--- layout: "docs" page_title: "Plugin Basics" sidebar_current: "docs-plugins-basics" description: |- This page documents the basics of how the plugin system in Terraform works, and how to setup a basic development environment for plugin development if you're writing a Terraform plugin. --- # Plugin Basics This page documents the basics of how the plugin system in Terraform works, and how to setup a basic development environment for plugin development if you're writing a Terraform plugin. ~> **Advanced topic!** Plugin development is a highly advanced topic in Terraform, and is not required knowledge for day-to-day usage. If you don't plan on writing any plugins, we recommend not reading this section of the documentation. ## How it Works Terraform providers and provisioners are provided via plugins. Each plugin exposes an implementation for a specific service, such as AWS, or provisioner, such as bash. Plugins are executed as a separate process and communicate with the main Terraform binary over an RPC interface. More details are available in [Internal Docs](/docs/internals/internal-plugins.html). The code within the binaries must adhere to certain interfaces. The network communication and RPC is handled automatically by higher-level Terraform libraries. The exact interface to implement is documented in its respective documentation section. ## Installing a Plugin To install a plugin, put the binary somewhere on your filesystem, then configure Terraform to be able to find it. The configuration where plugins are defined is `~/.terraformrc` for Unix-like systems and `%APPDATA%/terraform.rc` for Windows. An example that configures a new provider is shown below: ```hcl providers { privatecloud = "/path/to/privatecloud" } ``` The key `privatecloud` is the _prefix_ of the resources for that provider. For example, if there is `privatecloud_instance` resource, then the above configuration would work. The value is the name of the executable. This can be a full path. If it isn't a full path, the executable will be looked up on the `PATH`. ## Developing a Plugin Developing a plugin is simple. The only knowledge necessary to write a plugin is basic command-line skills and basic knowledge of the [Go programming language](http://golang.org). -> **Note:** A common pitfall is not properly setting up a $GOPATH. This can lead to strange errors. You can read more about this [here](https://golang.org/doc/code.html) to familiarize yourself. Create a new Go project somewhere in your `$GOPATH`. If you're a GitHub user, we recommend creating the project in the directory `$GOPATH/src/github.com/USERNAME/terraform-NAME`, where `USERNAME` is your GitHub username and `NAME` is the name of the plugin you're developing. This structure is what Go expects and simplifies things down the road. With the directory made, create a `main.go` file. This project will be a binary so the package is "main": ```golang package main import ( "github.com/hashicorp/terraform/plugin" ) func main() { plugin.Serve(new(MyPlugin)) } ``` And that's basically it! You'll have to change the argument given to `plugin.Serve` to be your actual plugin, but that is the only change you'll have to make. The argument should be a structure implementing one of the plugin interfaces (depending on what sort of plugin you're creating). Terraform plugins must follow a very specific naming convention of `terraform-TYPE-NAME`. For example, `terraform-provider-aws`, which tells Terraform that the plugin is a provider that can be referenced as "aws".