Sprints: Add Python Packaging with Nix (#1830)

This adds a new sprint document for Python Packaging with Nix & NixOS,
outlining goals, requirements, and resources.

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Nikoś <nikoshell20@gmail.com>
Co-authored-by: Rodrigo Girão Serrão <5621605+rodrigogiraoserrao@users.noreply.github.com>

Author: 4 people

src/content/sprints/nix.md

@@ -0,0 +1,33 @@
+---
+title: "Python Packaging with Nix & NixOS"
+numberOfPeople: "8"
+pythonLevel: "Any"
+contactPerson:
+  name: "Hugo Herter"
+  email: "contact@hugoherter.com"
+  github: "hoh"
+links:
+  - title: "Nix/NixOS website"
+    url: "https://nixos.org/"
+  - title: "Nixpkgs repository"
+    url: "https://github.com/NixOS/nixpkgs/"
+  - title: "Python packaging in Nixpkgs"
+    url: "https://nixos.org/manual/nixpkgs/stable/#python"
+---
+
+Nix is a package manager and configuration language for creating reproducible
+software environments. Nixpkgs contains package definitions for a large part of
+the Python ecosystem.
+
+During this sprint, we will improve Python support in Nixpkgs by updating
+packages, fixing builds and tests, packaging missing projects, and improving
+documentation or tooling.
+
+No previous Nix experience is required. We will provide a short introduction,
+help newcomers set up their environment, and offer tasks for different
+experience levels. Familiarity with Python, Git, or packaging is helpful but not
+required.
+
+Our goals are to submit useful improvements to Nixpkgs, help new contributors
+make their first contribution, and share practical knowledge about reproducible
+Python environments.