README

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+# Pinch
+
+PIN CHannels - a simple drop-in replacement for `nix-channel --update`.
+
+Example usage, being invoked on the example "channels" file included here:
+
+    $ python3 pinch.py pin channels
+    $ python3 pinch.py update channels
+
+
+The first "pin" command will add these fields to the file:
+
+     [nixos]
+     channel_url = https://channels.nixos.org/nixos-20.03
+     git_repo = https://github.com/NixOS/nixpkgs.git
+     git_ref = nixos-20.03
+    +release_name = nixos-20.03beta1155.29eddfc36d7
+    +tarball_url = https://releases.nixos.org/nixos/20.03/nixos-20.03beta1155.29eddfc36d7/nixexprs.tar.xz
+    +tarball_sha256 = 9c1d182af2af64e5e8799e256a4a6dc1fed324ba06cb5f76c938dc63b64f0959
+    +git_revision = 29eddfc36d720dcc4822581175217543b387b1e8
+
+     [nixos-hardware]
+     git_repo = https://github.com/NixOS/nixos-hardware.git
+     git_ref = master
+    +release_name = nixos-hardware.git-1585241157-edb7199b5c4
+    +git_revision = edb7199b5c4f1db34a7253d4cabf6cf690521a92
+
+The second "update" command applies these changes to your nix channels, like `nix-channel --update` does.
+
+Advantages over nix-channel:
+
+    * Deploy the exact same channel content to multiple machines.
+    * Store your pin file in revision control for more powerful rollback mechanism than `nix-channel --rollback`.
+    * Chanel contents are verified by hash before being installed.