The Go Blog

Go 1.23 is released

Dmitri Shuralyov, on behalf of the Go team
13 August 2024

Today the Go team is happy to release Go 1.23,
which you can get by visiting the download page.

If you already have Go 1.22 or Go 1.21 installed on your machine,
you can also try go get [email protected] in an existing module.
This will download the new toolchain and let you begin using it
in your module right away. At some later point, you can follow up
with go get [email protected] when you’re ready to fully switch to Go 1.23
and have that be your module’s minimum required Go version.
See Managing Go version module requirements with go get
for more information on this functionality.

Go 1.23 comes with many improvements over Go 1.22. Some of the highlights include:

Language changes

• Range expressions in a “for-range” loop may now be iterator functions,
  such as func(func(K) bool).
  This supports user-defined iterators over arbitrary sequences.
  There are several additions to the standard slices and maps
  packages that work with iterators, as well as a new iter package.
  As an example, if you wish to collect the keys of a map m into a slice
  and then sort its values, you can do that in Go 1.23 with slices.Sorted(maps.Keys(m)).

  Go 1.23 also includes preview support for generic type aliases.

  Read more about language changes and iterators
  in the release notes.

Tool improvements

• Starting with Go 1.23, it’s possible for the Go toolchain to collect usage and breakage
  statistics to help understand how the Go toolchain is used, and how well it is working.
  This is Go telemetry, an opt-in system. Please consider opting in to help us keep Go
  working well and better understand Go usage.
  Read more on Go telemetry in the release notes.
• The go command has new conveniences. For example, running go env -changed makes it easier to
  see only those settings whose effective value differs from the default value, and
  go mod tidy -diff helps determine the necessary changes to the go.mod and go.sum files
  without modifying them.
  Read more on the Go command in the release notes.
• The go vet subcommand now reports symbols that are too new for the intended Go version.
  Read more on tools in the release notes.

Standard library improvements

• Go 1.23 improves the implementation of time.Timer and time.Ticker.
  Read more on timer changes in the release notes.
• There are a total of 3 new packages in the Go 1.23 standard library: iter, structs, and unique.
  Package iter is mentioned above.
  Package structs defines marker types to modify the properties of a struct.
  Package unique provides facilities for canonicalizing (“interning”) comparable
  values.
  Read more on new standard library packages
  in the release notes.
• There are many improvements and additions to the standard library enumerated
  in the minor changes to the library
  section of the release notes.
  The “Go, Backwards Compatibility, and GODEBUG” documentation
  enumerates new to Go 1.23 GODEBUG settings.
• Go 1.23 supports the new godebug directive in go.mod and go.work files to
  allow separate control of the default GODEBUGs and the “go” directive of go.mod,
  in addition to //go:debug directive comments made available two releases ago (Go 1.21).
  See the updated documentation on Default GODEBUG Values.

More improvements and changes

• Go 1.23 adds experimental support for OpenBSD on 64-bit RISC-V (openbsd/riscv64).
  There are several minor changes relevant to Linux, macOS, ARM64, RISC-V, and WASI.
  Read more on ports in the release notes.
• Build time when using profile-guided optimization (PGO) is reduced, and performance
  with PGO on 386 and amd64 architectures is improved.
  Read more on runtime, compiler, and linker in the release notes.

We encourage everyone to read the Go 1.23 release notes for the
complete and detailed information on these changes, and everything else that’s
new to Go 1.23.

Over the next few weeks, look out for follow-up blog posts that will go in more depth
on some of the topics mentioned here, including “range-over-func”, the new unique package,
Go 1.23 timer implementation changes, and more.

Thank you to everyone who contributed to this release by writing code and
documentation, reporting bugs, sharing feedback, and testing the release
candidates. Your efforts helped to ensure that Go 1.23 is as stable as possible.
As always, if you notice any problems, please file an issue.

Enjoy Go 1.23!