{"action":"opened","issue":{"url":"https://api.github.com/repos/datakurre/nix-build-pack-docker/issues/1","labels_url":"https://api.github.com/repos/datakurre/nix-build-pack-docker/issues/1/labels{/name}","comments_url":"https://api.github.com/repos/datakurre/nix-build-pack-docker/issues/1/comments","events_url":"https://api.github.com/repos/datakurre/nix-build-pack-docker/issues/1/events","html_url":"https://github.com/datakurre/nix-build-pack-docker/issues/1","id":127013259,"number":1,"title":"Overriding a python 3.5 expression","user":{"login":"danielegozzi","id":7228,"avatar_url":"https://avatars.githubusercontent.com/u/7228?v=3","gravatar_id":"","url":"https://api.github.com/users/danielegozzi","html_url":"https://github.com/danielegozzi","followers_url":"https://api.github.com/users/danielegozzi/followers","following_url":"https://api.github.com/users/danielegozzi/following{/other_user}","gists_url":"https://api.github.com/users/danielegozzi/gists{/gist_id}","starred_url":"https://api.github.com/users/danielegozzi/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/danielegozzi/subscriptions","organizations_url":"https://api.github.com/users/danielegozzi/orgs","repos_url":"https://api.github.com/users/danielegozzi/repos","events_url":"https://api.github.com/users/danielegozzi/events{/privacy}","received_events_url":"https://api.github.com/users/danielegozzi/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2016-01-16T09:39:54Z","updated_at":"2016-01-16T09:39:54Z","closed_at":null,"body":"I'm trying to use your technique for building a container from scratch based on a nix expression, just as  this repo nix-build-pack-docker does.\r\nI wanted to use python 3.5, but I noticed that the default settings in nixpkgs imply a dependency from TCL, TK and X11.\r\nI don't seem to be able to override effectively the default settings, since I obtain a container with two different python 3.5 closures: both one with my overrides and a default one as a dependency from python3.5m-setuptools.\r\n  \r\nMy expression, instead of your pyramid.nix:\r\n```\r\nwith import <nixpkgs> {\r\n  config = ({\r\n    packageOverrides = pkgs: rec {\r\n      python35 = pkgs.python35.override {\r\n        tcl = null;\r\n        tk = null;\r\n        libX11 = null;\r\n        xproto = null;\r\n        db = null;\r\n        gdbm = null;\r\n      };\r\n    };\r\n  });\r\n};\r\n\r\npython35.buildEnv.override {\r\n    python = python35;\r\n    extraLibs = [ python35Packages.pytz ];\r\n    ignoreCollisions = true;\r\n}\r\n```\r\n\r\nThe resulting dependency graph:\r\n![pytz nix](https://cloud.githubusercontent.com/assets/7228/12371693/a01b2f94-bc3c-11e5-9db6-4d30c8aacdc7.png)\r\n\r\nThis may be a bug in the buildPythonPackage or wrapPython functions, but I'm not really familiar with nix, so I thought of asking you before submitting an issue to nixpgs.\r\n"}}