Alternatives to OpenStack

OpenFaaS makes it simple to deploy both functions and existing code to Kubernetes. With OpenFaaS developers can deploy their applications and serveless functions to their very own scalable, fault-tolerant event-driven serverless platform powered by Docker and Kubernetes.

QEMU is a generic and open source machine emulator and virtualizer.

A Platform-as-a-Service (PaaS) for cloud computing provided by Google. All applications hosted with Google App Engine is housed and managed in the same data centers that Google use for their product line. Google App Engine sandbox each individual instance and run them across multiple servers to achieve maximum uptime and fault tolerance.

With DigitalOcean App Platform you can build, deploy, and scale apps quickly using a simple, fully managed solution. Deploy code by simply pointing to a GitHub repo and let App Platform do the heavy lifting of managing the infrastructure, app runtimes and dependencies. 

Windows Sandbox is a virtual machine application that lets you quickly spin up a virtual clean OS imaged from your system's current state so that you can test programs or files in a secure environment that's isolated from your main system.