Turborepo is an open source task orchestration tool for JavaScript and TypeScript monorepos, acquired by Vercel in 2021, which speeds up builds, tests and checks by only re-running what has changed.
It reads the dependencies between the packages in the repository, runs tasks in the right order and in parallel where possible, and caches their results. If a package has not changed, its build is not re-run: the result is fetched from the cache, locally or from a cache shared between developers and CI. On a large monorepo, continuous integration time drops significantly.
Its main competitor is Nx, more complete but more opinionated. Turborepo bets on a minimal configuration that fits onto an existing repository. For very large, multi-language monorepos, tools such as Bazel take over.
Why it matters when hiring
Turborepo belongs to developer tooling: it is a topic for a Developer Experience profile, a Platform Engineer or a front-end Tech Lead. The tool is quick to pick up; the real skill is structuring a monorepo (package boundaries, dependencies, remote cache). Ask the candidate what slowed down their team's CI and what they did about it.