Nix installation fails: locked nixpkgs provides Go 1.26.0 but go.mod requires 1.26.4

[tofuya]

Description

The Nix installation path currently fails to build.

Reproduction

nix profile install github:basecamp/basecamp-cli

I also reproduced the same failure via Devbox:

devbox global add github:basecamp/basecamp-cli

Error

go: go.mod requires go >= 1.26.4 (running go 1.26.0; GOTOOLCHAIN=local)

Relevant information

go.mod contains:

go 1.26.4

The flake currently pins nixpkgs revision:

400de68cd101e8cfebffea121397683caf7f5a34

In nix/package.nix, the package is built with go_1_26:

buildGoModule.override { go = go_1_26; }

In the pinned nixpkgs revision, pkgs/development/compilers/go/1.26.nix defines:

version = "1.26.0";

which matches the version reported in the build log:

running go 1.26.0

Because the build runs with GOTOOLCHAIN=local, it cannot automatically download a newer Go toolchain and the build aborts.

Expected behavior

The installation method documented in the README should build successfully:

nix profile install github:basecamp/basecamp-cli