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Notes on backend and data engineering, and the systems behind them.
No logins, no tracking, no data collection. I can't believe I have to say that. Long live the handmade web.
If you find these articles useful, I'm glad. There's nothing to pay for. If you're a builder, email me your work. I'd love to see it.
Swadhin's Greatest Hits
Recent Posts
Own Your Namespace: Building a Private DNS Root at Home
OpenInternet in practice: a private root, a .swadhin TLD, authoritative servers in your closet, and the honest limits of running your own corner of DNS.
OpenCode wrote 125,000 loose Git objects into my home directory and never committed once
20% of my disk free, 2% CPU, 29% RAM, and the machine still hung. Btrfs metadata was 93% full and 125,000 of the files were loose Git objects from an agent snapshot layer.
Designing data pipelines that stay cheap
Efficient pipeline design is mostly a set of decisions about bytes scanned, work repeated, and failures survived. Here is how I reason through them, with the arithmetic shown.
Designing an API for 100,000 requests a second
The requirement was 100K rps. The work was arithmetic, a stateless tier, a cache that absorbs most of it, and a long list of things that break before the CPU does.
Flare: self-hosted webmail for my own domain
I built Flare to run mail for my own domain without an IMAP server. Astro on a Worker, Turso for state, Resend or Maileroo for delivery, webhooks for inbound.
A filesystem event log in SQLite
Point it at a folder and every create, edit, rename and delete lands in a local database. Undo, replay, fork and diff, without git in the way.