock(t *testing.T) {
+	repo := openTestRepo(t)
+	ctx := context.Background()
+	e, err := repo.CreateEndpoint(ctx, "mock-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	mock := &MockConfig{
+		EndpointID: e.ID,
+		Status:     201,
+		Headers:    map[string]string{"Content-Type": "application/json"},
+		Body:       []byte(`{"mocked": true}`),
+	}
+	if err := repo.SetMock(ctx, mock); err != nil {
+		t.Fatal(err)
+	}
+	got, err := repo.GetMock(ctx, e.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got.Status != 201 {
+		t.Errorf("status: got %d", got.Status)
+	}
+	if string(got.Body) != `{"mocked": true}` {
+		t.Errorf("body: got %q", string(got.Body))
+	}
+}
+
+func TestGetMockNotFound(t *testing.T) {
+	repo := openTestRepo(t)
+	_, err := repo.GetMock(context.Background(), "no-mock")
+	if err == nil {
+		t.Fatal("expected error")
+	}
+}
+
+func TestListRequestsLimit(t *testing.T) {
+	repo := openTestRepo(t)
+	ctx := context.Background()
+	e, _ := repo.CreateEndpoint(ctx, "limit-test")
+	for i := 0; i < 5; i++ {
+		repo.AppendRequest(ctx, e.ID, &Request{Method: "GET", Path: "/"})
+	}
+	reqs, err := repo.ListRequests(ctx, e.ID, 3)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(reqs) != 3 {
+		t.Fatalf("got %d", len(reqs))
+	}
+}
+
+func TestListRequestsEmpty(t *testing.T) {
+	repo := openTestRepo(t)
+	ctx := context.Background()
+	e, _ := repo.CreateEndpoint(ctx, "empty-test")
+	reqs, _ := repo.ListRequests(ctx, e.ID, 10)
+	if len(reqs) != 0 {
+		t.Errorf("got %d", len(reqs))
+	}
+}
+
+func TestAppendRequestBodyBinary(t *testing.T) {
+	repo := openTestRepo(t)
+	ctx := context.Background()
+	e, _ := repo.CreateEndpoint(ctx, "binary-test")
+	body := []byte{0x00, 0x01, 0x02, 0xFF}
+	if err := repo.AppendRequest(ctx, e.ID, &Request{Method: "POST", Path: "/binary", Body: body}); err != nil {
+		t.Fatal(err)
+	}
+	reqs, _ := repo.ListRequests(ctx, e.ID, 1)
+	if len(reqs) != 1 {
+		t.Fatal("expected 1 request")
+	}
+	if len(reqs[0].Body) != 4 {
+		t.Errorf("body len: %d", len(reqs[0].Body))
+	}
+}
+
+func TestMigrateIdempotent(t *testing.T) {
+	db, err := sql.Open("sqlite", ":memory:?_journal_mode=WAL&_foreign_keys=on")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+	db.SetMaxOpenConns(1)
+	if err := migrate(db); err != nil {
+		t.Fatal(err)
+	}
+	if err := migrate(db); err != nil {
+		t.Fatal(err)
+	}
+	var name string
+	if err := db.QueryRow("SELECT name FROM sqlite_master WHERE type='table' AND name='endpoints'").Scan(&name); err != nil {
+		t.Fatalf("endpoints table: %v", err)
+	}
+	if err := db.QueryRow("SELECT name FROM sqlite_master WHERE type='table' AND name='requests'").Scan(&name); err != nil {
+		t.Fatalf("requests table: %v", err)
+	}
+}