Fast Serverless Functions for Kubernetes.

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 calledenvironments (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

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.)

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.

Running Fission on your Cluster

See the installation guide.

Compiling Fission

See the compilation guide.


Fission is in early alpha. It’s not suitable for production use just yet.

Reach us on slack or twitter.

Fission is a project by Platform9 Systems and many contributors.

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