pnpm workspaces in a Next.js 16 monorepo: what the benchmark didn't measure and almost broke my CI Back in 1994, when my dad brought home an Amiga 500, I knew nothing about benchmarks. I knew that if the disk took too long to load, something was wrong. No formal metrics — just finite patience and a concrete problem staring me in the face. Thirty years later, when I published the pnpm vs npm vs yarn benchmark on my monorepo , I had clean numbers: install time, disk usage, cold cache vs warm cache. Neat. Publishable. And completely blind to what came next. Because the benchmark measured install. It didn't measure what happens when pnpm workspaces and Next.js 16 App Router collide inside a CI environment with partial cache and shared packages across workspaces. You don't see that in a bash script timed on your local machine. You see it when the Railway pipeline throws a cryptic error at 11pm and the build has been running for 18 minutes with no end in sight.…