capnwasm OpenAPI conversion

Paste OpenAPI JSON. The browser converts it to capnwasm's manifest IR, emits canonical .capnp, and emits canonical OpenAPI again.

Not production-ready yet. This converter demonstrates the contract pipeline. The runtime itself is still 0.0.x and needs production hardening around large data, hostile inputs, allocator lifecycle, and secure memory hygiene.

Live converter

OpenAPI ↔ Cap'n Proto bridge. For pure OpenAPI → typed JS client work, mature generators (openapi-typescript, kiota, openapi-generator) cover more edge cases. This page's niche is the rare OpenAPI ↔ .capnp pairing, and it runs the same parser/emitter modules as the CLI: parseOpenApi, buildManifest, buildCapnp, buildOpenApiJson.

Direction: OpenAPI → .capnp .capnp → OpenAPI Ready.

Same in your terminal

Input

Drop a file here, or click to upload.

Manifest summary

Run conversion.

Result

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Round-trip back to OpenAPI

Sanity check: input → manifest → canonical OpenAPI. Should match your input.

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Pros / cons

path	good for	tradeoff
OpenAPI / JSON	public REST docs, partner APIs, DevTools-friendly debugging	lowest adoption cost
Cap'n Proto	binary payloads, sparse reads, cross-language RPC, explicit schema evolution	requires schema/runtime discipline
Manifest pipeline	keeping OpenAPI, capnp, tests, probes, codecs, and tools in sync	extra contract step up front