Project management on Next.js 16 (App Router), Postgres (Neon) and Clerk
Project-management layer: user-owned projects, kanban tasks with status/priority, many-to-many assignees, per-project labels, and comment threads.
60 files, 4 tables and 219 lines of schema, verified 2026-08-23 on Next.js 16 (App Router), Postgres (Neon) and Clerk.
15 pinned upstream versions
request path. session validation runs in server components and route handlers, not at the edge
What you're getting
Next.js 16 App Router: file-based routing, server components, and the Edge proxy (Next 16's renamed middleware).
Postgres on Neon via Drizzle ORM and the postgres-js driver.
Clerk: hosted identity (sign-in UI, sessions, user management) mounted via middleware + provider.
Project-management layer: user-owned projects, kanban tasks with status/priority, many-to-many assignees, per-project labels, and comment threads.
Setup
bun add next react react-dom drizzle-orm postgres @clerk/nextjsDATABASE_URLNeon pooled (-pooler) connection stringNEXT_PUBLIC_CLERK_PUBLISHABLE_KEYCLERK_SECRET_KEYCLERK_WEBHOOK_SECRETsvix secret that verifies Clerk webhook signaturesApply the schema with bunx drizzle-kit push
Initialization
Database client
Project-management schema: projects, tasks, assignees, labels & comments
6 tables, 29 columns and 14 indexes and constraints, applied to a live Postgres (Neon) and asserted to materialize.
projects5 columns · 2 indexedtasks7 columns · 2 indexedtask_assignees4 columns · 3 indexedlabels5 columns · 2 indexedtask_labels3 columns · 3 indexedtask_comments5 columns · 2 indexedWhat this schema is built to answer
tasks, served by idx_task_project_status on (project_id, status): equality on both columns is a single index range, and the same index answers a project-wide read through its leading column.
task_assignees, via idx_assignee_user on assignee_id — the only index that reaches work without going through projects. Each hit joins to tasks by primary key.
task_assignees carries the composite unique task_assignees_task_user_unique on (task_id, assignee_id), so a repeat insert is a constraint violation and the handler can stay an idempotent ON CONFLICT DO NOTHING.
task_comments, with idx_comment_task_time on (task_id, created_at) supplying both the filter and the sort order, so the thread comes back without a separate sort step.
task_labels, read backwards through idx_task_label_label on label_id; labels themselves are scoped per project by idx_label_project on project_id.
Projects owned by a usertop-level containers keyed to a Better Auth user via owner_id FK, with active/archived status
Tasks with status, priority & due datethe unit of work scoped to a project, with a composite (project_id, status) index driving board-column queries
Task assignees & per-project labelstask↔user assignment join (unique per pair) and a project-scoped label catalog with a task↔label join table
Task comment threadsappend-only comment rows keyed to a task and a Better Auth author, indexed on (task_id, created_at) for chronological feeds
Verified identity sync (Clerk)
Deploy targets
The app UI
Decisions and compatibility
Auth runs in proxy.ts (Next 16's renamed middleware) on the Edge runtime: it gates on the session cookie's presence only — full session validation happens in Server Components and route handlers, not in the proxy.
prepare: false is mandatory — Neon's pooled endpoint is PgBouncer in transaction mode, where server-side prepared statements break across the pool.
Drizzle is paired here (not Prisma): Prisma's prepared-statement reliance is incompatible with transaction-mode pooling.
Hosted: Clerk owns identity and does NOT create a local `user` table. Store `clerk_user_id` as text without a foreign key, or sync Clerk users into a local table via webhook before relying on FKs to `user`.
Route protection is clerkMiddleware() + auth.protect() in the Next proxy (getAuth() in a React Router loader, or event.context.auth() on Nuxt) — logged-out users bounce to Clerk's hosted sign-in, so there are no self-hosted auth pages to build or maintain.
Keeping the local mirror in sync is a webhook job: a svix-verified webhook route replays user.created / user.updated / user.deleted idempotently into the local `user` row, so app-type foreign keys to `user` resolve even though Clerk is the source of truth.
ClerkProvider (client) wraps the app so the hosted <SignIn/> / <UserButton/> components and hooks work; the publishable key is read client-side, while the secret key is only ever read server-side by clerkMiddleware.
task_assignees carries a composite unique on (task_id, assignee_id) — a user can be assigned to a task at most once; the per-user index on assignee_id backs the 'tasks assigned to me' feed.
