Sini

building apps for fun after dark | scaling to $10k for a start | fan of scalable distributed systems | senior staff engineer

[Sini @sinibuilds]

I've worked in tech for 20+ years... and I have a confession...

I was never a good coder.

I did it all: infrastructure, consulting, devops, architecture, developer — at banks, startups, media - and built massive distributed sytems in an org moving £521 million a day.

And still, coding was still my weak point.

I was slow and never a friend of frameworks and patterns.

What I was good at: making systems work.

Connecting the pieces. Building reliable systems. Architecting for availability and scale. Keeping things running at scale at crazy high availability.

How could we otherwise move that £521 million a day...

Then AI coding tools came along and something clicked.

AI fills the exact gap I've had my entire career. It handles the coding for me that never really mastered.

I bring the systems thinking, the infra, the architecture.

Together? It's the most productive I've ever been.

So now, after 20+ years of building for corporations, I'm finally building for myself.

Small tools. Useful products. Things people actually want.

And maybe — if enough people show up — I'll finally get to solve the scaling problems I actually love.

Building in public starts now. Follow along.

[Sini @sinibuilds]

@tibo_maker this looks more like a full rebuild

Q: Hey Claude, fix the basement!
A: rm -rf level2, level1, level...

[Sini @sinibuilds]

Anyways, fixed.

[Sini @sinibuilds]

Better to double check API docs before building...

Opus hallucinated that @RevenueCat uses HMAC-SHA256 instead of a simple secret token.

[Sini @sinibuilds]

Now I'm burning more Opus tokens to fix it

Isn't it ironic?

[Sini @sinibuilds]

By day, I build software where a single bug costs real money. Twenty years of it.

By night, I'm a complete beginner. Never shipped an indie product. Don't know how to get my first user. Learning distribution from zero — the one thing 20 years in tech never taught me.

Both true at once. And the gap between them is uncomfortable.

Staying in the lane where I'm known and respected would be easier. But building a real product alone, in 1-2 hours a day, never added up — until AI coding made it possible.

So now I'm a beginner again.

No success stories yet. Just a starting line.

If you're senior somewhere and quietly itching to start over — follow along.

[Sini @sinibuilds]

@jackfriks How do you make sure that existing features don’t break when adding something new? Could also ask what kind of test you use?

[Sini @sinibuilds]

@josefandre_ @lukenguyen_me @alexcooldev Yes they had.

[Sini @sinibuilds]

Weird AI hallucination?

Claire Code? @claudeai

This is now repeating...

[Sini @sinibuilds]

For sure I overcomplicate things.

A Java backend, NodeJS for frontend & iPhone app too.

Am I crazy?

[Sini @sinibuilds]

@Nicolascole77 @dickiebush Social

[Sini @sinibuilds]

I don't wanna learn TypeScript yet.

So I'll stick to the plain old Java.

I know TS is coming for me... :)

[Sini @sinibuilds]

I started to use the Claude mobile app to remote coding on my machine at home while I commute.

It’s fun and also far away from a good coding interface.

But at least I make some progress instead of idling.

[Sini @sinibuilds]

Will add an iPhone app too

[Sini @sinibuilds]

Building a tool that gives me quick overviews of every new video from my YouTube subscriptions.

So I only watch what’s actually worth my time.

[Sini @sinibuilds]

@asaio87 @averycode @HackerResidency Whenever it's happening, I'd love to go too!

[Sini @sinibuilds]

@tibo_maker I’m in!

[Sini @sinibuilds]

I like when I ask @OpenAICodexCli to fix a bug I found, and it talks about it like it discovered the bug itself.

[Sini @sinibuilds]

I probably said this already: I’ll start working on side projects.

Well I already did, it is just hard to find enough time for it.

For now it’s for fun and to build tiny useful tools for myself.

[Sini @sinibuilds]

@marclou What do you use QStash for? I’m genuinely interested in how it is useful for you.

[Sini @sinibuilds]

@AntonioVissoni @alexcooldev Yes. That worked for me as well. No sugar, as low on carbs as I can (still eating vegs, but no pasta, rice, bread and so on…)