diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..3550a30
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use flake
diff --git a/.gitignore b/.gitignore
index ea8c4bf..052de26 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,3 @@
 /target
+/result
+/.direnv
diff --git a/default.nix b/default.nix
deleted file mode 100644
index 83f9f14..0000000
--- a/default.nix
+++ /dev/null
@@ -1,55 +0,0 @@
-{ lib
-, naersk
-, stdenv
-, clangStdenv
-, hostPlatform
-, targetPlatform
-, pkg-config
-, libiconv
-, rustfmt
-, cargo
-, rustc
-  # , llvmPackages # Optional
-  # , protobuf     # Optional
-}:
-
-let
-  cargoToml = (builtins.fromTOML (builtins.readFile ./Cargo.toml));
-in
-
-naersk.lib."${targetPlatform.system}".buildPackage rec {
-  src = ./.;
-
-  buildInputs = [
-    rustfmt
-    pkg-config
-    cargo
-    rustc
-    libiconv
-  ];
-  checkInputs = [ cargo rustc ];
-
-  doCheck = true;
-  CARGO_BUILD_INCREMENTAL = "false";
-  RUST_BACKTRACE = "full";
-  copyLibs = true;
-
-  # Optional things you might need:
-  #
-  # If you depend on `libclang`:
-  # LIBCLANG_PATH = "${llvmPackages.libclang}/lib";
-  #
-  # If you depend on protobuf:
-  # PROTOC = "${protobuf}/bin/protoc";
-  # PROTOC_INCLUDE = "${protobuf}/include";
-
-  name = cargoToml.package.name;
-  version = cargoToml.package.version;
-
-  meta = with lib; {
-    description = cargoToml.package.description;
-    homepage = cargoToml.package.homepage;
-    license = with licenses; [ mit ];
-    maintainers = with maintainers; [ ];
-  };
-}
diff --git a/flake.lock b/flake.lock
index acc2e83..fd10261 100644
--- a/flake.lock
+++ b/flake.lock
@@ -1,48 +1,160 @@
 {
   "nodes": {
-    "naersk": {
+    "devshell": {
       "inputs": {
-        "nixpkgs": [
-          "nixpkgs"
-        ]
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
       },
       "locked": {
-        "lastModified": 1632266297,
-        "narHash": "sha256-J1yeJk6Gud9ef2pEf6aKQemrfg1pVngYDSh+SAY94xk=",
-        "owner": "nmattia",
-        "repo": "naersk",
-        "rev": "ee7edec50b49ab6d69b06d62f1de554efccb1ccd",
+        "lastModified": 1660811669,
+        "narHash": "sha256-V6lmsaLNFz41myppL0yxglta92ijkSvpZ+XVygAh+bU=",
+        "owner": "numtide",
+        "repo": "devshell",
+        "rev": "c2feacb46ee69949124c835419861143c4016fb5",
         "type": "github"
       },
       "original": {
-        "owner": "nmattia",
+        "owner": "numtide",
+        "repo": "devshell",
+        "type": "github"
+      }
+    },
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1642700792,
+        "narHash": "sha256-XqHrk7hFb+zBvRg6Ghl+AZDq03ov6OshJLiSWOoX5es=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "846b2ae0fc4cc943637d3d1def4454213e203cba",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_2": {
+      "locked": {
+        "lastModified": 1656928814,
+        "narHash": "sha256-RIFfgBuKz6Hp89yRr7+NR5tzIAbn52h8vT6vXkYjZoM=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "7e2a3b3dfd9af950a856d66b0a7d01e3c18aa249",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "naersk": {
+      "inputs": {
+        "nixpkgs": "nixpkgs_2"
+      },
+      "locked": {
+        "lastModified": 1659610603,
+        "narHash": "sha256-LYgASYSPYo7O71WfeUOaEUzYfzuXm8c8eavJcel+pfI=",
+        "owner": "nix-community",
+        "repo": "naersk",
+        "rev": "c6a45e4277fa58abd524681466d3450f896dc094",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
         "repo": "naersk",
         "type": "github"
       }
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1641687203,
-        "narHash": "sha256-W6Xrb/l1x+E+WMVLw4q5HUnNjt3x4WQFSYJtjJtopbU=",
+        "lastModified": 1643381941,
+        "narHash": "sha256-pHTwvnN4tTsEKkWlXQ8JMY423epos8wUOhthpwJjtpc=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "00acdb2aa817048fbe1f91ece18fe7de09762531",
