January 31, 2026
Safe or sorry? Commenters brawl
Designing a Passively Safe API
Build it crash‑proof or just ship it? Commenters clash
TLDR: A startup is rebuilding its API to be “passively safe” so failures never double‑charge or duplicate orders. Commenters split between “isn’t this just repeat‑safe requests?” nitpicks, “use Temporal/Restate/DBOS” tool tips, and “stop over‑engineering” pushback—spotlighting the fight between bulletproof design and shipping fast.
“Passively safe” is the new buzz in API land: the author wants every request to fail gracefully so users never get double‑charged or ghost shipments. Think car crumple zones, but for software. They’re breaking a big, old system into smaller services and even adding a message broker to send emails later—only to discover new headaches, like lost messages and slow, fragile steps. The vibe: smart, ambitious, and just a little cursed.
Cue the comments cage match. One crowd waved the dictionary: “Isn’t this just idempotent?” Translation: push the button twice, get the same result. But others argued passively safe is broader—handle crashes, timeouts, and third‑party outages without making a mess, and make the final state obvious. The tool brigade stormed in next with “Don’t reinvent the wheel,” pointing to Durable Execution frameworks like Temporal, Restate, and DBOS that promise “exactly once” workflows and built‑in recovery.
Then the pragmatists dropped the mic: “This is over‑engineering. Perfect is the enemy of shipped.” The memes wrote themselves—NASA‑grade safety for shopping carts, “the shipments endpoint that won’t ship,” and yak‑shaving gifs everywhere. So we’ve got three camps: safety maximalists, tool believers, and ship‑it‑now skeptics. The only thing they agree on? Building software that never breaks is hard—and now everyone’s arguing if it should be.
Key Points
- •Augno is migrating from a monolithic API to a microservices architecture focused on passively safe endpoints.
- •Passively safe APIs ensure failures do not cause duplicate work, side effects, or unrecoverable state, completing workflows exactly once or ending in a clear terminal state.
- •A `POST /shipments` example highlights issues with external API calls outside transactions, making rollbacks impossible for foreign state changes.
- •Synchronous processing leads to slow requests (2–30 seconds), external API outages cause endpoint downtime, and requests aren’t retry-safe.
- •Introducing a message broker and background worker to send notifications asynchronously improves latency but adds new reliability concerns, including non-guaranteed message delivery.