diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/api/RuleEngineContext.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/api/RuleEngineContext.kt
index e28895cd..eb2e973b 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/api/RuleEngineContext.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/api/RuleEngineContext.kt
@@ -1,8 +1,6 @@
 package org.hisp.dhis.rules.api
 
 import org.hisp.dhis.rules.models.Rule
-import org.hisp.dhis.rules.models.RuleEnrollment
-import org.hisp.dhis.rules.models.RuleEvent
 import org.hisp.dhis.rules.models.RuleVariable
 
 data class RuleEngineContext(
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleConditionEvaluator.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleConditionEvaluator.kt
index 4b6eaf4f..50577304 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleConditionEvaluator.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleConditionEvaluator.kt
@@ -4,11 +4,10 @@ import org.hisp.dhis.lib.expression.Expression
 import org.hisp.dhis.lib.expression.spi.ExpressionData
 import org.hisp.dhis.lib.expression.spi.IllegalExpressionException
 import org.hisp.dhis.rules.createLogger
-import org.hisp.dhis.rules.models.Rule
-import org.hisp.dhis.rules.models.*
 import org.hisp.dhis.rules.engine.RuleEvaluationResult.Companion.errorRule
 import org.hisp.dhis.rules.engine.RuleEvaluationResult.Companion.evaluatedResult
 import org.hisp.dhis.rules.engine.RuleEvaluationResult.Companion.notEvaluatedResult
+import org.hisp.dhis.rules.models.*
 import org.hisp.dhis.rules.utils.unwrapVariableName
 
 internal class RuleConditionEvaluator {
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleEngineMultipleExecution.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleEngineMultipleExecution.kt
index efcfbf03..11b83508 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleEngineMultipleExecution.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleEngineMultipleExecution.kt
@@ -1,6 +1,5 @@
 package org.hisp.dhis.rules.engine
 
-import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.models.*
 
 internal class RuleEngineMultipleExecution {
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleVariableValueMapBuilder.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleVariableValueMapBuilder.kt
index 636d75da..3e9dddd5 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleVariableValueMapBuilder.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/engine/RuleVariableValueMapBuilder.kt
@@ -6,8 +6,6 @@ import kotlinx.datetime.toLocalDateTime
 import org.hisp.dhis.rules.models.*
 import org.hisp.dhis.rules.utils.RuleEngineUtils
 import org.hisp.dhis.rules.utils.currentDate
-import kotlin.collections.ArrayList
-import kotlin.collections.HashMap
 
 internal class RuleVariableValueMapBuilder private constructor() {
     val allConstantValues: MutableMap<String, String> = HashMap()
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/Option.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/Option.kt
index 51eae686..43b597a3 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/Option.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/Option.kt
@@ -1,6 +1,8 @@
 package org.hisp.dhis.rules.models
 
-/**
- * @author rajazubair
- */
+import kotlin.js.ExperimentalJsExport
+import kotlin.js.JsExport
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
 data class Option(val name: String, val code: String)
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleAttributeValue.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleAttributeValue.kt
index 404b3542..353b14e1 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleAttributeValue.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleAttributeValue.kt
@@ -1,5 +1,10 @@
 package org.hisp.dhis.rules.models
 
+import kotlin.js.ExperimentalJsExport
+import kotlin.js.JsExport
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
 data class RuleAttributeValue(
     val trackedEntityAttribute: String,
     val value: String
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleValidationResult.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleValidationResult.kt
index 33afd4c4..0cd218ae 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleValidationResult.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleValidationResult.kt
@@ -1,5 +1,7 @@
 package org.hisp.dhis.rules.models
 
+import kotlin.js.ExperimentalJsExport
+import kotlin.js.JsExport
 import kotlin.jvm.JvmOverloads
 
