Build Log

Notes from building Nark — engineering postmortems, infrastructure decisions, and what we learned along the way.

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Cutting our Claude bill 60 percent by routing Sonnet at the worker level

A weekend audit of how we use Claude Opus, Sonnet, and Haiku across Nark's parallel agent orchestrator. Real pricing, the 35 percent tokenizer surprise, two schema regressions Sonnet shipped on day one, and the routing rule that cut coordinator burn by roughly 60 percent without losing quality.

claudeclaude codeanthropicsonnetopushaikuagent orchestrationprompt cachingcost optimizationai engineeringnark profiles

Three Ways to Handle Multi-Version npm Packages in a Static Analyzer (We Picked the Hybrid)

How Nark handles the fact that stripe v8 and stripe v21 throw different errors. A design narrative through fresh-copy forking, Profile inheritance, and per-postcondition versioning, and the maintenance liability that forced a hybrid.

static analysistypescriptsemverdesign decisionscorpus designstripenark profilespostmortem

17 Iterations to a Working PR Scanner: A Vercel Lambda Postmortem

How we shipped a working TypeScript PR scanner on Vercel Lambda after 17 iterations. Silent failures, stderr truncation order, missing Lambda primitives, and the pivot that deleted 158 lines of install logic.

vercellambdaserverlesstypescripterror handlingstatic analysisci cdgithub actionsnark profilespostmortem