Book: The Complete Guide to Go Programming

Also by me: Thinking in Go (2-book series) — Complete Guide to Go Programming + Hexagonal Architecture in Go

My project: Hermes IDE | GitHub — an IDE for developers who ship with Claude Code and other AI coding tools

Me: xgabriel.com | GitHub

Open the same internal/util/ folder you cleaned out when the slices package landed. The map version of that folder is still there: MapKeys[string, int] , mergeMaps , a cloneMap someone wrote because they got bitten by reference semantics once, and a mapsEqual that does the obvious thing in a slightly different way each time it appears.

Most of that file can go too. The maps package shipped in Go 1.21 alongside slices , and Go 1.23 reshaped two of its most-used functions into iterators. Eight functions cover what your helpers were doing. The migration is the same shape as the slices one: import "maps" , delete the helper, replace the call. One trap catches everyone the first time.

maps.Keys does not return []K anymore.…