Introduction

This project comes from the realization that Next.js API endpoints should be easier to work with.
Why should you have to write server-side code that is totally unrelated to your frontend code, and then go through the hassle of bridging the gap between the two?

This is where Ikkan comes in. Designed to be simple, powerful and flexible, it links your server-side and client-side code together, forming a coherent set of type-safe functions that you can call from your frontend code. It is build around four main principles:

• Type-safety: All your API calls are type-safe, meaning that you will be told if you pass the wrong arguments to a function, and you will know what to expect from the return value.
• No boilerplate: Ikkan takes care of the boilerplate code for you, so you can focus on writing the logic of your API. It automatically wraps your business logic around a layer of error handling and params validation.
• Interdependence: Because you designed your API, you know how a call may affect the state of your application. If you choose to cache some results, you can easily mutate the cache from your API calls.
• No code generation: It is a pain to work with JSON files, or to manually run a command to generate your API. Ikkan is designed to be used with your existing codebase, in TypeScript, like the rest of your project.

Note that this library is designed so that everything is optional. If you know what you are doing, you can still call your API in the traditional way, without using Ikkan, or define your endpoints in a different way. But if you want to use Ikkan, it will be there for you.

---

Current limitations

Ikkan is still in its early stages, and as such, it has some limitations:

• Limited types support: Your endpoints using Ikkan must return a value that can be serialized to JSON. There is no support for Blob, FormData, ReadableStream, etc.
• No undefined return: The undefined type is not supported by Ikkan. If you want to return undefined, you should return null instead.
• No support for the HEAD method: Ikkan does not support the HEAD method (but who uses it anyway?).
• Imperative server-side imports: You must not declatively import server-side only imports, as they will crash client-side code. Instead, you should use the ssi property of the IkkanConfig object to import them once, when the endpoint is first compiled.