 /*
@@ -30,6 +32,8 @@ import kotlin.jvm.JvmOverloads
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+@JsExport
+@OptIn(ExperimentalJsExport::class)
 data class RuleValidationResult @JvmOverloads constructor(
         val valid: Boolean,
         val errorMessage: String? = null,
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariable.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariable.kt
index 9013a37c..aafd86a0 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariable.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariable.kt
@@ -1,10 +1,13 @@
 package org.hisp.dhis.rules.models
 
 import org.hisp.dhis.rules.engine.RuleVariableValue
-import org.hisp.dhis.rules.engine.RuleVariableValueMapBuilder
 
 interface RuleVariable {
+    val name: String
+    val useCodeForOptionSet: Boolean
     val options: List<Option>
+    val field: String
+    val fieldType: RuleValueType
     fun createValues(
         ruleEvent: RuleEvent?,
         allEventValues: Map<String, List<RuleDataValue>>,
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableAttribute.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableAttribute.kt
index 4a8bd655..f24443d7 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableAttribute.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableAttribute.kt
@@ -2,15 +2,14 @@ package org.hisp.dhis.rules.models
 
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.engine.RuleVariableValue
-import org.hisp.dhis.rules.engine.RuleVariableValueMapBuilder
 import org.hisp.dhis.rules.utils.currentDate
 
 data class RuleVariableAttribute(
-    val name: String,
-    val useCodeForOptionSet: Boolean,
+    override val name: String,
+    override val useCodeForOptionSet: Boolean,
     override val options: List<Option>,
-    val trackedEntityAttribute: String,
-    val trackedEntityAttributeType: RuleValueType
+    override val field: String,
+    override val fieldType: RuleValueType
 ) : RuleVariable {
     override fun createValues(
         ruleEvent: RuleEvent?,
@@ -20,15 +19,15 @@ data class RuleVariableAttribute(
     ): Map<String, RuleVariableValue> {
         val valueMap: MutableMap<String, RuleVariableValue> = HashMap()
         val currentDate = LocalDate.Companion.currentDate()
-        val variableValue = if (currentEnrollmentValues.containsKey(trackedEntityAttribute)) {
-            val value = currentEnrollmentValues[trackedEntityAttribute]
+        val variableValue = if (currentEnrollmentValues.containsKey(field)) {
+            val value = currentEnrollmentValues[field]
             val optionValue = if (useCodeForOptionSet) value!!.value else getOptionName(value!!.value)!!
             RuleVariableValue(
-                trackedEntityAttributeType, optionValue,
+                fieldType, optionValue,
                 listOf(optionValue), currentDate.toString()
             )
         } else {
-            RuleVariableValue(trackedEntityAttributeType)
+            RuleVariableValue(fieldType)
         }
         valueMap[name] = variableValue
         return valueMap
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableCalculatedValue.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableCalculatedValue.kt
index 4b07d7a5..f551e690 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableCalculatedValue.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableCalculatedValue.kt
@@ -1,7 +1,6 @@
 package org.hisp.dhis.rules.models
 
 import org.hisp.dhis.rules.engine.RuleVariableValue
-import org.hisp.dhis.rules.engine.RuleVariableValueMapBuilder
 
 /*
 * Copyright (c) 2004-2018, University of Oslo
@@ -33,11 +32,11 @@ import org.hisp.dhis.rules.engine.RuleVariableValueMapBuilder
  * @author Zubair Asghar.
  */
 class RuleVariableCalculatedValue(
-    val name: String,
-    val useCodeForOptionSet: Boolean,
+    override val name: String,
+    override val useCodeForOptionSet: Boolean,
     override val options: List<Option>,
-    val calculatedValueVariable: String,
-    val calculatedValueType: RuleValueType
+    override val field: String,
+    override val fieldType: RuleValueType
 ) : RuleVariable {
     override fun createValues(
         ruleEvent: RuleEvent?,
@@ -46,7 +45,7 @@ class RuleVariableCalculatedValue(
         currentEventValues: Map<String, RuleDataValue>
     ): Map<String, RuleVariableValue> {
         val valueMap: MutableMap<String, RuleVariableValue> = HashMap()
-        valueMap[name] = RuleVariableValue(calculatedValueType)
+        valueMap[name] = RuleVariableValue(fieldType)
         return valueMap
     }
 }
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableCurrentEvent.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableCurrentEvent.kt
index aaef015a..2f380331 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableCurrentEvent.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableCurrentEvent.kt
@@ -1,16 +1,15 @@
 package org.hisp.dhis.rules.models
 
