JSON to Haskell

Convert JSON to Haskell data type.

This tool is designed to provide a seamless experience for developers by handling complex operations directly in your browser with maximum speed and security.

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Customizable

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Dev-Friendly

Easy Export

This tool transforms JSON into clean, idiomatic Haskell code, generating algebraic data types (ADTs) and Aeson instances for seamless serialization and deserialization. It handles various Haskell data mapping strategies, including support for nested records and optional fields, making it easy to work with JSON in a high-level, functional way. The tool generates `FromJSON` and `ToJSON` instances, which are required for high-performance JSON handling in Haskell applications. It is an ideal tool for developers working on cloud infrastructure, backend services, or complex data processing pipelines where Haskell's strong type system and functional purity are key assets.

Paste your JSON to generate Haskell data types with `Aeson` instances. It handles nested objects by creating multiple data types.

Haskell is a strongly typed language where JSON mapping is explicit and requires a specific structure. This tool handles the tedious work of mapping types and creating data structures, providing you with a clean, typed foundation that integrates perfectly with the Aeson library, saving you significant development time and ensuring your Haskell models are always perfectly aligned with your JSON data.

Example Input

{
  "id": 1,
  "name": "John Doe",
  "email": "john@example.com",
  "isActive": true,
  "tags": ["admin", "dev"],
  "profile": {
    "bio": "Software Engineer",
    "skills": ["Go", "React", "TypeScript"]
  }
}

Example Output

data User = User
    { id :: Int
    , name :: String
    , email :: String
    , isActive :: Bool
    } deriving (Show, Generic)
instance FromJSON User

GHC Extensions

Fix: The generated code may require GHC extensions like `DeriveGeneric`. Ensure these are enabled in your Haskell file.

Does it support Aeson?

Yes, it generates instances compatible with the popular `Aeson` library.

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