For most of the history of shipping software, a solo builder could answer one question with a single, static number: “what does this cost me a month to run?” You tallied a server, a database, a couple of SaaS subscriptions, rounded up, and you were done. The number was flat. You built to it and forgot it.
That number is now fiction.
The tools you build on stopped charging you a flat rate and started charging you by the meter. GitHub Copilot — the most common AI coding subscription on the planet — moved to usage-based billing on June 1, 2026: every plan now draws down monthly “AI Credits” pegged at one cent each, with the old automatic fallback to a cheaper model removed entirely. Anthropic now estimates the average developer burns $13 per active day in Claude Code token spend — up from $6, doubled in one quiet docs edit. Flat-rate is over, and the solo builder is the one who feels it hardest because there’s no CFO to absorb the surprise. You are the CFO, the engineer, and the one who pays.
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