 import org.hisp.dhis.rules.engine.RuleVariableValue
-import org.hisp.dhis.rules.engine.RuleVariableValueMapBuilder
 import org.hisp.dhis.rules.utils.getLastUpdateDate
 
 class RuleVariableCurrentEvent(
-    val name: String,
-    val useCodeForOptionSet: Boolean,
+    override val name: String,
+    override val useCodeForOptionSet: Boolean,
     override val options: List<Option>,
-    override val dataElement: String,
-    override val dataElementType: RuleValueType,
-) : RuleVariableDataElement {
+    override val field: String,
+    override val fieldType: RuleValueType,
+) : RuleVariable {
     override fun createValues(
         ruleEvent: RuleEvent?,
         allEventValues: Map<String, List<RuleDataValue>>,
@@ -19,15 +18,15 @@ class RuleVariableCurrentEvent(
     ): Map<String, RuleVariableValue> {
         val valueMap: MutableMap<String, RuleVariableValue> = HashMap()
         val variableValue: RuleVariableValue
-        variableValue = if (currentEventValues.containsKey(dataElement)) {
-            val value = currentEventValues[dataElement]
+        variableValue = if (currentEventValues.containsKey(field)) {
+            val value = currentEventValues[field]
             val optionValue = if (useCodeForOptionSet) value!!.value else getOptionName(value!!.value)!!
             RuleVariableValue(
-                dataElementType, optionValue,
+                fieldType, optionValue,
                 listOf(optionValue), getLastUpdateDate(listOf(value))
             )
         } else {
-            RuleVariableValue(dataElementType)
+            RuleVariableValue(fieldType)
         }
         valueMap[name] = variableValue
         return valueMap
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableDataElement.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableDataElement.kt
deleted file mode 100644
index 17767a63..00000000
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableDataElement.kt
+++ /dev/null
@@ -1,7 +0,0 @@
-package org.hisp.dhis.rules.models
-
-
-internal interface RuleVariableDataElement : RuleVariable {
-    val dataElement: String
-    val dataElementType: RuleValueType
-}
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestEvent.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestEvent.kt
index 9e20708b..ed8177c8 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestEvent.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestEvent.kt
@@ -1,17 +1,16 @@
 package org.hisp.dhis.rules.models
 
 import org.hisp.dhis.rules.engine.RuleVariableValue
-import org.hisp.dhis.rules.engine.RuleVariableValueMapBuilder
 import org.hisp.dhis.rules.utils.getLastUpdateDate
 import org.hisp.dhis.rules.utils.values
 
 class RuleVariableNewestEvent(
-    val name: String,
-    val useCodeForOptionSet: Boolean,
+    override val name: String,
+    override val useCodeForOptionSet: Boolean,
     override val options: List<Option>,
-    override val dataElement: String,
-    override val dataElementType: RuleValueType,
-) : RuleVariableDataElement {
+    override val field: String,
+    override val fieldType: RuleValueType,
+) : RuleVariable {
     override fun createValues(
         ruleEvent: RuleEvent?,
         allEventValues: Map<String, List<RuleDataValue>>,
@@ -19,15 +18,15 @@ class RuleVariableNewestEvent(
         currentEventValues: Map<String, RuleDataValue>
     ): Map<String, RuleVariableValue> {
         val valueMap: MutableMap<String, RuleVariableValue> = HashMap()
-        val ruleDataValues = allEventValues[dataElement]
+        val ruleDataValues = allEventValues[field]
         if (ruleDataValues.isNullOrEmpty()) {
-            valueMap[name] = RuleVariableValue(dataElementType)
+            valueMap[name] = RuleVariableValue(fieldType)
         } else {
             val variableValue: RuleVariableValue
             val value = ruleDataValues[0]
             val optionValue = if (useCodeForOptionSet) value.value else getOptionName(value.value)!!
             variableValue = RuleVariableValue(
-                dataElementType, optionValue,
+                fieldType, optionValue,
                 values(ruleDataValues), getLastUpdateDate(ruleDataValues)
             )
             valueMap[name] = variableValue
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestStageEvent.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestStageEvent.kt
index 13112b89..6961f98c 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestStageEvent.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestStageEvent.kt
@@ -1,18 +1,17 @@
 package org.hisp.dhis.rules.models
 
