The PKGBUILD for Hashicorp Vault (community/vault) does not build each of the database plugins. These plugins can be included later, but it is a single binary go package and the js for the web UI that is bundled in only reflects the plugins that were built at compile time and bundled into the package. I was able to fix this with the attached patch, and have included screenshots showing the current PKGBUILD's functionality (vault-without-db-plugins.png) vs full functionality (vault-with-db-plugins.png), as well as the full patched pkgbuild. Im not sure if pulling the plugin names out of the Makefile and building them in a for loop is kosher, but it worked for me!

Thanks so much for everything you do!
Andrew Tyler