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paasta is a free, open source build & deployment project written in Python and released under Apache-2.0. It has 1,731 GitHub stars, 251 forks and 112 open issues, and was last pushed 16 hours ago. On this registry it ranks #47 of 59 tracked projects in Build & Deployment, with 5 head-to-head comparisons available.

What is paasta?

What it is

PaaSTA is an open-source, distributed platform as a service written in Python and released under the Apache-2.0 license. It lives in the Kubernetes and Docker infrastructure ecosystem, and it was originally designed for Apache Mesos before being updated to use Kubernetes.

The project solves the problem of making service delivery safer and easier for engineering teams by taking a declarative description of a service and turning that description into deployed containers, scheduling, monitoring, logging, discovery, and cost management. Instead of requiring teams to manage Kubernetes YAML files directly, PaaSTA provides a simplified schema and configures Kubernetes along with supporting infrastructure tools.

Key capabilities

  • PaaSTA deploys and runs services as Docker containers scheduled by Kubernetes.
  • It uses SmartStack and Envoy for service registration and discovery.
  • It uses Sensu for monitoring and alerting, and Prometheus with Kubernetes Horizontal Pod Autoscaling for autoscaling services.
  • It uses Tron to run scheduled work, including nightly batches, on a timer.
  • It can optionally use Jenkins for continuous deployment workflows.
  • It collects service logs and can send them through Monk to Kafka.
  • It can use Karpenter to autoscale pools of EC2 instances for PaaSTA workloads.

Who uses it and how

  • Yelp has used PaaSTA to run production services since 2016, so it is designed for teams that need a shared platform for many services.
  • Platform or application teams write declarative service descriptions, and PaaSTA configures Kubernetes and related tools to deploy those services.
  • Services can participate in a customised SmartStack and Envoy service mesh, which allows other systems at Yelp to communicate with PaaSTA services and with each other.
  • Teams can use PaaSTA to run scheduled batch work through Tron, rather than only handling long-running services.
  • Operators can connect PaaSTA to capacity management by using Karpenter to scale EC2 instance pools that run the platform.

Getting started

The README excerpt does not mention a package manager, Docker image name, hosted option, or one-line install command. It describes PaaSTA as a Python project that requires Docker, Kubernetes, and several supporting services before it can work completely.

When to use it — and when not to

PaaSTA is appropriate for an organization that already operates Docker, Kubernetes, monitoring, service discovery, logging, and capacity systems, and that wants a declarative PaaS layer over them. It is not appropriate for a team that expects a lightweight self-hosted PaaS, because the README states that running PaaSTA outside Yelp would not be sensible without replicating many integrations and opinionated tools. The README does not list a paid product that PaaSTA replaces, so it should not be described as a direct commercial alternative.

project readme (upstream, from github) — read inline

Build Status Documentation Status

PaaSTA - Build, Deploy, Connect, and Monitor Services

PaaSTA Logo

PaaSTA is a highly-available, distributed system for building, deploying, and running services using containers and Kubernetes.

PaaSTA has been running production services at Yelp since 2016. It was originally designed to run on top of Apache Mesos but has subsequently been updated to use Kubernetes. Over time the features and functionality that PaaSTA provides have increased but the principal design remains the same.

PaaSTA aims to take a declarative description of the services that teams need to run and then ensures that those services are deployed safely, efficiently, and in a manner that is easy for the teams to maintain. Rather than managing Kubernetes YAML files, PaaSTA provides a simplified schema to describe your service and in addition to configuring Kubernetes it can also configure other infrastructure tools to provide monitoring, logging, cost management etc.

Want to know more about the opinions behind what makes PaaSTA special? Check out the PaaSTA Principles.

Components

Note: PaaSTA is an opinionated platform that uses a few un-opinionated tools. It requires a non-trivial amount of infrastructure to be in place before it works completely:

  • Docker for code delivery and containment
  • Kubernetes for code execution and scheduling (runs Docker containers)
  • Tron for running things on a timer (nightly batches)
  • SmartStack and Envoy for service registration and discovery
  • Sensu for monitoring/alerting
  • Jenkins (optionally) for continuous deployment
  • Prometheus and HPA for autoscaling services

One advantage to having a PaaS composed of components like these is you get to reuse them for other purposes. For example, at Yelp Sensu is not just for PaaSTA, it can be used to monitor all sorts of things. We also use Kubernetes to run other more complex workloads like Jolt and Cassandra. Our service mesh, which is a heavily customised version of SmartStack and Envoy, allows many systems at Yelp to communicate with PaaSTA services and each other.

On the other hand, requiring lots of components, means lots of infrastructure to setup before PaaSTA can work effectively! Realistically, running PaaSTA outside of Yelp would not be sensible, because in addition to the integrations mentioned above we also have strong opinions encoded in other tooling that you would need to replicate. Nevertheless, we code PaaSTA in the open because we think it is useful to share our approach and hope that the code can at least help others understand or solve similar problems.

Integrations and Features

In addition to the direct integrations above PaaSTA also relies on other components to provide PaaSTA users with other features and to manage compute capacity at Yelp.

  • We use Karpenter to autoscale pools of EC2 instances to run PaaSTA. Formerly we used our own autoscaler Clusterman
  • We bake AMIs using Packer
  • We collect logs from services and send them via Monk to Kafka
  • We use StatefulSets to run a few stateful PaaSTA services
  • We autotune the resources needed by each service by monitoring usage (similar to VPA)

Design Goals

  • Declarative, rather than imperative, control
  • Fault tolerance
  • Service isolation
  • Efficient use of resources
  • No single points of failure
  • Pleasant interface

Getting Started

See the getting started documentation for how to deploy PaaSTA. This reference is intended to help understand how PaaSTA works but we don't advise that you use PaaSTA in production.

Debugging PaaSTA (in VS Code)

To debug PaaSTA in VS Code, please refer to the internal PaaSTA wiki page "Debugging PaaSTA (in VS Code)".

Documentation

Read the documentation at Read the Docs.

Yelp-internal Documentation/Links

Videos / Talks About PaaSTA

License

PaaSTA is licensed under the Apache License, Version 2.0: http://www.apache.org/licenses/LICENSE-2.0

Contributing

Everyone is encouraged to contribute to PaaSTA by forking the Github repository and making a pull request or opening an issue.

Frequently asked questions

Is paasta free to use?

paasta is open source under the Apache-2.0 licence. There is no licence fee and no seat count — you can self-host it or, where the project offers one, pay a vendor for a managed version instead.

What does paasta do?

An open, distributed platform as a service

What is paasta written in?

paasta is primarily written in Python. Its source is publicly available at https://github.com/Yelp/paasta, and it has 1,731 GitHub stars.