Show IH: CheckAPI – API monitoring that catches silent failures, not just HTTP 200
Hey IH đź‘‹
I'm Sewon, a solo developer from Seoul. I just launched CheckAPI — an API monitoring
tool with a specific focus on silent failures.
The problem I kept running into
Standard monitors check HTTP status codes. But what about this scenario:
- Your API returns 200 OK âś…
- But the response body is empty, malformed, or contains {"error": "db_connection_failed"} ❌
Your monitor says everything is fine. Your users are experiencing a broken product.
This is a silent failure — and it's more common than you'd think.
What CheckAPI does differently
Response body validation with three modes:
- Keyword — must be present ("status":"ok") or absent ("error")
- Regex — pattern matching for structured responses
- JSON Path — coming soon
Plus the usual stuff: 5 alert channels (Email, Slack, Telegram, Discord, Webhook),
public status pages, SSL expiry alerts, response time tracking.
Why I built this (beyond the technical reason)
UptimeRobot restricted commercial use on free plans in December 2024. A lot of indie
hackers got caught off guard. CheckAPI's free plan (10 monitors) has zero commercial
restrictions — forever.
##Stack
Open source (MIT): github.com/JEONSEWON/CheckAPI
##Pricing
Free → $5 → $15 → $49/mo
Live at: checkapi.io
Would love feedback from this community — especially around what monitoring features
you actually use vs. what sounds good on paper.
Catching semantic failures is the part most API monitors skip, and it's usually where the painful bugs hide. The hard part is letting people express "200 but wrong payload, empty result, stale data" without turning setup into a test framework. Curious how CheckAPI handles assertions and false positives, that's where these tools usually win or lose.
This is a really interesting angle — those “everything looks fine but it’s not” failures are the worst to catch.
Curious if most people come to this after something breaks, or if you’re seeing teams actually monitor this proactively?
Congrats on the launch, Sewon.
Silent failures are a nightmare for developers, so catching what's actually inside the response body is a great focus.
I am also building something that solves a "silent" frustration for parents called WordyKid.
It is a tool that lets parents snap a photo of any physical worksheet or book and instantly turns it into a language game.
It is all about making sure the learning actually happens instead of just "completing" the task.
Good luck with the growth!
🙏
Thank you! Really appreciate it.
"Completing the task" vs "actually learning" — that's exactly the same problem
I'm solving on the API side. The surface looks fine, but nothing real is happening underneath.
WordyKid sounds genuinely useful. Snapping a worksheet and turning it into a game
is the kind of thing parents will love. Good luck with it! 🚀