Update flake and expose beta/nightly in `packages`

flake.lock

@@ -2,11 +2,11 @@
   "nodes": {
     "flake-utils": {
       "locked": {
-        "lastModified": 1609246779,
-        "narHash": "sha256-eq6ZXE/VWo3EMC65jmIT6H/rrUc9UWOWVujkzav025k=",
+        "lastModified": 1614513358,
+        "narHash": "sha256-LakhOx3S1dRjnh0b5Dg3mbZyH0ToC9I8Y2wKSkBaTzU=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "08c7ad4a0844adc4a7f9f5bb3beae482e789afa4",
+        "rev": "5466c5bbece17adaab2d82fae80b46e807611bf3",
         "type": "github"
       },
       "original": {
@@ -17,15 +17,17 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1609079092,
-        "narHash": "sha256-KhyKfxBHtZlAgudpZ0EJVzeuqROjKfVOwj8j0cuhU50=",
-        "path": "/nix/store/5pmay8rdvgw5ml1xi6189xhdbygc850k-source",
-        "rev": "2f47650c2f28d87f86ab807b8a339c684d91ec56",
-        "type": "path"
+        "lastModified": 1617325113,
+        "narHash": "sha256-GksR0nvGxfZ79T91UUtWjjccxazv6Yh/MvEJ82v1Xmw=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "54c1e44240d8a527a8f4892608c4bce5440c3ecb",
+        "type": "github"
       },
       "original": {
-        "id": "nixpkgs",
-        "type": "indirect"
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "type": "github"
       }
     },
     "root": {

flake.nix

@@ -5,10 +5,11 @@
   '';
 
   inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs";
     flake-utils.url = "github:numtide/flake-utils";
   };
 
-  outputs = { self, nixpkgs, flake-utils, ... }@inputs: let
+  outputs = { self, nixpkgs, flake-utils }: let
     inherit (nixpkgs) lib;
 
     overlay = import ./.;
@@ -47,8 +48,19 @@
       lib.mapAttrs' (version: comps: {
         name = "rust-${lib.replaceStrings ["."] ["-"] version}";
         value = comps.rust;
-      }) pkgs.rust-bin.stable // {
+      }) pkgs.rust-bin.stable //
+      lib.mapAttrs' (version: comps: {
+        name = "rust-nightly-${version}";
+        value = comps.rust;
+      }) (removeAttrs pkgs.rust-bin.nightly [ "2018-11-01" "2020-09-12" ]) // # FIXME: `rust` is not available.
+      lib.mapAttrs' (version: comps: {
+        name = "rust-beta-${version}";
+        value = comps.rust;
+      }) (removeAttrs pkgs.rust-bin.beta [ "2018-11-09" ]) // # FIXME: `rust` is not available.
+      {
         rust = packages.rust-latest;
+        rust-nightly = packages.rust-nightly-latest;
+        rust-beta = packages.rust-beta-latest;
       };
 
     checks = let