Motivation

pinot-segment-local/src/main/java/org/apache/pinot/segment/local/recordtransformer/ExpressionTransformer.java and pinot-segment-local/src/main/java/org/apache/pinot/segment/local/recordtransformer/enricher/function/CustomFunctionEnricher.java still carry reciprocal TODOs to merge the two implementations.

Both code paths evaluate function-based transformations during ingestion, but they live behind different extension points (RecordTransformer vs RecordEnricher). That makes behavior drift and duplicate maintenance more likely.

Scope

• Document the overlap and intended ownership between the two implementations.
• Consolidate shared evaluation logic behind one path or a shared abstraction.
• Preserve current ingestion behavior for transform configs and enricher configs.
• Add or update focused tests for parity and backward compatibility.

Notes

Observed on upstream/master on April 15, 2026.