7777e06a added a dependancy on playwright which wouldn't run in
nix-shell without extra configuration.
the simpliest configuration (used in this commit) required a more
recent version of nixpkgs unstable. unfortunately these more recent
versions introduce a 'system limit for file watchers reached' bug in
storybook's server when run on linux. This can be mitigated by
manually increasing the watcher limit.
attempts to fix the playwright nixpkgs dependancies to different
versions still introduced the bug
hopefully the bug will disapear in newer releases of nixpkgs unstable
start with a nix boilerplate for svelte that supports reproducible
builds
taken unedited from https://github.com/knarkzel/sveltekit-nix
c444859e97fb13393ad6e295132412bbea044e32