Go 1.27.1

Go 1.27.1 is a minor patch release in the Go 1.27 series, released on September 1, 2026, about two weeks after the 1.27.0 major release. It delivers a targeted set of stability fixes to the compiler, runtime, and standard library rather than any new language features.

Scope of the Release

This is a regression-fix release only. There are no new APIs, no language changes, and no compatibility breaks. According to the official Go release history, 1.27.1 includes fixes to cgo, the compiler, the runtime, the go fix command, and a set of commonly used standard library packages.

Affected Components

• cgo: Corrections around calling conventions and alignment for projects that bridge Go and C.
• Compiler: Fixes to code generation and type handling found after the 1.27.0 ship.
• Runtime: Cleanups targeting scheduler and memory-management correctness.
• go fix: Improvements so the automated migration command handles 1.27-era patterns reliably.
• Standard library: Updates to database/sql, debug/elf, encoding/json, net/http, os, simd, and simd/archsimd.

Upgrade Notes

Like any minor Go release, 1.27.1 preserves the language contract. Upgrade by updating your toolchain line or GOFLAGS, then rebuilding and rerunning your tests. Teams using reflection-heavy JSON handling, cgo, or net/http behind load balancers will want this patch promptly.

Contributors and the Go team landed these fixes quickly after the previous milestone, keeping the quarterly cadence of the 1.27 branch on track. Downloads are available from go.dev/dl.