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FME JSON GUI Specification

Welcome to the FME JSON GUI documentation!


The Transformers page describes the syntax of a .fmxj file used to define a transformer interface.

Transformer interfaces (.fmxj files) can be created and edited using the Transformer Designer.

For more details on how to create a Packaged Transformer, refer to the FME Packages SDK Guide.

The documentation for legacy .fmx files can be found here.


The syntax for defining parameters can be found here.

This syntax is used for parameters within Transformers and for User Parameters within a workspace (.fmw file). Parameters are typically defined within a Form.

For more details on working with User Parameters within Workbench, refer to the FME Workbench help page.