Package Hazkey blocked on Swift 6.1 packaging

[hasundue]

Summary

I investigated packaging upstream 7ka-Hiira/hazkey in this flake as a replacement for fcitx5-mozc on the desktop host.

The main blocker is Swift: upstream Hazkey currently requires Swift 6.1 for the server component, while the nixpkgs in this repo currently provides Swift 5.10.1.

Current integration points in this repo

• Package exports live under packages/ and are wired through flake.nix via pkgs.callPackage.
• Desktop fcitx5 config is in configs/home/desktop/fcitx5.nix.
• The current IM addon is pkgs.fcitx5-mozc, and the configured engine is mozc.
• configs/home/desktop/waybar.nix assumes the Japanese engine name is mozc for its JP status indicator.

Upstream Hazkey notes

• Repository: https://github.com/7ka-Hiira/hazkey
• The current repo bundles fcitx5-hazkey, hazkey-server, and hazkey-settings.
• Upstream installs the fcitx5 addon/input method as hazkey, so config changes here would likely need to switch from mozc to hazkey.
• Upstream uses git submodules for at least dictionary storage and llama.cpp, so fetchSubmodules = true is likely required.
• AI/Zenzai support is a real requirement for this effort, so a non-AI fallback is not the target.

What I tried

1. Investigated packaging shape

I used Warashi's older fcitx5-hazkey packaging as prior art:

• https://github.com/Warashi/nix-fcitx5-hazkey

That package is useful for dependency/layout ideas, but it targets the older split repository and is not a drop-in solution for current upstream hazkey.

2. Verified local nixpkgs state

Observed locally:

• swift = 5.10.1
• swiftpm and swiftpm2nix are available

Baseline validation of this repo succeeded:

• nix flake check

3. Probed upstream Hazkey build requirements

Relevant upstream findings:

• hazkey-server/Package.swift declares // swift-tools-version: 6.1
• hazkey-server depends on SwiftPM packages including AzooKeyKanaKanjiConverter and swift-protobuf
• The fcitx5 input method metadata installs hazkey.conf under both addon and inputmethod paths

4. Tested the official Swift 6.1 Linux tarball

I fetched and probed the official Swift 6.1 Ubuntu toolchain tarball.

Good news:

• the compiler binary itself can start under Nix once given the expected runtime libraries

Bad news:

• the toolchain is not a clean drop-in fit for nixpkgs here
• after fixing earlier runtime issues (ar, curl, ncurses), SwiftPM still failed on distro ABI expectations like libxml2.so.2
• current nixpkgs provides different ABI/library layouts (for example, current libxml2 here exposes libxml2.so.16)

So the official Ubuntu Swift 6.1 tarball is not a robust solution for this flake.

5. Looked for a Nix-native Swift 6 source

I checked:

• public GitHub code/repo search for community flakes/overlays
• current nixpkgs issue/PR trail
• the Swift 6 tracking discussion on NixOS Discourse

Findings:

• there is active Swift 6 packaging work in the Nix community
• I could not find a public, consumable Linux Swift 6 flake/overlay/branch/PR that can be dropped into this repo today

Blocker

Hazkey packaging is currently blocked on a public Nix-native Swift 6 toolchain source that is usable on Linux.

Without that, we cannot package current upstream Hazkey with AI/Zenzai support in a way that is consistent with this repo's Nix packaging approach.

Recommended next step

Resume this work when one of these is available:

1. a public nixpkgs branch/PR exposing Swift 6.x for Linux
2. a community-maintained Nix overlay/flake that provides a compatible Swift 6 toolchain
3. a Nix-native local packaging effort for Swift 6 that avoids Ubuntu tarball ABI mismatches

Once unblocked, the implementation path in this repo should be:

1. add a local Hazkey package under packages/
2. export it from flake.nix
3. replace fcitx5-mozc with Hazkey in configs/home/desktop/fcitx5.nix
4. update configs/home/desktop/waybar.nix to recognize hazkey instead of mozc
5. validate the package and Home Manager evaluation

Upstream

• Issue #343210 — nixpkgs Swift 6 packaging tracker
• Issue #405893 — nixpkgs Swift 6 packaging tracker

Search

Also check for new PRs matching: swift 6, author:reckenrode swift in NixOS/nixpkgs.

[hasundue]

[github-actions]

Issue monitor found new signals for Swift 6 packaging for Hazkey:

• Tracked issue updated: NixOS/nixpkgs#343210 - Update request: swift 5.8 → 6 (updated 2026-04-12T17:55:10Z)
  Update request: swift 5.8 → 6 NixOS/nixpkgs#343210
• New matching PR: NixOS/nixpkgs#242666 - Discussion: The future of SDKs on Darwin
  Discussion: The future of SDKs on Darwin NixOS/nixpkgs#242666
• New matching PR: NixOS/nixpkgs#308342 - Replace opencflite with CoreFoundation from Swift
  Replace opencflite with CoreFoundation from Swift NixOS/nixpkgs#308342
• New matching PR: NixOS/nixpkgs#326073 - Package request: swiftly
  Package request: swiftly NixOS/nixpkgs#326073
• New matching PR: NixOS/nixpkgs#343210 - Update request: swift 5.8 → 6
  Update request: swift 5.8 → 6 NixOS/nixpkgs#343210
• New matching PR: NixOS/nixpkgs#343877 - Update request: swift 5.8 → 6.0
  Update request: swift 5.8 → 6.0 NixOS/nixpkgs#343877
• New matching PR: NixOS/nixpkgs#379859 - swiftpm: swift-test errors with libIndexStore.so cannot open shared object file
  swiftpm: swift-test errors with libIndexStore.so cannot open shared object file NixOS/nixpkgs#379859
• New matching PR: NixOS/nixpkgs#405893 - Tracking issue: Darwin updates for 25.11
  Tracking issue: Darwin updates for 25.11 NixOS/nixpkgs#405893
• New matching PR: NixOS/nixpkgs#422471 - Update Request: anki 25.02.5 → 25.07
  Update Request: anki 25.02.5 → 25.07 NixOS/nixpkgs#422471
• New matching PR: NixOS/nixpkgs#471058 - Build failure: mpv-unwrapped versionCheckHook fails (darwin)
  Build failure: mpv-unwrapped versionCheckHook fails (darwin) NixOS/nixpkgs#471058
• New matching PR: NixOS/nixpkgs#483584 - Build failure: swift on darwin
  Build failure: swift on darwin NixOS/nixpkgs#483584

Generated by .github/workflows/issue-monitor.yml.

[hasundue]

Issue monitor found new signals for Swift 6 packaging for Hazkey:

• Matching PR updated: NixOS/nixpkgs#264091 - llvmPackages_*.stdenv: use top-level libc++ on Darwin (updated 2024-10-17T07:59:57Z)
  llvmPackages_*.stdenv: use top-level libc++ on Darwin NixOS/nixpkgs#264091
• Matching PR updated: NixOS/nixpkgs#346043 - darwin: change the SDK pattern, update the SDKs, and update source releases (updated 2025-02-07T00:44:51Z)
  darwin: change the SDK pattern, update the SDKs, and update source releases NixOS/nixpkgs#346043
• Matching PR updated: NixOS/nixpkgs#346947 - swift: fix build with the new SDK pattern (updated 2024-10-31T14:27:02Z)
  swift: fix build with the new SDK pattern NixOS/nixpkgs#346947
• Matching PR updated: NixOS/nixpkgs#350395 - doc: update platform documentation for the new Darwin SDK pattern (updated 2024-11-04T20:43:57Z)
  doc: update platform documentation for the new Darwin SDK pattern NixOS/nixpkgs#350395
• Matching PR updated: NixOS/nixpkgs#353893 - xcbuild: look in native toolchain when /usr/bin is in path (updated 2025-02-07T12:30:27Z)
  xcbuild: look in native toolchain when /usr/bin is in path NixOS/nixpkgs#353893
• Matching PR updated: NixOS/nixpkgs#360207 - swift: source darwin-sdk-setup.bash (updated 2025-01-09T00:26:21Z)
  swift: source darwin-sdk-setup.bash NixOS/nixpkgs#360207
• Matching PR updated: NixOS/nixpkgs#398727 - darwin.libcxx: (╯°□°）╯︵ ┻━┻ (updated 2025-09-22T01:50:12Z)
  darwin.libcxx: (╯°□°）╯︵ ┻━┻ NixOS/nixpkgs#398727
• Matching PR updated: NixOS/nixpkgs#400745 - Refactor mas package + update from 1.9.0 release -> 2.1.0 release (updated 2026-03-09T10:41:52Z)
  Refactor mas package + update from 1.9.0 release -> 2.1.0 release NixOS/nixpkgs#400745
• Matching PR updated: NixOS/nixpkgs#445094 - apple-sdk: clean up and improve compatibility with Swift (updated 2025-10-24T08:23:42Z)
  apple-sdk: clean up and improve compatibility with Swift NixOS/nixpkgs#445094
• Matching PR updated: NixOS/nixpkgs#445095 - cc-wrapper: always include libc++ in the search path (updated 2026-01-05T23:09:25Z)
  cc-wrapper: always include libc++ in the search path NixOS/nixpkgs#445095

Generated by .github/workflows/issue-monitor.yml.

[github-actions]

Issue monitor found meaningful updates for Swift 6 packaging for Hazkey:

Tracked issue updated: NixOS/nixpkgs#343210

reckenrode (the primary nixpkgs Swift packager) posted several significant progress updates since last reported:

1. 2026-05-30 — Swift 6.1.1 is now building using nixpkgs LLVM infrastructure. A prerequisite PR (#407738, llvmPackages_19 → llvmPackages_21) has since been merged.

2. 2026-06-04 — Pushed a public WIP branch (swift-update) with the update work-in-progress, including LLVM 19→20 bump, compiler-rt updates, and rewritten SwiftPM integration.

3. 2026-01-02 — Swift 6.2.3 is bootstrapping on Darwin using C++. The stdlib is being split into its own derivation.

4. Ongoing discussions about vendoring SwiftPM dependencies and Linux support (acknowledged as needing work after Darwin is stable).

Impact: The primary Swift 6 blocker for Hazkey packaging (NixOS/nixpkgs#343210) now has active, public progress from the lead packager. Linux support is still explicitly listed as pending ("I have a Linux builder, but haven't tried it yet"), but the Darwin bootstrap is working and the packaging approach is crystallizing.

Suggested action: Revisit Hazkey packaging when Swift 6.1+ is available on Linux in nixpkgs. Monitor #nixpkgs-swift:matrix.org for real-time updates.