 import org.hisp.dhis.rules.engine.RuleVariableValue
-import org.hisp.dhis.rules.engine.RuleVariableValueMapBuilder
 import org.hisp.dhis.rules.utils.getLastUpdateDate
 import org.hisp.dhis.rules.utils.values
 
 class RuleVariableNewestStageEvent(
-    val name: String,
-    val useCodeForOptionSet: Boolean,
+    override val name: String,
+    override val useCodeForOptionSet: Boolean,
     override val options: List<Option>,
-    override val dataElement: String,
-    override val dataElementType: RuleValueType,
+    override val field: String,
+    override val fieldType: RuleValueType,
     val programStage: String
-) : RuleVariableDataElement {
+) : RuleVariable {
 
     override fun createValues(
         ruleEvent: RuleEvent?,
@@ -22,7 +21,7 @@ class RuleVariableNewestStageEvent(
     ): Map<String, RuleVariableValue> {
         val valueMap: MutableMap<String, RuleVariableValue> = HashMap()
         val stageRuleDataValues: MutableList<RuleDataValue> = ArrayList()
-        val sourceRuleDataValues = allEventValues[dataElement]
+        val sourceRuleDataValues = allEventValues[field]
         if (!sourceRuleDataValues.isNullOrEmpty()) {
 
             // filter data values based on program stage
@@ -33,13 +32,13 @@ class RuleVariableNewestStageEvent(
             }
         }
         if (stageRuleDataValues.isEmpty()) {
-            valueMap[name] = RuleVariableValue(dataElementType)
+            valueMap[name] = RuleVariableValue(fieldType)
         } else {
             val variableValue: RuleVariableValue
             val value = stageRuleDataValues[0]
             val optionValue = if (useCodeForOptionSet) value.value else getOptionName(value.value)!!
             variableValue = RuleVariableValue(
-                dataElementType, optionValue,
+                fieldType, optionValue,
                 values(stageRuleDataValues),
                 getLastUpdateDate(stageRuleDataValues)
             )
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariablePreviousEvent.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariablePreviousEvent.kt
index 827672e4..7ca94c8b 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariablePreviousEvent.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/models/RuleVariablePreviousEvent.kt
@@ -1,17 +1,16 @@
 package org.hisp.dhis.rules.models
 
 import org.hisp.dhis.rules.engine.RuleVariableValue
-import org.hisp.dhis.rules.engine.RuleVariableValueMapBuilder
 import org.hisp.dhis.rules.utils.getLastUpdateDateForPrevious
 import org.hisp.dhis.rules.utils.values
 
