lsix

@bobvanderlinden there is already a fix in nixpkgs (https://github.com/NixOS/nixpkgs/commit/5f0a7cded718d0092229ba078cb7f0f7733bf636). I just ported it to stable so as soon as the channel has been updated by hydra it will be fixed...

I have pushed a revised implementation that has significantly better performances compared to the first one. However, it still is an order of magnitude slower than the original one for...