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We are continually adding new features to the various different components of Pathling. If you are interested in specific functionality that doesn't exist yet, please get into contact with us or create an issue to help us understand your use case.

Library API: aggregate and extract operations

This change will make it possible to use the aggregate and extract operations to aggregate and transform FHIR data from Python, Java and Scala applications. This feature is currently limited to the server implementation.

See also:


The implementation of an order function will allow for the arbitrary re-ordering of resources and elements within expressions.

See FHIRPath function: order.

Improved FHIRPath support

Implementation of a number of functions is planned:

Aggregate functions

  • approxCountDistinct
  • correlation
  • countDistinct
  • covariance[Pop]
  • kurtosis
  • last
  • max
  • mean
  • min
  • percentileApprox
  • product
  • skewness
  • stdDev[Pop]
  • sumDistinct
  • variance[Pop]

Regular functions

  • contains
  • startsWith
  • endsWith

See Arbitrary function construction.

R integration

Language-specific APIs will be developed that will allow users of R to access the functionality within Pathling within their own language environment.

See R integration.


Work is planned to implement FHIR Subscriptions within Pathling. Push messaging relating to changes within the data (using criteria described using FHIRPath expressions) could be used as an engine for driving sophisticated alert systems within the clinical setting.

See Subscriptions.

Project board

You can see more planned features, in greater detail, on the Pathling project board on GitHub.