Started PostgreSQL — data directory was uninitialized, ran initdb, set password, switched to md5 auth, all 24 migrations applied.

Hardened db.ts — added statement_timeout: 30000, idle_in_transaction_session_timeout: 10000, created transaction() helper (BEGIN/COMMIT/ROLLBACK).
Multi-step API routes wrapped in transactions — Events POST, Conversations POST use atomic blocks.
Fixed leads pagination — status filter pushed into SQL WHERE (no client-side filtering after LIMIT/OFFSET), added SELECT COUNT(*) for total.
Rewrote dashboard — SQL aggregations (COUNT + GROUP BY + date_trunc) replace loading all leads into memory.
Optimized conversations GET — merged duplicate correlated subqueries into single LEFT JOIN LATERAL.
Created migration 021_performance_indexes.sql — 8 missing indexes + set_session_user_context() function caching current_user_hierarchy_level() as session variable (avoids per-query RLS join).
Fixed build error — duplicate const other in conversations route. Also fixed a TypeScript never error in dashboard breakdown map.
Verified — npx tsc --noEmit clean, npm test (13 pass, 7 integration skip gracefully), npx next build succeeds.

tests/lib/jwt.test.ts

@@ -0,0 +1,57 @@
+import { describe, it, expect } from "vitest"
+import { signToken, verifyToken } from "@/lib/jwt"
+
+process.env.JWT_SECRET = "test-secret-that-is-at-least-32-chars-long-for-security"
+
+describe("JWT", () => {
+  it("signs and verifies a valid token", async () => {
+    const token = await signToken({ userId: "user-1", role: "admin" })
+    expect(token).toBeTruthy()
+    expect(typeof token).toBe("string")
+
+    const payload = await verifyToken(token)
+    expect(payload).not.toBeNull()
+    expect(payload!.userId).toBe("user-1")
+    expect(payload!.role).toBe("admin")
+  })
+
+  it("rejects a tampered token", async () => {
+    const token = await signToken({ userId: "user-1", role: "admin" })
+    const tampered = token.slice(0, -5) + "XXXXX"
+    const payload = await verifyToken(tampered)
+    expect(payload).toBeNull()
+  })
+
+  it("rejects an expired token", async () => {
+    const { SignJWT } = await import("jose")
+    const { getJWTSecret } = await import("@/lib/jwt")
+    const expiredToken = await new SignJWT({ userId: "user-1", role: "admin" })
+      .setProtectedHeader({ alg: "HS256" })
+      .setExpirationTime("0s")
+      .sign(getJWTSecret())
+    const payload = await verifyToken(expiredToken)
+    expect(payload).toBeNull()
+  })
+
+  it("rejects a token with invalid signature", async () => {
+    const { SignJWT } = await import("jose")
+    const wrongSecret = new TextEncoder().encode("different-secret-key-for-signing-purposes-only")
+    const token = await new SignJWT({ userId: "user-1", role: "admin" })
+      .setProtectedHeader({ alg: "HS256" })
+      .setExpirationTime("24h")
+      .setIssuedAt()
+      .sign(wrongSecret)
+    const payload = await verifyToken(token)
+    expect(payload).toBeNull()
+  })
+
+  it("returns null for empty token", async () => {
+    const payload = await verifyToken("")
+    expect(payload).toBeNull()
+  })
+
+  it("returns null for garbage token", async () => {
+    const payload = await verifyToken("this.is.not.a.jwt")
+    expect(payload).toBeNull()
+  })
+})