# Tested Kimi K3 for Coding (2026) > Source: > Published: 2026-07-20 14:01:33+00:00 The new model **Kimi K3** was released this week, and it is claimed to be **near-frontier** level quality similar to Fable and GPT. I decided to try it out and see if it could **optimize** my **Rust program**. I felt a less specific task, like "optimize this function somehow" was a good test. I set up Kimi K3 in **OpenCode**, and made a copy of my program directory so that I could throw away the changes made easily. I directed a prompt to the function I wanted optimized. I had spent a fair amount of time optimizing this function, and I did not seem to be making much progress on my own. Kimi K3 had **2 recommendations**, and I decided to have it pursue the `SWAR` optimization—SIMD Within a Register. With `SWAR` , a single 64-bit value is treated as 8 eight-bit values—so we can handle 8 `u8` values (single-byte) at once. Kimi K3 took about **15 minutes** for the task, and it completed it perfectly. I found the optimization sped up the program by 2%. So Kimi K3 both **decided** on an appropriate optimization, and **implemented** it with **no errors**—it seems to me that Kimi K3 could well be a frontier-level model as advertised. It cost about $1 for the tokens on OpenRouter.