CleanBuild

CleanBuild is a build automation tool designed to produce reproducible, clean builds by enforcing isolated build environments and strict dependency management. It emphasizes determinism, avoiding artifacts from previous runs, and ensuring that each build starts from a well-defined baseline.

The project emerged from the challenge of flaky software builds caused by environmental drift and ad-hoc dependencies. CleanBuild advocates containerization and sandboxing to isolate the build process from the host system, using techniques such as chroot-like environments or container runtimes to guarantee isolation.

Architecturally, CleanBuild centers on a declarative build manifest, a content-addressable cache, and a pluggable set of language adapters. It resolves a dependency graph, computes a build plan, and executes steps in a controlled sandbox. The system records all inputs—source, dependencies, toolchain, environment variables—so that a given plan is reproducible.

In practice, developers declare their build configuration and optional constraints; CleanBuild fetches dependencies, compiles, tests, and packages within the clean sandbox, leveraging caching to reuse unchanged results. It integrates with common continuous integration pipelines and supports incremental builds, parallel execution, and artifact signing.

CleanBuild has been adopted by various open-source projects and some enterprises seeking reproducible builds. It is part of a broader ecosystem of build tools that aim to reduce environment-related failures and improve auditability. Critics point to initial setup complexity and potential performance overhead, but supporters argue that the reproducibility and portability benefits outweigh these costs.