I'm not sure how it works with Lambda as far as using compiled code, so I'm not super confident about this, but... at first blush the obvious thing to do would

I'm not sure how it works with Lambda as far as using compiled code, so I'm not super confident about this, but... at first blush the obvious thing to do would seem to be "call the Fortran code from Python directly" (as @ReleaseCandidat also says). There are mechanisms to do that... my only question is where or not Lambdas support that. If not, you might have to deploy a network callable service on an EC2 instance or whatever, and call into it from your Lambda or something. Edit: Reading this[1] it sounds like it is possible in principle to deploy Python bundles on Lambda that call compiled libs. It might take some experimenting to work out the details, but I think you could probably make this approach work. [1]: https://aws.amazon.com/premiumsupport/knowledge-center/lambda-python-package-compatible/ https://aws.amazon.com/premiumsupport/knowledge-center/lambd...