Add nix flake

flake.nix

@@ -0,0 +1,46 @@
+{
+    description = "Tool to simplify secure shell connections over AWS simple systems manager.";
+
+    inputs = {
+      nixpkgs.url = "github:NixOS/nixpkgs?ref=nixpkgs-unstable";
+      utils.url = "github:numtide/flake-utils";
+    };
+    outputs = { self, nixpkgs, utils }: {
+      devShell = self.defaultPackage;
+      defaultPackage.x86_64-darwin =
+        with import nixpkgs { system = "x86_64-darwin"; };
+        let
+          awssh = pkgs.python310Packages.buildPythonPackage rec {
+            pname = "awssh";
+            version = "1.1.0";
+            doCheck = false;
+            propagatedBuildInputs = with pkgs.python310Packages; [
+              setuptools
+              wheel
+              boto3
+              docopt
+              schema
+              ];
+            src = (pkgs.fetchFromGitHub {
+              owner = "cisagov";
+              repo = "awssh";
+              rev = "v1.1.0";
+              sha256 = "sha256-4b2VBFUQye4wTvuagPwEImLwkUO4Dk5hvOYW+eg8OGA=";
+          });};
+        in
+          pkgs.python310Packages.buildPythonPackage rec {
+            pname = "awssh";
+            version = "1.1.0";
+            src = ./.;
+            propagatedBuildInputs = with pkgs.python310Packages; [
+              wheel 
+              setuptools
+              docopt
+              schema
+              boto3
+            ];
+          };
+    };
+  }
+
+