gpac: add ffmpeg support & refactor

[thesn10]

This is my first contribution so i am happy to take advice ^^

• Adds FFmpeg support to gpac
• Adds gpac_nightly package that tracks HEAD
  • This is needed, because the gpac team recommends using nightly over stable
• Adds myself as a maintainer

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• Nixpkgs 25.11 Release Notes (or backporting 25.05 Nixpkgs Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
• NixOS 25.11 Release Notes (or backporting 25.05 NixOS Release notes)
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md, pkgs/README.md, maintainers/README.md and other contributing documentation in corresponding paths.

---

Add a 👍 reaction to pull requests you find important.

[thesn10]

nixpkgs-review result

Generated using nixpkgs-review.

Command: nixpkgs-review pr 424904 --extra-nixpkgs-config '{ withFullDeps = true; }'
Commit: 12f8f0a79a4990345d3e134b254a5cac44698d3d

---

x86_64-linux

✅ 1 package built:

• gpac_nightly

[thesn10]

@mgdelacroix can you review?

[thesn10]

@mdaniels5757 can you review?
The original maintainer seems to be inactive and i want to adopt this package

[mdaniels5757]

Welcome, and thanks for this contribution! I'm sorry it took so long for it to be reviewed.

I've left some comments/suggestions inline. Some additional overall things:

• The merge commits should not be present in this PR. Probably the easiest way to fix it is to run git rebase -i $(git merge-base HEAD upstream/master)
• The nix fmt commit should be combined with the "add ffmpeg support & refactor" commit. One way to do this would be to leave the nix fmt commit out of the rebase command above, and edit the "add ffmpeg support & refactor" commit in the rebase. Then when editing the commit you can run the formatter.
• Commits "2.4-unstable-2025-07-11 -> 2.4-unstable-2025-09-07" and "2.4-unstable-2025-09-07 -> 2.4-unstable-2025-10-26" should be combined into one. You can choose to squash the second into the first in the rebase command above.

[thesn10]

@mdaniels5757 Thanks for your detailed review and for taking time to actually help me implement this and show me how to integrate the update script! It was very helpful for me as a newbie ^^
I implemented your suggestions, can you take a look again?

[mdaniels5757]

Looks good to me! I'm happy you found my suggestions helpful: I had worried they could be sort of overwhelming...

[mdaniels5757]

One thing I should note, actually: I don't think that this should be updated on a daily basis. Nixpkgs just isn't built to handle that. The unstable build should be advanced on more of a "the update bot triggered, and the changes made are substantial" basis, for the most part (absent e.g. a bug that is fixed in upstream, in which case a manual update would make sense).

[thesn10]

Okay great, but how do i actually get this PR merged?
Do i also need a review from the maintainer? The problem is he is inactive.

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/prs-already-reviewed/2617/2632

[RossComputerGuy]

nixpkgs-review result

Generated using nixpkgs-review.

Command: nixpkgs-review pr 424904
Commit: 62d9589af359626a841841e8f991bf9bd57cc1bf

---

aarch64-linux

✅ 1 package built:

• gpac-unstable

[RossComputerGuy]

Approved automatically following the successful run of nixpkgs-review.