The popularity of AWS Lambda, the serverless compute platform, has resulted in many frameworks that allow similar functionality, both as cloud provider-managed (for example, Azure Functions, Google Cloud Functions, and IBM Cloud Functions) and self-managed frameworks. Kubeless is one of the self-managed ones. As in any new fast-moving technology, there is no clear winner yet. Here are some open source alternatives to Kubeless that are Kubernetes friendly:

• Serverless (https://serverless.com/): A Node.js-based serverless application framework that can deploy and manage functions on multiple cloud providers, including Azure. Kubernetes support is provided via Kubeless.
• OpenFaas (https://www.openfaas.com/): A portable framework, providing ease of use for building serverless functions with Docker and Kubernetes, which has first-class support for metrics.

• Fission.io (https://fission.io/): A fast, open source serverless framework for Kubernetes with a focus on developer productivity and high performance.
• Apache OpenWhisk (https://openwhisk.apache.org/): An open source, distributed serverless platform that executes functions (fx) in response to events at any scale.
• Knative (https://cloud.google.com/knative/): This enables developers to focus on writing interesting code, without worrying about the difficult parts of building, deploying, and managing an application.

Kubeless was chosen based on its compatibility with the highest GitHub star winner (28K+ at the time of writing) serverless framework (https://github.com/serverless/serverless).