RudderStack›RudderStack› offers Transformations

Transformations lets engineering teams modify event data in flight between collection and delivery using JavaScript or Python, with quickstart templates, reusable transformation libraries, version control through GitHub, and a programmatic API. Typical uses include cleaning and reformatting payloads, filtering events with allowlists and denylists, enriching events with external API calls, and masking sensitive fields on a per-destination basis.

The product is also the enforcement mechanism for data quality and compliance rules defined elsewhere in the platform, applying them as events pass through the pipeline. It supports advanced cases such as real-time activations, real-time personalization backed by Redis, and dynamic header injection for webhook destinations, and is packaged without a transformation limit on higher plan tiers.