Contributing upstream Edit on github

We encourage participation in open source projects and strive to have as few rules for this as possible, we expect Zalandos to follow common sense on what code and information they contribute - if in doubt, contact the open source team, or talk to your lead.


  • We encourage contributions upstream
  • Make sure you don’t share confidential information
  • Don’t contribute code which gives us an edge over competitors
  • Only sign allowlisted CLAs - ask the open source team or legal for guidance
  • Find projects to contribute to on the Zalando Tech Radar

Common contribution rules

  • Do not share customer data or confidential Zalando information
  • Code that cannot be contributed upstream
    • confidential source code
    • recommendation algorithms
    • search functionalities that give us an edge over competitors
  • Remember that Zalando legally have ownership over your contributions as you are an employee of Zalando SE

Non-code contributions

Contributions such as reporting issues, writing documentation, reviewing code and participating in project maintenance such as creating roadmaps, grooming backlogs etc.

These activities are all sanctioned and encouraged as part of your employment at Zalando.

Code contributions

Upstream code contributions are also encouraged and is a natural extension of our dependency of open source projects in our tech stack. Code contributions can generally be divided into 2 categories:

  • Contributions triggered by a work task: eg. a dependency have a bug or shortcoming which block your work
  • Contributions on your own initiative

Both are sanctioned and does not require a review. Simply ensure that the project you are contributing to is not licensed under AGPL.

Finding projects to contribute to

We recommend taking a look at the Zalando Tech Radar to get an overview of the projects we actively use, which would be an obvious starting point for contributions.

Allowlisted CLAs

If a non-Zalando open source project asks you to sign a contributor agreement, get it cleared with the open source team, unless it is one of the following which have been allowlisted:

  • Apache CLA
  • Project Harmony Contributor Agreements
  • Mozilla Comitters Agreement
  • Adobe Open Source Contributor Agreement
  • Google iCLA
  • Developer Certificate Of Origin
  • Pivotal CLA
  • Lightbend CLA
  • OpenID CLA

This page is Licensed under the MIT license