error:
[stage-0 4/12] RUN nix-env -if .nixpacks/nixpkgs-ffeebf0acf3ae8b29f8c7049cd911b9636efd7e7.nix && nix-collect-garbage -d
"nix-env -if .nixpacks/nixpkgs-ffeebf0acf3ae8b29f8c7049cd911b9636efd7e7.nix && nix-collect-garbage -d" did not complete successfully: exit code: 1

View in context

unpacking 'https://github.com/NixOS/nixpkgs/archive/ffeebf0acf3ae8b29f8c7049cd911b9636efd7e7.tar.gz' into the Git cache…

error:
… while calling the 'import' builtin
at /app/.nixpacks/nixpkgs-ffeebf0acf3ae8b29f8c7049cd911b9636efd7e7.nix:3:12:
2|
3| let pkgs = import (fetchTarball "https://github.com/NixOS/nixpkgs/archive/ffeebf0acf3ae8b29f8c7049cd911b9636efd7e7.tar.gz") { overlays = [ (import (builtins.fetchTarball "https://github.com/railwayapp/nix-npm-overlay/archive/main.tar.gz")) ]; };
| ^
4| in with pkgs;
… while realising the context of a path
… while calling the 'fetchTarball' builtin
at /app/.nixpacks/nixpkgs-ffeebf0acf3ae8b29f8c7049cd911b9636efd7e7.nix:3:20:
2|
3| let pkgs = import (fetchTarball "https://github.com/NixOS/nixpkgs/archive/ffeebf0acf3ae8b29f8c7049cd911b9636efd7e7.tar.gz") { overlays = [ (import (builtins.fetchTarball "https://github.com/railwayapp/nix-npm-overlay/archive/main.tar.gz")) ]; };
| ^
4| in with pkgs;
(stack trace truncated; use '--show-trace' to show the full, detailed trace)
error: Failed to open archive (Source threw exception: error: unable to download 'https://github.com/NixOS/nixpkgs/archive/ffeebf0acf3ae8b29f8c7049cd911b9636efd7e7.tar.gz': HTTP error 404
response body:
404: Not Found)

happens in all my deployments