Radar · Go · Archive · Week 33 · Aug 11 – 17, 2025

go1.25.0 released

Worth knowingecosystem

What changed: Go 1.25 was released, bringing container‑aware GOMAXPROCS, the testing/synctest package, experimental GC, experimental encoding/json/v2, and more.
Production impact: The source does not say.
Try it: Run go version to confirm you are on 1.25 and explore the new packages in the standard library.
Source: go.dev/doc/devel/release#go1.25.0

Understand it, then run it

Run it now

Todaygo

// This program demonstrates the current GOMAXPROCS value.
// The new container‑aware behavior is not yet available in Go 1.27.1,
// so we simply print the value returned by runtime.GOMAXPROCS(0).
package main

import (
	"fmt"
	"runtime"
)

func main() {
	// runtime.GOMAXPROCS(0) returns the current maximum number of CPUs
	// that can execute simultaneously. In a container this is the
	// container's CPU quota if the feature is enabled.
	max := runtime.GOMAXPROCS(0)
	fmt.Printf("GOMAXPROCS: %d\n", max)
}

What it printed when we ran it on Go 1.27.1

GOMAXPROCS: 2

Run sends this program (for Solidity, the contract and its tests) to our own sandbox, where it is compiled and run once, with no network, and what it printed or the test report comes back here. Nothing is kept. Runs are counted per visitor for the day so everyone gets a turn; the details are on the legal page.

Written by gpt-oss-20b from the linked source · claims checked against the sources · archive, not individually reviewed