Przemek Mroczek (@mroczekdev) header
Przemek Mroczek (@mroczekdev) profile picture

Backend engineer, 13 yrs · ex-PayPal · Built Facebook Data Analyzer (500+ ⭐). Now building mental math app in public and talking to our future AI overlords

Warszawa, Polska
Joined January 2024
Photo by Przemek Mroczek (@mroczekdev)Photo by Przemek Mroczek (@mroczekdev)Photo by Przemek Mroczek (@mroczekdev)Photo by Przemek Mroczek (@mroczekdev)Photo by Przemek Mroczek (@mroczekdev)Photo by Przemek Mroczek (@mroczekdev)Photo by Przemek Mroczek (@mroczekdev)Photo by Przemek Mroczek (@mroczekdev)Photo by Przemek Mroczek (@mroczekdev)
🤢 can we just gatekeep a little bit? please
BBC: Hablaremos con nuestro experto en seguridad de BBC respecto a la vulnerabilidad de PHP. El experto en seguridad: No sabía que PHP existía hasta ayer en la mañana.
9
Cooked this parody of Blame it on Boogie with Opus 5.5, Suno, remotion, three.js and some creative hacking. Don't blame me, blame the agent
1
38
Everything is Rust Now | music video Suno 6 + Opus 5.5 motion graphics
2
56
I’m upping my p(doom)
this is actually just straight up good shit. genuine art. what is happening
36
Przemek Mroczek retweeted
this is actually just straight up good shit. genuine art. what is happening
269
531
221
7,802
639,700
I feel bad for developers who went to Rails World 2026. You paid $699 to hear from creator of Rails that he is no longer excited about it. Although ai rewriting the game arguments make sense. It feels like people bought tickets for their career funeral #dhh #rubyonrails
2
70
Vibe coders doing security checks on their ai slop apps. LGTM
1
161
Someone needs to override ⁠method_missing⁠ in Ruby to just raise a ⁠NotImplementedError⁠, banishing it forever and ushering in the Age of Aquarius
98
Watching Ed Zitron is very unhealthy, all rage not much substance. If you try to say a bad thing about him the comments explode with attacks. It’s almost like he owns some tech PR company and clip farm
57
Can’t wait to try it tomorrow and see what’s all the fuss about
I had early access to 5.6/Sol for ~month. Sol is my default. It is faster, plans/judges just as good as Fable, and I think produces better overall work. I’ll reach for Fable still for highly targeted debug or performance work with clear reward functions. A cheeky way I describe Sol vs Fable to my friends is that Sol is a charismatic, efficient, talented coworker you’re jealous of. Fable is a genius recluse that is brilliant at its fixations but doesn’t go out, doesn’t date, and you don’t want to hang out with them much lol. Fable is undefeated at highly targeted debug/security/performance goals. It’s a sight to behold and I was never able to get Sol to push as hard in this category. I’ll keep using it for this. Sol is better or comparable at everything else, in my experience. Give it a shot, it’s hard to describe but it’s just more enjoyable to work with. (Disclaimer I have no financial ties to either lab, wasn’t paid for any of this.)
69
Thanks to Fable 5 I added some cool features to the mental math app on ios. The bottom sheets are nice improvement over lack of customization of challenges. #buildinpublic
52
AI will kill LinkedIn. If you add more superficiality to superficial social network, the results will be crazy
43
Small update. I am back to the building apps game after last classes at uni. Mental math app (new demo):
34
Joke that explains proof by contradiction Student: What is proof by contradiction? Teacher: I think you know. Student: If I knew, I wouldn’t be asking. And I am asking, so that means that I don’t know. Teacher: Ah, so you did know
36
My Cursor subscription when I haven’t used it since Fable 5 was banned.
41
Hot take: The 2004 "Rails blog in 15 minutes" screencast is still one of the most effective pieces of developer marketing ever made
46
Prediction (let's revisit in a couple years): AI will trigger a wave of Rails/Django rewrites toward more performant stacks: Go, a TypeScript framework(Next, TanStack Start), or even Rust. The cost of a rewrite is about to drop a lot.
51
Hot take from Louis Rossmann. I might finally decide to pull the trigger on camera and start streaming building in public and learn how to handle feeling awkward on videos.
36