2025-08-25 Nix team meeting minutes #243

Development Nix
1

Monday hacking session

Usually not the best notes, because we’re already hacking and multitasking, but that won’t stop us from posting what we did write down.

You’re always welcome to join our meetings!

Attendees: @edolstra @roberth @Mic92 @lovesegfault @xokdvium @Ericson2314

[DEMO] S3 Transfer Acceleration by lovesegfault · Pull Request #13791 · NixOS/nix · GitHub

I think this should be moved to s3.cc / s3.hh.

There can be a similar pattern as FileTransfer where we have a getS3CredentialProviderCache and makeS3CredentialProviderCache. makeFileTransfer would take an const S3CredentialProviderCache & reference. getFileTransfer would call getS3CredentialProviderCache to get the reference, and DerivationBuilder (for builtins fetching) would have a little #if NIX_WITH_S3_SUPPORT to call makeS3CredentialProviderCache to make a fresh one for the forked case.

The question in my mind then is how does the underlying aws-crt-cpp cope with forking? I see these GetOrCreateStaticDefaultClientBootstrap and similar functions are also working with global mutexes, that would probably pose a similar problem.

What do you think @xokdvium?

SQLite: fsync db.sqlite-shm before opening the database by xokdvium · Pull Request #13826 · NixOS/nix · GitHub

Opened, approved

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