Node.js 27.0.0-Alpha.0.0.0 (Alpha)

Node.js 27.0.0-alpha.0.0.0 moves V8 from 14.6 to 15.6.75.13, drops the bundled FIPS provider build, requires OpenSSL 3 or later, and upgrades OpenSSL sources to 4.1.0 and npm to 12.1.0. The release notes also describe a new default heap limit (half of physical memory, clamped to 256 MB–4 GB, with Buffer memory counted), a serialization format older releases cannot read, and a 65-second http keepAliveTimeout default. These last items were not independently verified. Teams should test memory settings and mixed-version messaging early.