crates.io recently started rejecting requests to https://crates.io/api/v1/crates
made by Nix: https://github.com/rust-lang/crates.io/issues/13482
This resulted in failing to download any dependencies
from crates.io with 403 error during Rust package builds.
The problem was solved in nixpkgs by switching
to CDN URL https://static.crates.io/crates
in https://github.com/NixOS/nixpkgs/pull/524985
As of writing this on 2026-05-29
the fix is on "master" branch of nixpkgs,
but not on "nixos-unstable" or "nixpkgs-unstable"
branches yet according to https://nixpk.gs/pr-tracker.html?pr=524985
so I have switched nixpkgs to "master" branch to get the problem fixed.
naersk needs a similar fix. I opened a PR for it
https://github.com/nix-community/naersk/pull/391
but because the fix is not merged yet,
switched to my PR branch in flake.nix.
Updating nixpkgs required some minor changes,
e.g. sphinx_rtd_theme has been renamed to sphinx-rtd-theme,
pthreads in Windows builds had to be moved to buildInputs to fix
"Refusing to evaluate package 'mingw_w64-pthreads-13.0.0'
in /nix/store/f78lkqnk63pd0kf52zf2wcx35p1nnalr-source/pkgs/os-specific/windows/mingw-w64/headers.nix:35
because it is not available on the requested hostPlatform"
Before I was getting
```
error: attribute 'targetPlatforms' missing
at /nix/store/dyzl40h25l04565n90psbhzgnc5vp2xr-source/pkgs/build-support/rust/build-rust-package/default.nix:162:7:
161| meta.platforms or lib.platforms.all
162| rustc.targetPlatforms;
| ^
163| };
```
This was probably an upstream issues as discussed in here
https://discourse.nixos.org/t/error-attribute-targetplatforms-missing-after-updating-inputs/54494
After this update it is fixed.
Delta Chat for Android does not support Android 4 anymore,
so there is no reason to keep using unsupported NDK.
r27 is the latest LTS version of Android NDK.
Tested:
- `nix build .#deltachat-rpc-server-arm64-v8a-android`
- `nix build .#deltachat-rpc-server-armv6l-linux`
`nix build .#deltachat-rpc-server-x86_64-android`
and
`nix build .#deltachat-rpc-server-x86-android`
still fail, but we do not build it in CI.