Status and priority are stored as text + CHECK (not pgEnum) so new values like 'blocked' or 'critical' ship without an ALTER TYPE migration dance.
Clerk is a hosted identity provider and does not create a local `user` table. This schema's foreign keys to `user` assume a local identity table (as Better Auth provides). With Clerk, store `clerk_user_id` as a text column without a foreign key, or sync Clerk users into a local `users` table via webhook before relying on these FKs.
How this stack fits together
Clerk is a hosted directory, so there is no local user row for projects, tasks, task_assignees, labels, task_labels and task_comments to reference directly. The composer emits an identity mirror and a sync webhook instead, and the foreign keys point at the mirrored row, which is why this cell ships a webhook handler that the library-auth cells in this registry do not.
Postgres (Neon) stores those surrogate keys as uuid, so every foreign key across the 6 tables and 29 columns below is a uuid column. The migration was applied to a live Postgres (Neon) and the tables asserted, not just type-checked.
Project management
Six tables sit on top of Better Auth's identity layer, and their shape is a tracker rather than a tenant. projects is the root, tasks hang off a project, and assignments, labels and comments all hang off a task. Ownership is one owner_id column on projects referencing user.id as text — text because that is what Better Auth issues — and there is no organization or membership table anywhere in the schema. A project has exactly one owner; participation is expressed by task_assignees rows, not by joining a team. tasks carries the state a board reads: status (todo, in_progress, done), priority (low, medium, high, urgent) and a nullable due_date.
Both graded columns are text guarded by named CHECKs, tasks_status_check and tasks_priority_check, instead of pgEnum, so adding a 'blocked' column is a constraint swap on a live table rather than an ALTER TYPE. The one composite index, idx_task_project_status on (project_id, status), is the board itself: a single kanban column is one range on that index, and a project-wide read uses the same index by prefix. Both many-to-many edges are modelled as sets, not logs. task_assignees is unique on (task_id, assignee_id), so re-assigning the same person is idempotent instead of duplicating a row, and idx_assignee_user on assignee_id is the only path into work that does not start from a project — it is what makes a cross-project 'assigned to me' view cheap.
task_labels repeats that shape against the per-project labels catalog, unique on (task_id, label_id) with idx_task_label_label covering the reverse read from a label back to its tasks. task_comments is append-only and indexed on (task_id, created_at), which supplies the filter and the ordering out of one structure. Every foreign key cascades downward on delete: removing a project takes its tasks, and each task takes its assignments, label links and comments with it in one statement. What is not indexed is due_date and priority, so an overdue-everywhere report scans — add that index before you build the screen, not after it starts timing out.
Next.js 16 (App Router)
Next 16's App Router keeps the whole application under src/: the scaffold runs create-next-app with --src-dir and --import-alias @/*, so `@/` resolves to src/* and the verified files land on top of a stock project rather than replacing it. initCode writes the database client to src/lib/db.ts, then appends the auth fragment's own files — identity tables at src/db/auth-schema.ts, the auth instance at src/lib/auth.ts, a catch-all handler under src/app/api/auth/, and src/proxy.ts. Each file has exactly one owner; the framework never re-emits the ones auth brought. Server code has two shapes here and they are not interchangeable. A Server Component runs on the server and imports { db } from "@/lib/db" directly, so a page can await a Drizzle query with no API route in between.
Anything that needs a URL — an OAuth callback, a Polar or Clerk webhook, a mutation posted from the client — is a route handler at src/app/api/<path>/route.ts exporting GET or POST. Session checking is split across two tiers on purpose. src/proxy.ts (Next 16's rename of middleware.ts; under --src-dir it must sit beside src/app or Next silently ignores it) runs on the Edge runtime with a config.matcher listing the guarded prefixes — /dashboard/:path* and /settings/:path* out of the box. It only asks whether a session cookie exists and redirects to /sign-in when it does not: no database round trip at the edge. The authoritative check is auth.api.getSession() inside the Server Component or route handler that actually reads rows.
What that means when you build on it: widening the protected surface is a one-line change to the matcher array, but the proxy is not the security boundary — a request carrying any session cookie reaches the page, and the page decides. Keep the real check next to the data. The UI overlay follows the same split, with auth screens under src/app/(auth)/ and the shell and dashboard under src/app/(app)/.
