Fission: Serverless Functions for Kubernetes @fissionio

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.

Performance: 100msec cold start

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.

Kubernetes is the right place for Serverless

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.

Fission Concepts

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:

Environment Image
Binary (for executables or scripts) fission/binary-env
Go fission/go-env
.NET fission/dotnet-env
.NET 2.0 fission/dotnet20-env
NodeJS (Alpine) fission/node-env
NodeJS (Debian) fission/node-env-debian
Perl fission/perl-env
PHP 7 fission/php-env
Python 3 fission/python-env
Ruby fission/ruby-env

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.


  # Add the stock NodeJS env to your Fission deployment
  $ fission env create --name nodejs --image fission/node-env

  # A javascript one-liner that prints "hello world"
  $ curl > hello.js

  # Upload your function code to fission
  $ fission function create --name hello --env nodejs --code hello.js

  # Map GET /hello to your new function
  $ fission route create --method GET --url /hello --function hello

  # Run the function.  This takes about 100msec the first time.
  $ fission function test --name hello
  Hello, world!

See the examples directory for more.