grok plugin marketplace add 7etsuo/write-legible-c grok plugin install write-legible-c --trust Grok Build with Grok 4.5 is producing the most beautiful C I have ever seen come out of a model. Every function under 25 lines with one job. Nesting never past depth 2. Zero naked literals. Every failure greps to a single producing line and the happy path runs straight down the left margin. Code you can read at 2am with the pager going off. It took a standard to get there. I shipped it as a Grok Build plugin. write-legible-c gates Grok with strict C11 machine legibility every time it touches a .c or .h file. Every function is an orchestrator, a leaf, or an adapter, never a mix. A TRY macro that makes the forgotten check bug impossible to hide. An 18 item checklist the model runs before it shows you code. Clean code is a performance feature too: rewrites that cut model perceived complexity lift LLM task performance by up to 21 percent. Full 18 section standard inside.