1. Migrate to Speakeasy

Whilst both Stainless and Speakeasy ended up with a very different configuration paradigm, they can generate very similar code once the configuration is migrated from Stainless-form (stainless.yml) to Speakeasy-form (OpenAPI Overlays). This process is not entirely deterministic, but a good few prompts into a coding agent can do the vast bulk of the work.

We've already been working with a few companies to:

    1. Do a seamless migration where we apply a few custom code patches to tighten the delta between the generated code to the point that this becomes as close to a backwards compatible a change as feasible.
    2. Re-build workflow configuration from the Stainless paradigm (cloud based) to the Speakeasy paradigm (CLI/GitHub Action based) so this is extremely hands-off.

Source: I work at Speakeasy.

2. There are a lot of OSS SDK generators -- this one is probably the biggest aggregator https://openapi.tools/categories/sdk-generators