AI made writing code cheap. Attune (YC X25) is betting the slow part is now everything after - starting with builds. Its whole pitch fits in one word you type before your command: hurry.
There is a specific kind of dead time every programmer knows. You hit build. You wait. You check Slack, refill your coffee, lose the thread of what you were doing. Multiply that across a day, a team, a quarter, and the waiting becomes one of the largest and least-measured costs in software. Attune, a San Francisco company in Y Combinator's X25 batch, is built entirely around erasing it.
The company's promise is four words long - "Faster builds, zero effort" - and its product is close to that terse. Instead of running cargo build, you run hurry cargo build. That word, hurry, is the whole interface. Behind it, Attune pulls the expensive levers that normally require a specialist to set up: incremental compilation, remote execution, and distributed caching. The company says the result is up to 20x faster builds.
Attune's thesis is a claim about where software is heading. As AI tools let developers produce code faster than ever, the constraint stops being how quickly you can write and starts being everything downstream: building, testing, shipping. If typing is no longer the slow part, then the slow part is the machine turning that typing into something that runs.
This is a subtle place to plant a flag. Slow builds don't trigger an alert. No dashboard turns red. The cost is spread thin across every engineer's day, which is exactly why it goes unaddressed for years. Attune is wagering that the tax is real, large, and about to get more painful as AI cranks up the volume of code flowing into build systems.
Build speed is not an unsolved problem. Tools like Bazel and Buck2 can make builds dramatically faster. The catch is the price of entry: adopting them typically means migrating your project to a new build system, rewriting build files, and learning a new configuration language. For a working team with deadlines, that migration is often the reason fast builds never happen. The alternative - throwing bigger, more expensive hardware at the problem - has an obvious ceiling.
Attune's answer is to make speed a subtraction rather than an addition. There is no migration, no new config language, no build files to rewrite. You keep the commands you already run and add a prefix. That design choice - "zero effort" - is less a marketing line than the company's core go-to-market strategy: the fastest tool nobody adopts is the one that demands a migration first.
Attune was founded in 2025 by Xin Ding and Eliza. The pair didn't come to build systems as a hunch - they worked together for three years at FOSSA, where Eliza was Head of Engineering and Xin was Head of Product, helping customers analyze and secure their build pipelines. Eliza, previously at Google, brings programming-languages and compiler expertise. Xin brings roughly a decade in developer-tools product, most recently as VP of Product at Teleport (YC S15), where he scaled a SaaS offering to eight figures in annual recurring revenue.
That background matters for a company selling to engineers, an audience with a finely tuned detector for tools built by people who haven't done the work. Attune's founders spent years watching teams bleed time to slow compiles - and watching them decline the painful migrations that would have fixed it. The product is, in a sense, the fix they wished those customers could have taken without the pain.
Today, Attune works for Rust - fitting, since the company's own tooling is written in Rust. The plan is to expand across the ecosystems where builds hurt most. The order is a product decision in itself: each new target is a fresh integration, and covering them all is the difference between a Rust utility and a build-acceleration platform.
Alongside the accelerator, Attune maintains an open-source project for fast and secure Linux package publishing. It handles APT repositories for Debian and Ubuntu, supports self-hosted or managed hosting, and signs the repository index locally so your signing keys never leave your machine. It's written in Rust and licensed Apache 2.0, with incremental index rebuilds for quick package additions and removals.
The structure here is classic open core. A free Community Edition earns credibility with individual developers and small teams; an Enterprise Edition targets security- and compliance-conscious organizations that need self-hosted or on-premises deployment and priority support. In developer tools, trust is the currency - and giving away something genuinely useful is how you earn the right to sell the rest.
Attune sits in a crowded but fragmented corner of developer tools - somewhere between the heavyweight build systems that demand migration and the narrow caching utilities that solve one slice of the problem. Its wedge is the refusal to make you change anything. Whether that's enough to build a durable business depends on how much of the "post-AI" thesis comes true: if the volume of AI-generated code keeps climbing, the pressure on everything downstream of writing climbs with it.
For now it's two or three people, a $130K check, and one very specific claim - that your builds are too slow, and that fixing it should cost you exactly one word. It's a narrow bet. Narrow bets, made by people who know the terrain, are often the ones worth watching.