use nix flake & remove legacy shell.nix

flake.lock

@@ -0,0 +1,43 @@
+{
+  "nodes": {
+    "import-cargo": {
+      "locked": {
+        "lastModified": 1594305518,
+        "narHash": "sha256-frtArgN42rSaEcEOYWg8sVPMUK+Zgch3c+wejcpX3DY=",
+        "owner": "edolstra",
+        "repo": "import-cargo",
+        "rev": "25d40be4a73d40a2572e0cc233b83253554f06c5",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "import-cargo",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1606667422,
+        "narHash": "sha256-NhCeG6NpetMWkflygIn6vHipuxFbrKzlFScr8+PONYQ=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "3c72bb875e67ad1bce805fe26a8a5d3a0e8078ed",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-20.09",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "import-cargo": "import-cargo",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,70 @@
+{
+    description = "Converts audio files";
+
+    inputs = {
+        nixpkgs.url = github:NixOS/nixpkgs/nixos-20.09;
+        import-cargo.url = github:edolstra/import-cargo;
+    };
+
+    outputs = { self, nixpkgs, import-cargo }:
+        let
+            inherit (import-cargo.builders) importCargo;
+        in {
+            defaultPackage.x86_64-linux =
+                with import nixpkgs { system = "x86_64-linux"; };
+                stdenv.mkDerivation {
+                    name = "audio-conv";
+                    src = self;
+
+                    nativeBuildInputs = [
+                        # setupHook which makes sure that a CARGO_HOME with vendored dependencies
+                        # exists
+                        (importCargo { lockFile = ./Cargo.lock; inherit pkgs; }).cargoHome
+
+                        # Build-time dependencies
+                        cargo
+                        rustc
+                        pkg-config
+                    ];
+
+                    buildInputs = [
+                        gst_all_1.gstreamer
+
+                        # needed for opus, resample, ...
+                        gst_all_1.gst-plugins-base
+
+                        # needed for flac
+                        gst_all_1.gst-plugins-good
+                    ];
+
+                    buildPhase = ''
+                        cargo build --release --offline
+                    '';
+
+                    installPhase = ''
+                        install -Dm775 ./target/release/audio-conv $out/bin/audio-conv
+                    '';
+                };
+
+            devShell.x86_64-linux =
+                with import nixpkgs { system = "x86_64-linux"; };
+                stdenv.mkDerivation {
+                    name = "audio-conv";
+                    buildInputs = [
+                        cargo
+                        rustc
+                        rustfmt
+                        rust-analyzer
+
+                        pkg-config
+                        gst_all_1.gstreamer
+
+                        # needed for opus, resample, ...
+                        gst_all_1.gst-plugins-base
+
+                        # needed for flac
+                        gst_all_1.gst-plugins-good
+                    ];
+                };
+        };
+}

shell.nix

@@ -1,22 +0,0 @@
-let
-    nixpkgs = import <nixpkgs> {};
-in
-    with nixpkgs;
-    stdenv.mkDerivation {
-        name = "audio-conv";
-        buildInputs = [
-            cargo
-            rustc
-            rustfmt
-            rust-analyzer
-
-            pkg-config
-            gst_all_1.gstreamer
-
-            # needed for opus, resample, ...
-            gst_all_1.gst-plugins-base
-
-            # needed for flac
-            gst_all_1.gst-plugins-good
-        ];
-    }