Basic readme

Author: JoeDupuis

README.md

@@ -2,6 +2,31 @@
 
 This gem was built to replace azure-storage-blob (deprecated) in Active Storage, but was written to be Rails agnostic.
 
+## Contributing
+
+### dev environment
+
+Ensure your version of Ruby fit the minimum version in `azure-blob.gemspec`
+
+and setup those Env variables:
+
+- `AZURE_ACCOUNT_NAME`
+- `AZURE_ACCESS_KEY`
+- `AZURE_PRIVATE_CONTAINER`
+- `AZURE_PUBLIC_CONTAINER`
+
+
+A dev environment setup is also supplied through Nix with [devenv](https://devenv.sh/).
+
+To use the Nix environment:
+1- install [devenv](https://devenv.sh/)
+2- Copy `devenv.local.nix.example` to `devenv.local.nix`
+3- Insert your azure credentials into `devenv.local.nix`
+4- Start the shell with `devenv shell` or with [direnv](https://direnv.net/).
+
+### Tests
+
+`bin/rake test`.
 
 # Active Storage