Go 1.26 brings language changes, new garbage collector, improved performance, and more

Go 1.26 introduces several major language and runtime enhancements for developers. The built-in new function is now more flexible, as it accepts expressions for operands, making it simpler to specify initial variable values. This is especially helpful when populating optional fields in serialization workflows, such as with encoding/json or protocol buffers that often use pointers.

Alongside this, Go 1.26 now permits generic types to reference themselves in type parameter lists, unlocking more advanced type abstraction patterns. Developers gain further support through the fully overhauled go fix command, which now aggregates Go’s modernizers to automate updates for codebases, applying modern idioms and facilitating API migrations with a suite of fixers and a source-level inliner.

In terms of performance, the Green Tea garbage collector is now enabled by default, continuing its optimization and stability improvements from earlier experimentation. Runtime efficiency sees a boost with a roughly 30% reduction in cgo call overhead. For enhanced security, 64-bit platforms now benefit from heap base address randomization at startup, making exploitation of memory bugs in cgo harder.

Following these changes, Go 1.26 also debuts an experimental goroutine leak profile and brings further updates to the compiler, linker, bootstrap routines, and the standard library.