zod VS io-ts

@apexjs-org/openapi is an OpenAPI 3.1+ description library for TypeScript. You can use this package to easily create a type-safe OpenAPI (Swagger) description with Zod schema support in Node.js. In this tutorial, we use express-openapi-validator to bring the OpenAPI description to life with automatic validation and request handling.

note: In the boilerplate we used zod but you can use any other similare libraries for this part.

I'm a big fan of Zod and find it the best choice regarding the ecosystem and developer experience it provides. Although, despite its large size, it's tailored more toward the frontend world. If you're developing a backend or an application with high throughput, you should definitely give Sury a try.

In this project, we take a code-first approach when working with Firestore. Instead of relying on Firestore rules or ad-hoc validation, we define the shape and structure of a valid message directly in our application code using Zod.

The next thing to do is write our first Genkit flow to ingest data from a URL into the collection. Flows are functions that you can run via the Genkit UI or through code. Flows have strongly defined input and output schemas using zod.

Zod seems to be the go-to validation library, and is very useful in some contexts, for example if you need to do more complex or nested runtime validation. But this won't generate API docs or give you error handlers or API controllers.

Leveraging type narrowing helper libraries like Zod or ArcType can significantly both reduce the type narrowing you need to do know parsing outside data, reduce lots of boilerplate type narrowing code, and increase type safety. Many of the type lies TypeScript tells are from JSON.parse, converting Errors typed as unknown, or when reading local configuration files. This is where Zod/ArcType can really make a huge positive impact.

While Speakeasy also includes unit tests, they're organized at the root of the /tests directory with less granular separation. Its approach emphasizes documentation and type definitions, with extensive model documentation in /docs/models/. The SDK uses runtime validation through zod, which requires developers to carefully handle error objects when the API returns invalid data. This creates a different balance between compile-time and runtime type safety.

I used zod-bird to integrate Tinybird APIs (pipes and events) with Next.js. It's a wrapper around the Tinybird APIs that validates pipe results using zod schemas.

Use libraries like io-ts for runtime validation:

Qué rico. Si tenés chance meté un proceso de code review fuerte, y para el tema de I/O probá a usar https://github.com/Effect-TS/schema ó https://github.com/gcanti/io-ts que les da una solución obvia al tema de "tipos para lo que devuelva el backend", aunque es en realidad mucho más capaz que eso.

My fave is still io-ts (https://github.com/gcanti/io-ts/blob/master/docs/index.md) as I find it more flexible than zod at the ingress. The author is also working on the Effect ecosystem which also looks interesting.

I’ve been using io-ts for this and been very happy with it. [1] It’s similar to Swift’s Coding protocol in case you’re familiar.

[1] https://gcanti.github.io/io-ts/

Yeah, there are a few new concepts and it's not the easiest to pick up right away. The best introduction is here on the main documentation page.

We use https://github.com/gcanti/io-ts/blob/master/Decoder.md which has a very similar interface. It can even be used to mutate the data using https://github.com/gcanti/io-ts/blob/master/Decoder.md#the-parse-combinator.

A good way to significantly improve the reliability of your app is via improving type-safety by moving away from using any to unknown. One relevant example could be when you type your backend responses and when stringifying JSON to using unknown combined with some sort of runtime type checking. It can be done either by using built-in functionality like type guards or using an external library like io-ts, zod or yup.

Usage of TypeBox is similar with io-ts and zod, but it is much powerful and faster than them. Also, TypeBox can generate JSON schema very easily. Therefore, if you're looking for a validator library for new project and not suffering from legacy codes, I think TypeBox would be much better choice than io-ts and zod. TypeBox can totally replace them.