Im.won

Building useful software from Seoul 🇰🇷 | Founder @ Axiom Technologies | | Shipping in public

[Im.won @imwon_dev]

Both features are free on all plans.

Gating AI behind a paywall felt wrong.
It should just work from day one.

If you're building API-heavy products:
→ https://t.co/GIE9Thrd1E

What would you want AI to do
in your monitoring alerts? 👇

#buildinpublic #indiehackers #SaaS

[Im.won @imwon_dev]

Got paged at 2am for an API outage.

Opened Slack:

❌ https://t.co/belPcIPI2g — DOWN

That was it.

Took 23 minutes to find the cause.
Users couldn't check out the whole time.

So I added AI. 🧵

[Im.won @imwon_dev]

Two things that were actually hard:

1. Claude wrapping JSON in markdown fences
→ had to strip before json.loads()
→ caused silent failures in prod
→ ironic for a silent failure detector

2. SSRF protection
→ block localhost, private IPs, AWS metadata
→ DNS-resolve hostnames before the request
→ https://t.co/iBFiDEwqJM can resolve to 192.168.1.1

Small details. Both hit production.

[Im.won @imwon_dev]

3/ SEO cleanup

→ sitemap: 3 pages → 14 pages
→ removed render-blocking Google Fonts
→ switched to next/image (WebP + lazy load)
→ 2 new blog posts from GSC keyword data

---

distribution without discoverability is just noise.

still giving away 10 free Pro plans.
drop a reply if you want in.

→ https://t.co/UkZUQhloVF

#buildinpublic #indiehackers #devtools #seo

[Im.won @imwon_dev]

this week I stopped adding features.

instead I asked: how do people find CheckAPI
before they know they need it?

here's everything I shipped 👇

[Im.won @imwon_dev]

2/ AEO — optimizing for AI search engines

SEO is for Google.
AEO is for ChatGPT, Perplexity, Claude.

most founders haven't done this yet.

what I did:
→ allowed 9 AI crawlers in robots.ts
→ created /llms.txt for AI engines
→ added FAQ JSON-LD to all 10 blog posts
→ rewrote H2s as questions

goal: when someone asks ChatGPT
"best API monitor with a free plan"
CheckAPI shows up in the answer.

[Im.won @imwon_dev]

rewrote my homepage copy in 2 hours based on a stranger's comment.

someone on Indie Hackers told me:

"HTTP 200 OK does not mean your product is working.
that should be your headline."

before: "API monitoring with Silent Failure Detection"
after: "Catch silent API failures before your users do"

one comment. two hours. live.

the old headline described what CheckAPI is.
the new one describes what happens if you don't use it.

also moved this to the top of the page:

"login returns 200. but the token is missing.
your monitor says ✅ healthy."

one line beats three paragraphs every time.

---

this reminded me that feedback changes products faster
than any roadmap ever will.

so I'm doing something about it.

giving away 10 free Pro plans ($15/mo) for 1 month.

one condition — use it. then tell me what's broken,
what's missing, what you'd never give up.

drop a reply with one line about what you'd use it for.
picking 10 this week.

→ https://t.co/UkZUQhloVF

#buildinpublic #indiehackers #devtools

[Im.won @imwon_dev]

still at early MRR. still solo. still shipping.

→ https://t.co/GIE9Thrd1E

#buildinpublic #indiehackers #devtools

[Im.won @imwon_dev]

two things happened today while building CheckAPI.

[Im.won @imwon_dev]

2/ posted a full product update on Indie Hackers.

wrote about what changed since the last post:
— 4-layer Silent Failure Detection (JSONPath, Regex, Keyword, Header)
— homepage rebuilt around "free for commercial use"
— what building in public actually did for the product

link in - https://t.co/eHDz1eHA9O

[Im.won @imwon_dev]

CheckAPI is free for commercial use. forever.

no "upgrade to monitor more than 1 endpoint"
no "alerts only on paid plan"
10 monitors, all 5 alert channels, JSON Path assertions — free.

full launch post on IH: [https://t.co/0CAShlxsAn]
or just try it: https://t.co/UkZUQhloVF

#buildinpublic #indiehackers #devtools #saas

[Im.won @imwon_dev]

I got a comment on Indie Hackers that changed everything.

"Your biggest advantage is that you allow commercial use for free.
That should be your headline."

so I rebuilt CheckAPI around that insight.

just posted the full story 👇

[Im.won @imwon_dev]

after that IH comment, I went back to the drawing board.

rebuilt the homepage.
rewrote the messaging.
fixed bugs I'd been ignoring.

205 commits. 7 months. one piece of feedback that reframed everything.

this is what building in public actually does for you.