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● Field note · January 2026 · 7 min read · Frollie

Just‑in‑time development — when "we need a voucher system" becomes a one‑hour job.

The promotion was on Friday. We needed a voucher system by Wednesday. Five years ago that's a four‑week sprint, a backlog ticket, a JIRA epic. In our setup it became a one‑hour job between two meetings. Here's what that actually looks like and why it changes how a small ops team thinks about software.

Draft in progress

What this field note will cover.

  • The setup — a category manager runs into me at the office, mentions a voucher requirement for Friday's launch.
  • The hour — what I actually did: spec the data model in a paragraph, point Claude Code at the existing checkout flow, ask for the smallest reasonable cut, run it, ship to staging, hand to QA, push to prod.
  • The principle — software is no longer a capacity problem. It's a clarity problem. The bottleneck is the spec, not the build.
  • What this means for ops teams — the "we'll get to it next quarter" answer has died. If a request can be specified clearly, it can be built today.
  • The downside — the discipline this requires. Without spec rigour, JIT development becomes JIT mess. The cost of a bad voucher system in production is higher than the cost of not building it.

— Full note coming. The voucher anecdote is a real one, lifted from January.

— Lucas, January 2026 · field note from Frollie