Shameless plug, but I help maintain Cortex, and "software engineering focused tools that solve (ML) issues" is a neat summary of our entire philosophy. For example, instead of notebooks, our model serving platform (https://github.com/cortexlabs/cortex) uses YAML to structure deployments, and Python scripts to write inference APIs.

It's still inextricably linked to Python, but only for writing your API. It's agnostic as to how the model itself is developed, so long as it can generate predictions.