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README.md

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 # xtp-bindgen
 
-This is a typescript library for parsing an [XTP schema document](https://docs.xtp.dylibso.com/docs/host-usage/xtp-schema).
-This is experimental, more coming soon.
+XTP Bindgen is an open source framework to generate PDK bindings for [Extism](https://extism.org) plug-ins.
+It's used by the [XTP Platform](https://www.getxtp.com/), but can be used outside of the platform to define
+any Extism compatible plug-in system.
+
+## How Does It Work?
+
+[Extism](https://extism.org) has a very simple bytes-in / bytes-out interface. The host and the guest must agree
+on the interface used (exports functions, imports functions, and types). The purpose of this project is
+to create a canonical document and set of tools for defining this interface and generating bindings. That
+document is the [XTP Schema](https://docs.xtp.dylibso.com/docs/concepts/xtp-schema). This is an IDL of our creation.
+It is similar to [OpenAPI](https://www.openapis.org/), but is focused on defining plug-in interfaces, not HTTP interfaces.
+
+Once you define your interface as a schema, you can use one of the bindgens to generate code. We have some official
+bindgens available for writing PDKs, but more will be availble soon for a variety of purposes. There may also be community
+bindgens you can use.
+
+* [TypeScript](https://github.com/dylibso/xtp-typescript-bindgen)
+* [Go](https://github.com/dylibso/xtp-go-bindgen)
+* [C#](https://github.com/dylibso/xtp-csharp-bindgen)
+
+## How Do I Use A Bindgen?
+
+You can use the [XTP CLI](https://docs.xtp.dylibso.com/docs/cli/) to generate plug-ins.
+
+> *Note*: You don't need to authenticate to XTP to use the plugin generator
+
+Use the `plugin init` command to generate a plugin:
 
 ```
-npm install @dylibso/xtp-bindgen
+xtp plugin init \
+    --schema myschema.yaml \
+    --template @dylibso/xtp-typescript-bindgen \
+    --path ./myplugin \
+    --feature-flags none
 ```
 
+You can point to a bindgen template on github or directly to a bindgen bundle.
+
+
+## How Do I Write A Bindgen?
+
+
+A bindgen is simply a zip file with the following attributes:
+
+* `plugin.wasm` an extism plugin to generate the code
+* `config.yaml` a config file for the generator
+* `template` a template folder of files and templates that the generator will recursively process
+
+For reference, Here is what is inside the typescript bindgen:
+
+```
+$ tree bundle
+bundle
+├── config.yaml
+├── plugin.wasm
+└── template
+    ├── esbuild.js
+    ├── package.json.ejs
+    ├── src
+    │   ├── index.d.ts.ejs
+    │   ├── index.ts.ejs
+    │   ├── main.ts.ejs
+    │   └── pdk.ts.ejs
+    ├── tsconfig.json
+    └── xtp.toml.ejs
+```
+
+The XTP CLI will download and unpack this template, it will load the plugin, and it will recursively walk
+through the template and pass each file through the plugin to be rendered. Our official bindgens
+currently use typescript and EJS to render the projects, but these are not mandatory.
+It can be any Extism plug-in.
+