Hookline
An open source webhook inspector: point any service at a Hookline URL, watch requests arrive, replay them and diff payloads.
client
—
role
Author and maintainer
year
2025
stack
Go · SvelteKit · SQLite
01 / problem
Debugging webhooks usually means a tunnel, a print statement and a lot of guessing. The hosted inspectors keep your payloads on someone else’s server, which most of my clients could not allow.
02 / approach
Hookline is a single Go binary with an embedded SQLite file and a SvelteKit UI. It records every request, shows headers and bodies side by side, replays any request to a local port and diffs two payloads field by field. It runs on a laptop or on the cheapest cloud server you can rent.
03 / outcome
Hookline passed 4,000 GitHub stars in its first year and has had pull requests from 120 contributors. Two of my client teams now run it in staging as their default webhook target.
4.2k
GitHub stars
120
Contributors
