[RenanGBarreto]

Prevent PS5-unsafe automatic ISA-L compression

🤔 Why?

• ISA-L output can trigger PS5 hardware-inflater failures for some games, causing crashes or kernel panics even when software verification passes.

🔧 What changed

• auto now selects zlib-ng, then zlib; it never selects ISA-L.
• Explicit --compression-backend isal remains available, with a clear warning and issue reference.
• Updated CLI help, README guidance, worker fallback behavior, and regression coverage.

🧪 How to test

• ./run-tests.sh
• Confirm default packing emits no ISA-L warning.
• Confirm explicit ISA-L packing emits warning linking to issue [BUG] ISA-L backend (auto-selected) produces PFSC blocks that the PS5 hardware inflater rejects #132.

💬 Notes

• Existing images and explicit backend choices remain supported.

Closes #132

[github-code-quality]

Code Coverage Overview

Languages: Python

Python / code-coverage/pytest

The overall line coverage in commit d63f2ee in the bugfix-isa-l branch remains at 68%, unchanged from commit 31da542 in the main branch.

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_{Updated October 03, 2026 11:16 UTC}