ZeroVM vs SmartOS: What are the differences?

ZeroVM: Open-source lightweight virtualization platform. ZeroVM is an open source virtualization technology that is based on the Chromium Native Client (NaCl) project. ZeroVM creates a secure and isolated execution environment which can run a single thread or application. ZeroVM is designed to be lightweight, portable, and can easily be embedded inside of existing storage systems; SmartOS: Converged Container and Virtual Machine Hypervisor. It combines the capabilities you get from a lightweight container OS, optimized to deliver containers, with the robust security, networking and storage capabilities you’ve come to expect and depend on from a hardware hypervisor.

ZeroVM and SmartOS can be categorized as "Virtual Machine Platforms & Containers" tools.

Some of the features offered by ZeroVM are:

• Small, Light, Fast - ZeroVM is extremely small, lightweight, and fast. An execution environment can start in as little as 5 milliseconds.
• Secure - ZeroVM security is derived from the Chromium Native Client (NaCl) project and is based on the concept of software fault isolation.
• Hyper-Scalable - ZeroVM makes it easy to create large clusters of instances, aggregating the compute power of many individual physical servers into a single execution environment.

On the other hand, SmartOS provides the following key features:

• Secure containers
• Full isolation per container in a multi-tenant environment
• Built-in networking

ZeroVM is an open source tool with 744 GitHub stars and 72 GitHub forks. Here's a link to ZeroVM's open source repository on GitHub.