Fission is a fast serverless framework for Kubernetes with a focus on developer productivity and high performance.
Fission operates on just the code: Docker and Kubernetes are abstracted away under normal operation, though you can use both to extend Fission if you want to.
Fission is extensible to any language; the core is written in Go, and language-specific parts are isolated in something called environments (more below). Fission currently supports NodeJS, Python, Ruby, Go, PHP, Bash, and any Linux executable, with more languages coming soon.
Fission maintains a pool of “warm” containers that each contain a small dynamic loader. When a function is first called, i.e. “cold-started”, a running container is chosen and the function is loaded. This pool is what makes Fission fast: cold-start latencies are typically about 100msec.
We’re built on Kubernetes because we think any non-trivial app will use a combination of serverless functions and more conventional microservices, and Kubernetes is a great framework to bring these together seamlessly.
Building on Kubernetes also means that anything you do for operations on your Kubernetes cluster — such as monitoring or log aggregation — also helps with ops on your Fission deployment.
A function is a piece of code that follows the fission function interface.
An environment contains the language- and runtime-specific parts of running a function.
The following environments are currently available:
|Binary (for executables or scripts)||
You can also extend environments or create entirely new ones if you want. (An environment is essentially just a container with a webserver and dynamic loader.)
A trigger is something that maps an event to a function; Fission supports HTTP routes as triggers today, with upcoming support for other types of event triggers, such as timers and Kubernetes events.
See the examples directory for more.