Edition number 21. The React Compiler and the end of manual memoization, Marko Gaćeša on what agent-native CI/CD actually means, and the week an AI disproved an 87-year-old math conjecture.
New article: The React Compiler
What if you never had to write useMemo, useCallback, or React.memo again?
And what happens to the hundreds of manual memoization calls already sitting in your codebase?
The React Compiler does it at build time. Find out how it works, how to turn it on and what to do with your useMemos.
Podcast: Marko Gaćeša on agent-native CI/CD at scale
New episode of Señors @ Scale is out. Marko Gaćeša is Head of Product at Semaphore, the agent-native, fully open source CI/CD platform.
We get into why flaky tests are the worst enemy of fast delivery, what "agent native" CI/CD really means, migrating off GitHub Actions automatically, pricing a platform when a "minute of CI" means something different everywhere, and whether AI agents should be allowed to trigger deployments.
Watch the full episode on YouTube
Spotlight: Semaphore, CI/CD your coding agent can drive
Testing is the biggest bottleneck in the age of coding agents: your agent writes the code in minutes, then sits waiting on a slow, flaky pipeline.
Semaphore is built for exactly that world. SemAI uses skills and agents to set up and maintain your pipelines, migrate you off GitHub Actions automatically, and analyze flaky tests so your agents can debug them instead of you.
Fast, pay-as-you-go, and fully open source, so you can self-host or audit every line.
Community reads
AI and agents
Software Factories, Light and Dark by Addy Osmani — which parts of the software factory can run dark, fully automated, and which still need a human standing in the light?
Human mathematicians are being outcounterexampled by Kevin Buzzard — an AI just disproved the Jacobian Conjecture, open since 1939, the third long-standing conjecture to fall to a model in three months, all machine-verified in Lean.
Claude Code on desktop now works with the iOS Simulator by Anthropic — build and run your iOS app and the simulator opens in a panel right next to your conversation.
Software design
Symptoms of Bad Software Design by Marcos F. Lobo — rigidity, fragility, immobility, viscosity: which one is your codebase showing?
Feature-Based Architecture: Why We Organize Code by Feature by Alexander Antoniades — if your team keeps asking "where does this file go?", your codebase is organized by type, not by feature.
Engineering leadership
Lessons From Coaching 300+ Engineers and Engineering Leaders by Gregor Ojstersek — Good lessons for any leader in the industry or someone who want to join the ranks of managers.
Open source
Why I Still Write Free Open Source Software by Michele Riva — after watching profit turn his passion projects into "a nonsensical, meaningless soup of slop", he's going back to writing code for free. A refreshing read in a week where everyone is monetizing everything.
Tooling
Install dev and production side by side with app variants by Jacob Clausen — run the development, preview, and production builds of your app on the same device without uninstalling anything.
Stacked PRs explainer by Carlos Precioso — GitHub finally ships native stacked PRs, but does automating the rebase dance actually fix the problem?
Book recommendation
Tiny Experiments: How to Live Freely in a Goal-Obsessed World by Anne-Laure Le Cunff
Anne-Laure Le Cunff is a neuroscientist and the founder of Ness Labs, and this is a very nice and delightful book about learning and living a more meaningful life through curiosity.
Instead of chasing big linear goals, she makes the case for running tiny experiments: pick something you're curious about, commit to it for a set number of times, and treat the outcome as data instead of success or failure.
Meme of the week
Conferences
ZurichJS
ZurichJS is still on my list this year. Strong lineup, well-run community, and the kind of single-track conference you can actually keep up with.
Use code REACTJSBARCELONA_10 for 10% off tickets.
CityJS Athens
CityJS lands in Athens this October. Adding it here because the CityJS events are consistently worth the trip.
That's it for this one.
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