Postgres (Neon)
Postgres here is Neon reached through postgres-js, with Drizzle's pg-core dialect on top: drizzle({ client }) over a single module-level postgres(DATABASE_URL, { prepare: false }). That flag is not a preference. Neon's pooled (-pooler) endpoint is PgBouncer in transaction mode, where a backend is handed to a different session between statements, so server-side prepared statements break across the pool — and the same constraint is why this axis pairs with Drizzle rather than Prisma. One client per module is enough: PgBouncer and the runtime do the pooling, so there is no globalThis singleton dance. The schemas built on this dialect make three recurring type decisions. Primary keys are uuid(...).primaryKey().defaultRandom(), so ids come from the database. Timestamps are timestamp(..., { withTimezone: true }).defaultNow() — timestamptz, an absolute instant.
Closed value sets are text plus a CHECK constraint rather than pgEnum, so shipping a new role or subscription status is an ordinary constraint change instead of an ALTER TYPE migration. Counters are bigint({ mode: "number" }), and Better Auth's text user.id is referenced as text by the app tables rather than recast. Operationally, transaction-mode pooling forbids anything that spans statements on one backend: LISTEN/NOTIFY, session-scoped SET, advisory-lock sessions, WITH HOLD cursors. Those paths use Neon's direct endpoint instead. The connection client also changes with the deploy target — max: 1 per short-lived serverless instance, a real reused pool (max 10, idle_timeout 20) in a long-running Node process, and on Cloudflare Workers postgres-js is replaced outright by @neondatabase/serverless over HTTP, because Workers have no TCP sockets.
The capability that exists only on this side of the matrix is row-level security. Multi-tenant schemas ship ENABLE plus FORCE ROW LEVEL SECURITY with policies keyed on current_setting('app.current_org_id', true), which withTenant() sets per transaction — unset context yields no rows, so isolation fails closed inside the database rather than in application code. It requires a dedicated NOBYPASSRLS role: Neon's default neondb_owner carries BYPASSRLS, and connecting as it makes every policy silently inert.
Clerk
Clerk keeps identity on its own servers. The emitted app has no auth instance, no password column and no session table: the card at /sign-in is Clerk's <SignIn/> component rendered under a [[...sign-in]] catch-all so Clerk can mount its own verification and SSO-callback sub-routes there, and the endpoints behind it belong to Clerk. What does land in your database is a single mirror table. db/auth-schema.ts declares user with id set to the Clerk user id (text; varchar(255) on MySQL, so the app-type FK columns match exactly), plus email, first and last name, image URL, and an updated_at column used purely as a staleness key. It exists so app-type schemas can foreign-key user the way they would under a self-hosted auth.
It is not a source of truth, and application code should never write to it. Filling that mirror is a webhook job, and this fragment emits the whole path. lib/identity/record.ts holds recordClerkEvent; the mount is a Next route handler at src/app/api/webhooks/clerk/route.ts, an action in app/routes/webhooks.clerk.ts on React Router, or a Nitro .post.ts handler on Nuxt. Clerk delivers through svix, so the route verifies the raw body against CLERK_WEBHOOK_SECRET before anything reaches the database, and the record core is written for a delivery channel that retries and reorders: the staleness comparison lives inside the UPDATE's WHERE clause so an older event cannot clobber newer state, the insert path absorbs a concurrent duplicate (onConflictDoNothing on Postgres, an ER_DUP_ENTRY catch on MySQL), and user.deleted removes the row. Session checks never touch your Postgres.
Next's proxy.ts runs clerkMiddleware() and calls auth.protect() for anything matching createRouteMatcher(["/dashboard(.*)", "/settings(.*)"]); Nuxt reads event.context.auth() inside a Nitro middleware that the @clerk/nuxt module populates. Even the package name is framework-specific — @clerk/nextjs, @clerk/react-router, @clerk/nuxt — which upstreamPkgFor resolves per cell. The trade is concrete. You never build, style or maintain auth screens, and breaking changes arrive with Clerk's releases rather than your lockfile. In exchange, your user rows are eventually consistent with someone else's database, and a webhook you never configured is a table of missing foreign-key targets that only shows up when an app-type insert fails.
