fix(backend): pin miniaudio for mlx-audio STT (#505)

[jamiepine]

Summary

• Fresh macOS M1 installs failed to transcribe with ModuleNotFoundError: miniaudio (miniaudio is missing #505)
• mlx-audio is installed --no-deps to avoid its transformers>=5.x pin, so its transitive deps have to be declared elsewhere
• miniaudio (imported by mlx_audio.stt) was not listed in either requirements.txt or requirements-mlx.txt — the comments in both files wrongly claimed it came from another engine
• Pin it in requirements-mlx.txt (Apple Silicon only — PyTorch STT uses HF transformers and doesn't need it) and correct the stale comments

Fixes #505

Test plan

• Build macOS release via CI and confirm transcription works end-to-end on a fresh install
• Spot-check that MLX TTS (Qwen via mlx_audio.tts) still loads — unchanged path, but same --no-deps install
• Confirm no regression on Linux/Windows builds (they don't install requirements-mlx.txt)

🤖 Generated with Claude Code

---

Note

Low Risk
Low risk: only adjusts Apple-Silicon MLX dependency installation to include a missing runtime package and updates related CI comments; no application logic changes.

Overview
Fixes fresh Apple Silicon installs failing to transcribe by explicitly adding miniaudio>=1.59 to backend/requirements-mlx.txt (since mlx-audio is installed with --no-deps).

Updates the release workflow comments in .github/workflows/release.yml and requirements-mlx.txt to reflect that miniaudio is not pulled transitively and must be installed separately for mlx_audio.stt.

^{Reviewed by Cursor Bugbot for commit 791c050. Configure here.}

Summary by CodeRabbit

• Bug Fixes

  • Fixed audio library availability on Apple Silicon builds by explicitly declaring the miniaudio dependency for speech-to-text functionality.

• Chores

  • Updated dependency configuration to clarify which packages are explicitly required versus transitively included by other engines.

[coderabbitai]

📝 Walkthrough

Walkthrough

The PR adds the missing miniaudio>=1.59 dependency to the MLX-specific requirements file and updates the release workflow comment to clarify that miniaudio is explicitly pulled from requirements-mlx.txt for mlx_audio.stt support, addressing the missing dependency issue on fresh MacOS M1 installations.

Changes

Cohort / File(s)	Summary
MLX dependency configuration backend/requirements-mlx.txt	Added explicit miniaudio>=1.59 dependency for MLX audio STT support on Apple Silicon; updated comment to reflect that miniaudio is not transitively provided by other packages.
Release workflow documentation .github/workflows/release.yml	Updated MLX-only dependency installation comment to clarify that miniaudio comes from requirements-mlx.txt (for mlx_audio.stt), while remaining dependencies are pulled by other engines.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Possibly related PRs

• fix(build): pin transformers in MLX requirements to prevent 5.x upgrade #481: Both PRs modify backend/requirements-mlx.txt to change MLX-specific dependencies.
• fix(build): install mlx-audio/mlx-lm with --no-deps to bypass transformers 5.x conflict #482: Both PRs modify MLX dependency handling by updating backend/requirements-mlx.txt and release workflow logic.

Poem

🐰 A rabbit hops through dependency trees,
Finding miniaudio with ease—
MacOS M1 now can transcribe,
No missing packages to describe! 🎵

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and accurately summarizes the main change: pinning miniaudio in the MLX requirements for Speech-to-Text functionality on Apple Silicon.
Linked Issues check	✅ Passed	The code changes directly address issue #505 by adding miniaudio to requirements-mlx.txt and correcting stale comments, ensuring miniaudio is installed for Apple Silicon STT without relying on transitive dependencies.
Out of Scope Changes check	✅ Passed	All changes are directly related to resolving the miniaudio dependency issue for MLX-audio STT; no out-of-scope modifications were introduced.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/mlx-miniaudio-missing

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@backend/requirements-mlx.txt`:
- Around line 19-22: Update the comment text that currently reads "(see
.github/workflows/release.yml)." to use the preferred wording "GitHub workflow"
with a capital H for consistency; locate the comment containing
".github/workflows/release.yml" in backend/requirements-mlx.txt (the block
mentioning mlx-audio runtime deps) and change "github workflow" to "GitHub
workflow".

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 9b71aeb8-e9ef-4c10-8858-67e829f41672

📥 Commits

Reviewing files that changed from the base of the PR and between 5aa1677 and 791c050.

📒 Files selected for processing (2)

• .github/workflows/release.yml
• backend/requirements-mlx.txt

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Minor wording polish in comment block.

At Line 19, consider “GitHub workflow” wording (capital H) for consistency in docs/comments.

🧰 Tools

🪛 LanguageTool

[uncategorized] ~19-~19: The official name of this software platform is spelled with a capital “H”.
Context: ...x-audio==0.4.1` after this file # (see .github/workflows/release.yml). Most other mlx-...

(GITHUB)

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@backend/requirements-mlx.txt` around lines 19 - 22, Update the comment text
that currently reads "(see .github/workflows/release.yml)." to use the preferred
wording "GitHub workflow" with a capital H for consistency; locate the comment
containing ".github/workflows/release.yml" in backend/requirements-mlx.txt (the
block mentioning mlx-audio runtime deps) and change "github workflow" to "GitHub
workflow".