Code To The Moon

Software development YouTube channel specializing in Rust and LLMs.

[Code To The Moon @CodeToTheMoons]

If you’re a developer worried about AI, you’re going to love this post. Great perspective from a legendary developer

[Mitchell Hashimoto @mitchellh]

I've got an agent in a loop optimizing a renderer with the goal to minimize frame times (and tests to measure). It got times down from 88ms to 2ms and allocations down from ~150K to 500. Sounds good, right? Wrong. This is exactly why agent psychosis is a big fucking problem.

As an experiment, I rewrote the Ghostty core render state in Go, with access to identically laid out data structures as Ghostty and the exact same validation tests. I made a purposely naive renderer (simple, correct, but slow). 88ms per frame with 150,000 allocations (horrendous, lol)!

I then kickstarted a Ralph loop to bring the frame times down. I told it it can't modify input data structures or the public API or tests (they're correct), but it can do anything else it wants. It got to work.

It has worked for about 4 hours. I've spent around $350 on this experiment so far. The results?

88ms => 1.5ms
150K allocs => ~500 allocs

Incredible right? Nope.

My hand-written renderer I ported has frame times (same benchmark) of ~20us (0.020ms) and 0 allocations in the update path.

This is the problem with psychosis and lacking systems understanding. If you don't understand the system, you're going to accept that this is an incredible result. If you understand the system, you'll see better solutions immediately and can do roughly 75x better on throughput.

The people who blindly trust agent output are in the former camp. They're sheeple, overdrinking from a fountain of mediocrity.

Standard disclaimer: I use AI all the time. I like AI. The point I'm making is to not blindly accept results. Think. Analyze. Learn.

[Code To The Moon @CodeToTheMoons]

It's official. Rewrite your project in Rust, lose 5lbs. Presumably due to lower cortisol levels.

[Jarred Sumner @jarredsumner]

Mar 6: 167 lbs ( -12% )
Apr 14: 156 lbs ( -18% )
May 21: 151 lbs ( -21% )

v close to goal weight

[Let's Get Rusty 🦀 @letsgetrusty]

Insightful video here by Code to the Moon. 🦀

Check it out! 👌https://t.co/OmJ23DYHbw

#RustLang #RustRig #RustCrate

[Code To The Moon @CodeToTheMoons]

@cerebras @ml_angelopoulos @arena @SarahChieng Cool! GLM 5 when?? ���

[Josh (🦀/acc) @joshmo_dev]

rig is... rust crate of the year???

watch @CodeToTheMoons talk about the number 1 AI framework in rust: https://t.co/Zi6Rt5xiCR

[Code To The Moon @CodeToTheMoons]

Fantastic depiction of the current state of LLM assisted coding

[Andrej Karpathy @karpathy]

A few random notes from claude coding quite a bit last few weeks.

Coding workflow. Given the latest lift in LLM coding capability, like many others I rapidly went from about 80% manual+autocomplete coding and 20% agents in November to 80% agent coding and 20% edits+touchups in December. i.e. I really am mostly programming in English now, a bit sheepishly telling the LLM what code to write... in words. It hurts the ego a bit but the power to operate over software in large "code actions" is just too net useful, especially once you adapt to it, configure it, learn to use it, and wrap your head around what it can and cannot do. This is easily the biggest change to my basic coding workflow in ~2 decades of programming and it happened over the course of a few weeks. I'd expect something similar to be happening to well into double digit percent of engineers out there, while the awareness of it in the general population feels well into low single digit percent.

IDEs/agent swarms/fallability. Both the "no need for IDE anymore" hype and the "agent swarm" hype is imo too much for right now. The models definitely still make mistakes and if you have any code you actually care about I would watch them like a hawk, in a nice large IDE on the side. The mistakes have changed a lot - they are not simple syntax errors anymore, they are subtle conceptual errors that a slightly sloppy, hasty junior dev might do. The most common category is that the models make wrong assumptions on your behalf and just run along with them without checking. They also don't manage their confusion, they don't seek clarifications, they don't surface inconsistencies, they don't present tradeoffs, they don't push back when they should, and they are still a little too sycophantic. Things get better in plan mode, but there is some need for a lightweight inline plan mode. They also really like to overcomplicate code and APIs, they bloat abstractions, they don't clean up dead code after themselves, etc. They will implement an inefficient, bloated, brittle construction over 1000 lines of code and it's up to you to be like "umm couldn't you just do this instead?" and they will be like "of course!" and immediately cut it down to 100 lines. They still sometimes change/remove comments and code they don't like or don't sufficiently understand as side effects, even if it is orthogonal to the task at hand. All of this happens despite a few simple attempts to fix it via instructions in CLAUDE . md. Despite all these issues, it is still a net huge improvement and it's very difficult to imagine going back to manual coding. TLDR everyone has their developing flow, my current is a small few CC sessions on the left in ghostty windows/tabs and an IDE on the right for viewing the code + manual edits.

