Six reasons your monorepo CI got slower this quarter

Originally published on dxcore.dev . I've been building a CI scheduler — an internal tool that grew out of getting tired of watching my own Turborepo monorepo CI get slower on GitHub Actions. The pattern across teams that have been at it for ten years is consistent enough to write down. Shopify got 95% of their monolith CI runs under 18 minutes, down from 45 — but only after it had silently grown the other direction for years. Slack cut their average end-to-end build from around 10 minutes to ar