posts
- The mutant was killed after it switched a real GPU
A hand-written mutant made my Go CLI skip -proxy. Its test failed on cue, after a real model load that then kept a benchmark off a GPU for almost half an hour.
- The lock map deleted a mutex someone was waiting on
A Go transfer by Flash-Next Q2_0 scored 100 and passed 6 of 6 failure-path tests. One cleanup line let a retried key move the money twice.
- llama.cpp's MoE cache wants gigabytes and long prompts
On a 24 GB RTX 3090, llama.cpp's MoE expert cache read long prompts up to 85% faster, did nothing for a Q8 model, and left a 2-4x gap to Strata.
- Measuring OpenTelemetry Overhead Without Fooling Yourself
What OpenTelemetry costs a Spring Boot app in MiB and CPU per order, and the proofs each test cell needed before its number counted.
- Your GraalVM Version Is the Other Number
Which GraalVM to build native images with in 2026, what the free edition lacks, and why the image tag shows the JDK version, not GraalVM's.
- The test rig was the unsafe part
A suite that tells six coding agents to run rm -rf and docker system prune had a throwaway HOME and bwrap --unshare-net. Neither isolated what it needed to.
- The secret filter made my security test pass
A guard test passed on the old code in one agent. Its secret mask had eaten the marker that meant 'ran'. Then the fix passed for a different wrong reason.
- The fix was in five agents. The sixth never called it.
A guard fix was unit-tested in both implementations and probed on one agent. Per-agent end-to-end cases found the one agent whose hook never ran it.
- The 3090 unlock is real. Where it lands is the catch
gpu_unlock lifted my RTX 3090's BF16 GEMM from 74.9 to 128 TFLOPS. My daily 27B in llama.cpp got 0.7% faster at short context. Here's where the rest went.
- Tests that could not fail
I broke my agent guard on purpose so its 'ask' meant 'allow'. Two new tests still passed on another layer's say-so; a third passed on the old code too.