 class RuleVariablePreviousEvent(
-    val name: String,
-    val useCodeForOptionSet: Boolean,
+    override val name: String,
+    override val useCodeForOptionSet: Boolean,
     override val options: List<Option>,
-    override val dataElement: String,
-    override val dataElementType: RuleValueType
-) : RuleVariableDataElement {
+    override val field: String,
+    override val fieldType: RuleValueType
+) : RuleVariable {
     override fun createValues(
         ruleEvent: RuleEvent?,
         allEventValues: Map<String, List<RuleDataValue>>,
@@ -20,7 +19,7 @@ class RuleVariablePreviousEvent(
     ): Map<String, RuleVariableValue> {
         val valueMap: MutableMap<String, RuleVariableValue> = HashMap()
         var variableValue: RuleVariableValue? = null
-        val ruleDataValues = allEventValues[dataElement]
+        val ruleDataValues = allEventValues[field]
         if (ruleEvent != null && !ruleDataValues.isNullOrEmpty()) {
             for (ruleDataValue in ruleDataValues) {
                 // We found preceding value to the current currentEventValues,
@@ -29,7 +28,7 @@ class RuleVariablePreviousEvent(
                     val optionValue =
                         if (useCodeForOptionSet) ruleDataValue.value else getOptionName(ruleDataValue.value)!!
                     variableValue = RuleVariableValue(
-                        dataElementType, optionValue,
+                        fieldType, optionValue,
                         values(ruleDataValues),
                         getLastUpdateDateForPrevious(ruleDataValues, ruleEvent)
                     )
@@ -38,7 +37,7 @@ class RuleVariablePreviousEvent(
             }
         }
         if (variableValue == null) {
-            variableValue = RuleVariableValue(dataElementType)
+            variableValue = RuleVariableValue(fieldType)
         }
         valueMap[name] = variableValue
         return valueMap
diff --git a/src/commonMain/kotlin/org/hisp/dhis/rules/utils/RuleEngineUtils.kt b/src/commonMain/kotlin/org/hisp/dhis/rules/utils/RuleEngineUtils.kt
index 084b6409..6acf9ac3 100644
--- a/src/commonMain/kotlin/org/hisp/dhis/rules/utils/RuleEngineUtils.kt
+++ b/src/commonMain/kotlin/org/hisp/dhis/rules/utils/RuleEngineUtils.kt
@@ -1,7 +1,5 @@
 package org.hisp.dhis.rules.utils
 
-import org.hisp.dhis.rules.api.ItemValueType
-
 /*
 * Copyright (c) 2004-2020, University of Oslo
 * All rights reserved.
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/ConstantsValueTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/ConstantsValueTest.kt
index abffcedb..b034a7cd 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/ConstantsValueTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/ConstantsValueTest.kt
@@ -3,9 +3,7 @@ package org.hisp.dhis.rules
 import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.api.RuleEngine
-import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.api.RuleEngineContext
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
 import org.hisp.dhis.rules.models.*
 import org.hisp.dhis.rules.utils.currentDate
 import kotlin.test.Test
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/ProgramRuleVariableTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/ProgramRuleVariableTest.kt
index f7b75d61..b08a641b 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/ProgramRuleVariableTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/ProgramRuleVariableTest.kt
@@ -3,9 +3,7 @@ package org.hisp.dhis.rules
 import kotlinx.datetime.Instant
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.api.RuleEngine
-import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.api.RuleEngineContext
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
 import org.hisp.dhis.rules.models.*
 import org.hisp.dhis.rules.utils.currentDate
 import kotlin.test.Test
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineEffectTypesTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineEffectTypesTest.kt
index 35c14f05..ade1de99 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineEffectTypesTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineEffectTypesTest.kt
@@ -4,14 +4,14 @@ import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.RuleEngineTestUtils.getRuleEngineContext
 import org.hisp.dhis.rules.api.RuleEngine
-import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.api.RuleEngineContext
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
-import org.hisp.dhis.rules.models.*
+import org.hisp.dhis.rules.models.Rule
+import org.hisp.dhis.rules.models.RuleAction
+import org.hisp.dhis.rules.models.RuleDataValue
+import org.hisp.dhis.rules.models.RuleEvent
 import org.hisp.dhis.rules.utils.currentDate
 import kotlin.test.Test
 import kotlin.test.assertEquals
-import kotlin.test.assertTrue
 
 // ToDo: function tests (check that function invocations are producing expected values; check nested function invocation)
 // ToDo: various source type tests (referencing variables from different events)
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineFunctionTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineFunctionTest.kt
index 949a044c..dffd933f 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineFunctionTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineFunctionTest.kt
@@ -2,13 +2,9 @@ package org.hisp.dhis.rules
 
