[other] add nix (#1076)

# Pull Request Template

## Description

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are required for this change.


Fixes # (issue)

## Type of change

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- [ ] New feature (non-breaking change which adds functionality)
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| Files            | Before      | After       | 
| -----------      | ----------- | ----------- |
| dist/build.js.   |             |             |
| dist/build.min.js|             |             |

## Checklist:

- [ ] My code follows the style guidelines of this project
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- [ ] I have made corresponding changes to the documentation
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cc @BranchMetrics/saas-sdk-devs for visibility.

Author: bredmond5

.envrc

@@ -0,0 +1 @@
+use flake

.github/workflows/deploy-qa.yml

@@ -9,7 +9,7 @@ on:
       - README.md
 env:
   BRANCH_NAME: '${{ github.event.inputs.branch_name || github.head_ref || github.ref_name  }}'
-  NODE_VERSION: 16
+  NODE_VERSION: 18
   JAVA_VERSION: 11
   JAVA_DISTRIBUTION: 'adopt'
 

.github/workflows/gate-keep.yml

@@ -2,7 +2,7 @@ name: Gate Keeping
 on:
   push:
 env:
-  NODE_VERSION: 16
+  NODE_VERSION: 18
   JAVA_VERSION: 11
   JAVA_DISTRIBUTION: 'adopt'
 

.gitignore

@@ -35,4 +35,5 @@ dist
 dev
 .nyc_output
 test-results.json
-.idea/
+.idea/
+.direnv/

flake.lock

@@ -0,0 +1,29 @@
+{
+  description = "web-branch-deep-linking-attribution flake";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
+    utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, utils }:
+    utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        nodejs = pkgs.nodejs-18_x;
+      in
+      {
+        devShell = pkgs.mkShell {
+          nativeBuildInputs = [
+            nodejs
+          ];
+          shellHook = ''
+            if [ -f $HOME/.config/bin/setup-webstorm-sdk ] && [ -f ./.idea/workspace.xml ]; then
+              $HOME/.config/bin/setup-webstorm-sdk || echo "setup-webstorm-sdk failed"
+            fi
+          '';
+        };
+        formatter = pkgs.nixpkgs-fmt;
+      }
+    );
+}