The newsletters and video channels you follow, summarised in one morning email.

AmplyDigest is a full application, not a website: over 100,000 lines of code, and as many again in its own documentation.

• Architecture: a Turborepo monorepo on pnpm workspaces, with two apps and one shared package of Zod contracts. The website works as a backend-for-frontend (BFF): the browser only ever talks to it, and it calls the API with a shared secret. The API is organised in vertical slices, one folder per feature and operation, with classes wired by constructor dependency injection, and every database query scoped to the signed-in user.
• The API: TypeScript on Cloudflare Workers, with Hono. Requests are validated with Zod before they reach a handler.
• Data: Cloudflare D1 (SQLite) through Drizzle ORM, with every schema change kept as a versioned migration. The original emails in R2. Cache and rate limits in KV.
• Background work: Cloudflare Queues for every slow step, retrying what fails, with dead-letter queues for building and sending the digest. Cron Triggers run the daily digest, the clean-up, and recovery jobs that pick up anything that stalled.
• Email in: Cloudflare Email Routing delivers newsletters straight into the Worker, with no mail server. The message is parsed with postal-mime, forwarded mail is traced back to its original sender, and Workers AI turns the HTML into Markdown.
• Video: channels are found and followed through the YouTube Data API and the channels' own feeds.
• The AI: summaries are written through the Vercel AI SDK, over a list of AI providers set in configuration. The list can be reordered or changed at any time, depending on how each provider behaves and the results it gives, without touching the code. Every AI call is metered against the account's plan.
• The website: Astro 5, rendered on the server on Cloudflare, with Svelte 5, Tailwind 4, DaisyUI 5 and Bits UI.
• Accounts, payments, mail out: passwordless sign-in by emailed link through Better Auth, rate-limited per address. Payments through Polar: checkout, the customer portal, and webhooks reconciled against the real state. The morning email goes out through Maileroo.
• Quality: Vitest unit and integration tests, the integration tests running against a real SQLite database. ESLint, Prettier, and pre-commit hooks with Husky.
• Shipping: GitHub Actions, with separate staging and production. Each deploy type-checks, lints and tests, applies the D1 migrations, deploys the API, checks its health, deploys the website, and checks again.