JSON to Rust Structs with serde
Rust's type system is strict, which makes JSON deserialization a bit more involved than in dynamic languages. You need structs, you need serde derives, and you need the field types to match exactly. Getting any of this wrong gives you a compilation error or a runtime panic. This tool generates the boilerplate so you can skip straight to the interesting part.
The generated structs come with #[derive(Serialize, Deserialize)] and#[serde(rename_all = "camelCase")] already applied. Field names follow Rust's snake_case convention, with #[serde(rename = "originalKey")] attributes where the JSON key doesn't match. Nullable fields use Option<T>.
Serde Configuration
serde is incredibly flexible but also has a steep learning curve. The generated code uses sensible defaults — Clone, Debug, PartialEq in the derive macro for easy debugging and testing. If you need custom serialization logic (like parsing dates or enums from strings), you can add #[serde(with = "...")] attributes on top of the generated base.
reqwest and API Integration
If you're using reqwest for HTTP requests, you can deserialize directly into your generated structs with response.json::<RootObject>().await?. No intermediate steps, no manual parsing. The same structs work for serializing request bodies too.
Handling Missing Fields
Rust doesn't have null — it has Option<T>. By default, serde expects every declared field to be present in the JSON. For fields that might be absent, you'll need#[serde(default)] or Option<T>. The generated structs useOption for fields that were null in the sample data, but you should review and add it to any field that your API might omit.
Performance Considerations
serde_json is one of the fastest JSON parsers in any language. By deserializing into typed structs instead of serde_json::Value, you get zero-copy string parsing and avoid the overhead of a dynamic hashmap. For high-throughput services, this makes a real difference. The generated structs are the optimal approach for production Rust code.
Related JSON Tools
For Go services in the same microservice architecture, use our JSON to Go converter. Generate Protobuf definitions for inter-service communication. Format complex API responses before converting.