Our own builds

A file is visible only to the person who uploaded it and to administrators. That one rule is enforced on every request, in one place in the code, and never only by hiding things in the interface.

What it guarantees

• The same answer for every refusal. A file you may not see, a file that doesn't exist and a malformed address all return the same “not found”, so the system never confirms that a file is there.
• No double effects. A double click, a browser retry or a resubmitted form never creates a second copy. Each action carries a key, and a repeat gets the first result back.
• Uploads that can't half-happen. Size is limited while the file streams in, the type is read from the file's own first bytes, and a failed upload leaves nothing behind.
• Nothing worth stealing in the database. Passwords are hashed with argon2id, and sessions are stored only as hashes, so a leaked database hands out no live sign-ins.
• Quiet logs. Passwords, cookies and request bodies are removed before anything is logged.

How it was built

The requirements, the architecture, the security rules and the test scenarios were written first: the happy path, the failures, the edge cases and the bottlenecks. Every technical choice is recorded with the alternative that was rejected and why. The application was then built against that specification one module at a time, from setup to collaboration, with unit tests and end-to-end browser tests.

Next.js, TypeScript, PostgreSQL, Drizzle, Zod, argon2id, Vitest, Playwright