 import kotlinx.datetime.*
 import org.hisp.dhis.rules.api.RuleEngine
-import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.api.RuleEngineContext
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
 import org.hisp.dhis.rules.models.*
 import org.hisp.dhis.rules.utils.currentDate
-import kotlin.collections.ArrayList
-import kotlin.collections.HashMap
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineGetDescriptionTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineGetDescriptionTest.kt
index c010322a..2150cbd0 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineGetDescriptionTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineGetDescriptionTest.kt
@@ -4,9 +4,9 @@ import org.hisp.dhis.rules.api.DataItem
 import org.hisp.dhis.rules.api.ItemValueType
 import org.hisp.dhis.rules.api.RuleEngine
 import org.hisp.dhis.rules.engine.DefaultRuleEngine
-import org.hisp.dhis.rules.models.RuleEngineValidationException
 import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.models.RuleAction
+import org.hisp.dhis.rules.models.RuleEngineValidationException
 import kotlin.test.*
 
 /*
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineTest.kt
index 10402ca4..f7681f74 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineTest.kt
@@ -4,7 +4,6 @@ import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.api.RuleEngine
 import org.hisp.dhis.rules.api.RuleEngineContext
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
 import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.models.RuleEvent
 import org.hisp.dhis.rules.utils.currentDate
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineTestUtils.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineTestUtils.kt
index e935b43d..2b693b45 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineTestUtils.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineTestUtils.kt
@@ -2,8 +2,6 @@ package org.hisp.dhis.rules
 
 import org.hisp.dhis.rules.api.RuleEngineContext
 import org.hisp.dhis.rules.models.Rule
-import org.hisp.dhis.rules.models.RuleEnrollment
-import org.hisp.dhis.rules.models.RuleEvent
 import org.hisp.dhis.rules.models.RuleVariable
 