+        "rev": "5efc8ca954272c4376ac929f4c5ffefcc20551d5",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "nixos-21.11",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1661353537,
+        "narHash": "sha256-1E2IGPajOsrkR49mM5h55OtYnU0dGyre6gl60NXKITE=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "0e304ff0d9db453a4b230e9386418fd974d5804a",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "nixpkgs_3": {
+      "locked": {
+        "lastModified": 1661353537,
+        "narHash": "sha256-1E2IGPajOsrkR49mM5h55OtYnU0dGyre6gl60NXKITE=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "0e304ff0d9db453a4b230e9386418fd974d5804a",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "nixpkgs_4": {
+      "locked": {
+        "lastModified": 1659102345,
+        "narHash": "sha256-Vbzlz254EMZvn28BhpN8JOi5EuKqnHZ3ujFYgFcSGvk=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "11b60e4f80d87794a2a4a8a256391b37c59a1ea7",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
         "repo": "nixpkgs",
         "type": "github"
       }
     },
     "root": {
       "inputs": {
+        "devshell": "devshell",
         "naersk": "naersk",
-        "nixpkgs": "nixpkgs",
+        "nixpkgs": "nixpkgs_3",
+        "rust-overlay": "rust-overlay",
         "utils": "utils"
       }
     },
+    "rust-overlay": {
+      "inputs": {
+        "flake-utils": "flake-utils_2",
+        "nixpkgs": "nixpkgs_4"
+      },
+      "locked": {
+        "lastModified": 1662001050,
+        "narHash": "sha256-tduflWLNZ6C3Xz0eUHf5Cnnfl47Vgey2NUY5ZU9f/S4=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "6f27501ff78beb62728cb292daca846fcab96c9e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
+      }
+    },
     "utils": {
       "locked": {
         "lastModified": 1637014545,
diff --git a/flake.nix b/flake.nix
index 9533e5f..af94d03 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,27 +1,53 @@
 {
-  description = "My cute Rust crate!";
+  description = "ISO7010 Twitter bot";
 
   inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-21.11";
     utils.url = "github:numtide/flake-utils";
-    naersk.url = "github:nmattia/naersk";
-    naersk.inputs.nixpkgs.follows = "nixpkgs";
+    devshell.url = "github:numtide/devshell";
+    naersk.url = "github:nix-community/naersk";
+    rust-overlay.url = "github:oxalica/rust-overlay";
   };
 
-  outputs = { self, nixpkgs, utils, naersk }:
-    let
-      cargoToml = (builtins.fromTOML (builtins.readFile ./Cargo.toml));
-    in
+  outputs = {
+    self,
+    nixpkgs,
+    utils,
+    naersk,
+    devshell,
+    rust-overlay,
+  }:
     utils.lib.eachDefaultSystem (system: let
-      pkgs = nixpkgs.legacyPackages."${system}";
-      naersk-lib = naersk.lib."${system}";
-    in rec {
-      packages."${cargoToml.package.name}" = naersk-lib.buildPackage {
-        pname = "${cargoToml.package.name}";
-        root = ./.;
-        buildInputs = [ pkgs.openssl pkgs.pkgconfig ];
+      pkgs = import nixpkgs {
+        inherit system;
+        overlays = [(import rust-overlay)];
       };
-      defaultPackage = packages."${cargoToml.package.name}";
-      hydraJobs.build = defaultPackage;
+      rust = pkgs.rust-bin.stable.latest.default;
+      # Override naersk to use our chosen rust version from rust-overlay
+      naersk-lib = naersk.lib.${system}.override {
+        cargo = rust;
+        rustc = rust;
+      };
+    in rec {
+      packages.default = naersk-lib.buildPackage {
+        pname = "iso7010-a-day";
+        root = ./.;
+        buildInputs = [pkgs.openssl pkgs.pkgconfig];
+      };
+
+      apps.default = utils.lib.mkApp {drv = packages.default;};
+
+      hydraJobs.build = packages.default;
+
+      # Provide a dev env with rust and rls
+      devShells.default = let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [devshell.overlay];
+        };
+      in
+        pkgs.devshell.mkShell {
+          packages = with pkgs; [(rust.override {extensions = ["rls"];})];
+        };
+      formatter = pkgs.alejandra;
     });
 }