saas-starter

saas-starter

saas-starter is an open-source SvelteKit and Convex template for building your SaaS and running it after launch.

Most starters end where the real work starts: your first customer. This one also tells you who paid, who is stuck, and who was hit by a bug.

Runs in production at Cadenza, the hosted version of LinkedIn MCP .

Live demo | Docs | Quick start

Why you can build on it

• Nothing lands here on spec. A feature only moves into the template once one of my products uses it in production.
• Fixes reach every product. Cadenza has reviewed 158 template commits in three syncs and taken over 120 of them, among them a checkout bug that silently dead-ended every upgrade path. Each was fixed once, here.
• It stays maintained because my own products run on it. When the base breaks, my products break first.
• Fixes stay fixed. When the right fix was not obvious and the mistake is still easy to write, the fix ships with a guard at the earliest point that catches it again: a type, a lint rule, a static check or a focused test. CI asks every fix for its verdict. How guards work.

The feedback loop after launch

Each step is wired in. The conversations stay yours.

Step	What the template does
Launch	Pushes deploy, and pull requests get previews. Analytics, error tracking and admin metrics are wired in before your first user.
Talk to users	New users get a personal welcome email from you, and replies reach your inbox. The support AI answers and hands you threads that need a human.
Learn what they do	You get an email when a customer first pays, with what they did before paying. People who never paid and customers who cancel are asked what was missing.
Fix it and tell them	After a production fix, an agent can find who the evidence shows was hit and draft one email for you to approve.

Each step turns on once its service is connected, such as Resend for email or the Autumn webhook for payments. The feature docs list what each one needs.

Under that: auth with passkeys and OAuth, plan limits with an upgrade path, admin with impersonation and an audit log, markdown pages and /llms.txt for AI agents, four languages, and automated WCAG 2.1 AA checks. All features.

Staying up to date

Your product is its own repository with its own branding and features. Template changes still reach it, and your fixes can travel back:

• Down: bun run upstream:sync finds where your product split off, bun run upstream:changes lists every template commit since, and an agent skill reviews each one against what your product changed.
• Up: bun run upstream:report measures which of your fixes touched template code, so you can send the ones that matter back and every product gets them.

Pick how your product receives template changes before you create it: update models.

Quick Start

Start the app with a local Convex backend and a seeded admin account.

Create a project with the CLI. It downloads a pinned template revision, runs bun run setup with your branding, and installs dependencies:

npm create saas-starter@latest my-app
cd my-app && bun run dev

To create a GitHub template repository instead, run the commands below and then rebrand it:

gh repo create my-saas-product --template stickerdaniel/saas-starter --clone
cd my-saas-product
bun install
bun run dev

Sign in with [email protected] / LocalDevAdmin123!. No external service or API key is needed until you turn a feature on. Optional features read their keys from .env.convex.local; see the environment variables. More options, including the Convex cloud dev deployment, are in Getting started.

Docs

Guide	Covers
Getting started	Local setup, rebranding, Convex cloud dev
Staying up to date	CLI copy, clone or fork, and syncing upstream
Deployment	Previews per PR, production, custom domains
Features	Auth, billing, admin, support, email, i18n
Environment variables	Every variable and where it is set
Development	Worktrees, checks, and regression guards

License

MIT