i have this error when i build at your server gives me this

#7 [stage-0 3/8] COPY .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix

Jan 14 23:10:14

#7 DONE 0.0s

Jan 14 23:10:14

Jan 14 23:10:15

Jan 14 23:10:15

#8 [stage-0 4/8] RUN nix-env -if .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix && nix-collect-garbage -d

Jan 14 23:10:15

#8 0.133 unpacking 'https://github.com/NixOS/nixpkgs/archive/5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.tar.gz'; into the Git cache...

Jan 14 23:10:15

Jan 14 23:10:38

#8 23.44 installing '5148520bfab61f99fd25fb9ff7bfbb50dad3c9db-env'

Jan 14 23:10:38

Jan 14 23:10:38

#8 23.59 error:

Jan 14 23:10:38

#8 23.59 … while calling the 'derivationStrict' builtin

Jan 14 23:10:38

#8 23.59 at <nix/derivation-internal.nix>:34:12:

Jan 14 23:10:38

#8 23.59 33|

Jan 14 23:10:38

#8 23.59 34| strict = derivationStrict drvAttrs;

Jan 14 23:10:38

#8 23.59 | ^

Jan 14 23:10:38

#8 23.59 35|

Jan 14 23:10:38

#8 23.59

Jan 14 23:10:38

#8 23.59 … while evaluating derivation '5148520bfab61f99fd25fb9ff7bfbb50dad3c9db-env'

Jan 14 23:10:38

#8 23.59 whose name attribute is located at /nix/store/lgcjj6s23v2203zyihsd0j26wh1saj0c-source/pkgs/stdenv/generic/make-derivation.nix:300:7

Jan 14 23:10:38

#8 23.59

Jan 14 23:10:38

#8 23.59 … while evaluating attribute 'passAsFile' of derivation '5148520bfab61f99fd25fb9ff7bfbb50dad3c9db-env'

Jan 14 23:10:38

#8 23.59 at /nix/store/lgcjj6s23v2203zyihsd0j26wh1saj0c-source/pkgs/build-support/trivial-builders/default.nix:88:7:

Jan 14 23:10:38

#8 23.59 87| inherit buildCommand name;

Jan 14 23:10:38

#8 23.59 88| passAsFile = [ "buildCommand" ]

Jan 14 23:10:38

#8 23.59 | ^

Jan 14 23:10:38

#8 23.59 89| ++ (derivationArgs.passAsFile or []);

Jan 14 23:10:38

#8 23.59

Jan 14 23:10:38

#8 23.59 (stack trace truncated; use '--show-trace' to show the full, detailed trace)

Jan 14 23:10:38

#8 23.59

Jan 14 23:10:38

#8 23.59 error: attribute 'dev' missing

Jan 14 23:10:38

#8 23.59 at /app/.nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix:19:13:

Jan 14 23:10:38

#8 23.59 18| '')

Jan 14 23:10:38

#8 23.59 19| gcc postgresql_16.dev python39

Jan 14 23:10:38

#8 23.59 | ^

Jan 14 23:10:38

#8 23.59 20| ];

Jan 14 23:10:38

#8 23.59 Did you mean doc?

Jan 14 23:10:38

Jan 14 23:10:38

#8 ERROR: process "/bin/bash -ol pipefail -c nix-env -if .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix && nix-collect-garbage -d" did not complete successfully: exit code: 1

Jan 14 23:10:38

Jan 14 23:10:38

-----

Jan 14 23:10:38

> [stage-0 4/8] RUN nix-env -if .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix && nix-collect-garbage -d:

Jan 14 23:10:38

23.59

Jan 14 23:10:38

23.59 (stack trace truncated; use '--show-trace' to show the full, detailed trace)

Jan 14 23:10:38

23.59

Jan 14 23:10:38

23.59 error: attribute 'dev' missing

Jan 14 23:10:38

23.59 at /app/.nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix:19:13:

Jan 14 23:10:38

23.59 18| '')

Jan 14 23:10:38

23.59 19| gcc postgresql_16.dev python39

Jan 14 23:10:38

23.59 | ^

Jan 14 23:10:38

23.59 20| ];

Jan 14 23:10:38

23.59 Did you mean doc?

Jan 14 23:10:38

-----

Jan 14 23:10:38

Jan 14 23:10:38

Dockerfile:8

Jan 14 23:10:38

-------------------

Jan 14 23:10:38

6 |

Jan 14 23:10:38

7 | COPY .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix

Jan 14 23:10:38

8 | >>> RUN nix-env -if .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix && nix-collect-garbage -d

Jan 14 23:10:38

9 |

Jan 14 23:10:38

10 |

Jan 14 23:10:38

-------------------

Jan 14 23:10:38

ERROR: failed to solve: process "/bin/bash -ol pipefail -c nix-env -if .nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix && nix-collect-garbage -d" did not complete successfully: exit code: 1

Jan 14 23:10:38

Jan 14 23:10:38

Error: Docker build failed

why is that !!