diff --git a/scripts/freq/freqProcessor.py b/scripts/freq/freqProcessor.py
index 6304edcb200c4b8978c4c065986af900818436ce..13599ad67ecd91995babe27cb2c32edb997d2b16 100755
--- a/scripts/freq/freqProcessor.py
+++ b/scripts/freq/freqProcessor.py
@@ -5,6 +5,7 @@ import traceback
 from org.apache.nifi.processor import AbstractProcessor
 from org.apache.nifi.processor import Relationship
 from org.apache.nifi.components import PropertyDescriptor
+from org.apache.nifi.expression import ExpressionLanguageScope
 from org.apache.nifi.processor.util import StandardValidators
 from org.apache.nifi.serialization import RecordReaderFactory, RecordSetWriterFactory, SimpleRecordSchema
 from org.apache.nifi.serialization.record import RecordField, RecordFieldType
@@ -23,12 +24,12 @@ class FreqProcessor(AbstractProcessor):
     _record_reader = PropertyDescriptor.Builder().name("record-reader").displayName("Record Reader").description("Specifies the Controller Service to use for reading incoming data").identifiesControllerService(RecordReaderFactory).required(True).build()
     _record_writer = PropertyDescriptor.Builder().name("record-writer").displayName("Record Writer").description("Specifies the Controller Service to use for writing out the records").identifiesControllerService(RecordSetWriterFactory).required(True).build()
     # Record field to get the string to be analyzed from
-    _input_field = PropertyDescriptor.Builder().name("Input Field").addValidator(StandardValidators.NON_EMPTY_VALIDATOR).required(True).build()
+    _input_field = PropertyDescriptor.Builder().name("Input Field").addValidator(StandardValidators.NON_EMPTY_VALIDATOR).expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY).required(True).build()
     # Record fields to store the results (prob1, prob2) into
-    _result_field1 = PropertyDescriptor.Builder().name("Result Field 1").addValidator(StandardValidators.NON_EMPTY_VALIDATOR).required(True).build()
-    _result_field2 = PropertyDescriptor.Builder().name("Result Field 2").addValidator(StandardValidators.NON_EMPTY_VALIDATOR).required(True).build()
+    _result_field1 = PropertyDescriptor.Builder().name("Result Field 1").addValidator(StandardValidators.NON_EMPTY_VALIDATOR).expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY).required(True).build()
+    _result_field2 = PropertyDescriptor.Builder().name("Result Field 2").addValidator(StandardValidators.NON_EMPTY_VALIDATOR).expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY).required(True).build()
     # File with character frequency table (as created by freq.py)
-    _freq_file = PropertyDescriptor.Builder().name("Frequency File").addValidator(StandardValidators.FILE_EXISTS_VALIDATOR).required(True).build()
+    _freq_file = PropertyDescriptor.Builder().name("Frequency File").addValidator(StandardValidators.FILE_EXISTS_VALIDATOR).expressionLanguageSupported(ExpressionLanguageScope.VARIABLE_REGISTRY).required(True).build()
 
     def __init__(self):
         self.fc = FreqCounter()
@@ -59,14 +60,15 @@ class FreqProcessor(AbstractProcessor):
         if not self.fc_loaded:
             # Load character frequency table from given file
             # (Note: this cannot be done in initialize() since the context there doesn't contain the getProperty() method)
-            self.fc.load(str(context.getProperty("Frequency File").getValue()))
+            self.fc.load(str(context.getProperty("Frequency File").evaluateAttributeExpressions().getValue()))
             self.fc_loaded=True
             self.logger.info("Sucessfully loaded frequency file")
 
         # Get field names to work with (set in configuration)
-        self.input_field_name = context.getProperty("Input Field").getValue()[1:]
-        self.result1_field_name = context.getProperty("Result Field 1").getValue()[1:]
-        self.result2_field_name = context.getProperty("Result Field 2").getValue()[1:]
+        # (remove leading '/' if present to simulate trivial support of RecordPath)
+        self.input_field_name = context.getProperty("Input Field").evaluateAttributeExpressions().getValue().lstrip('/')
+        self.result1_field_name = context.getProperty("Result Field 1").evaluateAttributeExpressions().getValue().lstrip('/')
+        self.result2_field_name = context.getProperty("Result Field 2").evaluateAttributeExpressions().getValue().lstrip('/')
 
         try:
             flowfile = session.get()