Spotify Open Source Projects offers a collection of high-quality software libraries and tools developed by Spotify engineers for use by the community.

zlib is a free, general-purpose, lossless data-compression library based on the 'deflate' method, used for software development and file archiving.

Roaring Bitmaps is the best software library for compressed bitsets and is used by major tech companies for data analytics.

ABI Laboratory is the best tool for API compatibility analysis and is used by software developers to maintain backward compatibility.