updated readme

README.md

@@ -1 +1,14 @@
 # carapace-selfupdate
+
+Simple self-update mechanism to install nightly/stable releases.
+
+[![asciicast](https://asciinema.org/a/692857.svg)](https://asciinema.org/a/692857)
+
+
+- Relies on [curl](https://curl.se) to avoid additional dependencies.
+- Installs to [GOBIN](https://pkg.go.dev/cmd/go#hdr-Compile_and_install_packages_and_dependencies) directory which essentially shadows any system installation.
+- [PATH](https://en.wikipedia.org/wiki/PATH_(variable)) needs to contain the `$GOBIN` directory for this to work.
+  ```sh
+  export PATH="$HOME/.local/bin:$HOME/go/bin:$PATH"
+  ```
+  > Executables are installed in the directory named by the GOBIN environment variable, which defaults to $GOPATH/bin or $HOME/go/bin if the GOPATH environment variable is not set. Executables in $GOROOT are installed in $GOROOT/bin or $GOTOOLDIR instead of $GOBIN.