Tenacity. It's so interesting to watch an agent relentlessly work at something. They never get tired, they never get demoralized, they just keep going and trying things where a person would have given up long ago to fight another day. It's a "feel the AGI" moment to watch it struggle with something for a long time just to come out victorious 30 minutes later. You realize that stamina is a core bottleneck to work and that with LLMs in hand it has been dramatically increased.

Speedups. It's not clear how to measure the "speedup" of LLM assistance. Certainly I feel net way faster at what I was going to do, but the main effect is that I do a lot more than I was going to do because 1) I can code up all kinds of things that just wouldn't have been worth coding before and 2) I can approach code that I couldn't work on before because of knowledge/skill issue. So certainly it's speedup, but it's possibly a lot more an expansion.

Leverage. LLMs are exceptionally good at looping until they meet specific goals and this is where most of the "feel the AGI" magic is to be found. Don't tell it what to do, give it success criteria and watch it go. Get it to write tests first and then pass them. Put it in the loop with a browser MCP. Write the naive algorithm that is very likely correct first, then ask it to optimize it while preserving correctness. Change your approach from imperative to declarative to get the agents looping longer and gain leverage.

Fun. I didn't anticipate that with agents programming feels *more* fun because a lot of the fill in the blanks drudgery is removed and what remains is the creative part. I also feel less blocked/stuck (which is not fun) and I experience a lot more courage because there's almost always a way to work hand in hand with it to make some positive progress. I have seen the opposite sentiment from other people too; LLM coding will split up engineers based on those who primarily liked coding and those who primarily liked building.

Atrophy. I've already noticed that I am slowly starting to atrophy my ability to write code manually. Generation (writing code) and discrimination (reading code) are different capabilities in the brain. Largely due to all the little mostly syntactic details involved in programming, you can review code just fine even if you struggle to write it.

Slopacolypse. I am bracing for 2026 as the year of the slopacolypse across all of github, substack, arxiv, X/instagram, and generally all digital media. We're also going to see a lot more AI hype productivity theater (is that even possible?), on the side of actual, real improvements.

Questions. A few of the questions on my mind:
- What happens to the "10X engineer" - the ratio of productivity between the mean and the max engineer? It's quite possible that this grows *a lot*.
- Armed with LLMs, do generalists increasingly outperform specialists? LLMs are a lot better at fill in the blanks (the micro) than grand strategy (the macro).
- What does LLM coding feel like in the future? Is it like playing StarCraft? Playing Factorio? Playing music?
- How much of society is bottlenecked by digital knowledge work?

TLDR Where does this leave us? LLM agent capabilities (Claude & Codex especially) have crossed some kind of threshold of coherence around December 2025 and caused a phase shift in software engineering and closely related. The intelligence part suddenly feels quite a bit ahead of all the rest of it - integrations (tools, knowledge), the necessity for new organizational workflows, processes, diffusion more generally. 2026 is going to be a high energy year as the industry metabolizes the new capability.

[Code To The Moon @CodeToTheMoons]

@letsgetrusty Anton Putra is amazing

[Code To The Moon @CodeToTheMoons]

@dreamsofcode_io nice, very ambitious! can't wait to see how it turns out

[Code To The Moon @CodeToTheMoons]

@orhundev @ratatui_rs Move over fzf

[Code To The Moon @CodeToTheMoons]

@folken718 Ahh thanks for pointing this out, I just posted it as a regular video. I’ll look into it. First time trying this format 😎

[Code To The Moon @CodeToTheMoons]

Great line to have in the back pocket for your next interview

[Neil Zeghidour @neilzegh]

Me defending my O(n^3) solution to the coding interviewer.

[Orhun Parmaksız 👾 @orhundev]

New podcast dropped! 📢🎉🐁

With @CodeToTheMoons we talked about Ratatui, Rust, terminal code editors, AI-assisted coding & sustainable open source 🦀

▶️ Check it out here: https://t.co/oXcu3kqLTl

#rustlang #ratatui #tui #terminal #podcast #devtools

[Code To The Moon @CodeToTheMoons]

@ForrestPKnight sage advice!

[Code To The Moon @CodeToTheMoons]

@ThePrimeagen old cat

[Code To The Moon @CodeToTheMoons]

@davis7 @zeddotdev thanks for this writeup! I've been Zed-pilled lately with Cerebras but I haven't tried Composer yet, may have to give it a spin now

[Code To The Moon @CodeToTheMoons]

@joshmo_dev what, are you going to try to tell me it has fearless concurrency too??

[Code To The Moon @CodeToTheMoons]

@learnwdaniel 😱 DM sent!

[Code To The Moon @CodeToTheMoons]

@AstraKernel @chinedu_10 Maybe someone can help me with this. Why strong opinions one way or the other? Both are great and I often forget which one I’m working in tbh

[Code To The Moon @CodeToTheMoons]

@ThePrimeagen The reverb coming off that play button though…. 😉