 /*
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineValueTypesTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineValueTypesTest.kt
index 25bae9b2..373f2e64 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineValueTypesTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineValueTypesTest.kt
@@ -3,9 +3,7 @@ package org.hisp.dhis.rules
 import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.api.RuleEngine
-import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.api.RuleEngineContext
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
 import org.hisp.dhis.rules.models.*
 import org.hisp.dhis.rules.utils.currentDate
 import kotlin.test.Test
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineVariableNameTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineVariableNameTest.kt
index c91acdd2..51dd115d 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineVariableNameTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/RuleEngineVariableNameTest.kt
@@ -4,8 +4,6 @@ import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.RuleEngineTestUtils.getRuleEngineContext
 import org.hisp.dhis.rules.api.RuleEngine
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
-import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.models.*
 import org.hisp.dhis.rules.utils.currentDate
 import kotlin.test.Test
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/VariableValueTypeTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/VariableValueTypeTest.kt
index bbe30781..9e6ed506 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/VariableValueTypeTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/VariableValueTypeTest.kt
@@ -3,9 +3,7 @@ package org.hisp.dhis.rules
 import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.api.RuleEngine
-import org.hisp.dhis.rules.models.Rule
 import org.hisp.dhis.rules.api.RuleEngineContext
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
 import org.hisp.dhis.rules.models.*
 import kotlin.test.Test
 import kotlin.test.assertEquals
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/models/CalculatedValueTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/models/CalculatedValueTest.kt
index 714bb98b..7cc445b3 100644
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/models/CalculatedValueTest.kt
+++ b/src/commonTest/kotlin/org/hisp/dhis/rules/models/CalculatedValueTest.kt
@@ -3,7 +3,6 @@ package org.hisp.dhis.rules.models
 import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDate
 import org.hisp.dhis.rules.api.RuleEngine
-import org.hisp.dhis.rules.engine.DefaultRuleEngine
 import org.hisp.dhis.rules.api.RuleEngineContext
 import org.hisp.dhis.rules.utils.currentDate
 import kotlin.test.Test
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableAttributeTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableAttributeTest.kt
deleted file mode 100644
index bf0102e6..00000000
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableAttributeTest.kt
+++ /dev/null
@@ -1,16 +0,0 @@
-package org.hisp.dhis.rules.models
-
-import kotlin.test.Test
-import kotlin.test.assertEquals
-
-class RuleVariableAttributeTest {
-    @Test
-    fun createShouldPropagatePropertiesCorrectly() {
-        val ruleVariableAttribute = RuleVariableAttribute(
-            "test_variable", true, listOf(), "test_attribute", RuleValueType.NUMERIC
-        )
-        assertEquals("test_variable", ruleVariableAttribute.name)
-        assertEquals("test_attribute", ruleVariableAttribute.trackedEntityAttribute)
-        assertEquals(RuleValueType.NUMERIC, ruleVariableAttribute.trackedEntityAttributeType)
-    }
-}
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableCurrentEventTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableCurrentEventTest.kt
deleted file mode 100644
index 16081f56..00000000
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableCurrentEventTest.kt
+++ /dev/null
@@ -1,16 +0,0 @@
-package org.hisp.dhis.rules.models
-
-import kotlin.test.Test
-import kotlin.test.assertEquals
-
-class RuleVariableCurrentEventTest {
-    @Test
-    fun createShouldPropagatePropertiesCorrectly() {
-        val ruleVariableCurrentEvent = RuleVariableCurrentEvent(
-            "test_variable", true, ArrayList(), "test_dataelement", RuleValueType.NUMERIC
-        )
-        assertEquals("test_variable", ruleVariableCurrentEvent.name)
-        assertEquals("test_dataelement", ruleVariableCurrentEvent.dataElement)
-        assertEquals(RuleValueType.NUMERIC, ruleVariableCurrentEvent.dataElementType)
-    }
-}
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestEventTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestEventTest.kt
deleted file mode 100644
index 6ec9fae8..00000000
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestEventTest.kt
+++ /dev/null
@@ -1,15 +0,0 @@
-package org.hisp.dhis.rules.models
-
-import kotlin.test.Test
-import kotlin.test.assertEquals
-class RuleVariableNewestEventTest {
-    @Test
-    fun createShouldPropagatePropertiesCorrectly() {
-        val ruleVariableNewestEvent = RuleVariableNewestEvent(
-            "test_variable", true, ArrayList(), "test_dataelement", RuleValueType.NUMERIC
-        )
-        assertEquals("test_variable", ruleVariableNewestEvent.name)
-        assertEquals("test_dataelement", ruleVariableNewestEvent.dataElement)
-        assertEquals(RuleValueType.NUMERIC, ruleVariableNewestEvent.dataElementType)
-    }
-}
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestStageEventTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestStageEventTest.kt
deleted file mode 100644
index 60648a3d..00000000
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariableNewestStageEventTest.kt
+++ /dev/null
@@ -1,16 +0,0 @@
-package org.hisp.dhis.rules.models
-
-import kotlin.test.Test
-import kotlin.test.assertEquals
-class RuleVariableNewestStageEventTest {
-    @Test
-    fun createShouldPropagatePropertiesCorrectly() {
-        val ruleVariableNewestStageEvent = RuleVariableNewestStageEvent(
-            "test_variable", true, ArrayList(), "test_dataelement", RuleValueType.NUMERIC, "test_programstage"
-        )
-        assertEquals("test_variable", ruleVariableNewestStageEvent.name)
-        assertEquals("test_programstage", ruleVariableNewestStageEvent.programStage)
-        assertEquals("test_dataelement", ruleVariableNewestStageEvent.dataElement)
-        assertEquals(RuleValueType.NUMERIC, ruleVariableNewestStageEvent.dataElementType)
-    }
-}
diff --git a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariablePreviousEventTest.kt b/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariablePreviousEventTest.kt
deleted file mode 100644
index a48242e8..00000000
--- a/src/commonTest/kotlin/org/hisp/dhis/rules/models/RuleVariablePreviousEventTest.kt
+++ /dev/null
@@ -1,16 +0,0 @@
-package org.hisp.dhis.rules.models
-
-import kotlin.test.Test
-import kotlin.test.assertEquals
-
-class RuleVariablePreviousEventTest {
-    @Test
-    fun createShouldPropagatePropertiesCorrectly() {
-        val ruleVariablePreviousEvent = RuleVariablePreviousEvent(
-            "test_variable", true, ArrayList(), "test_dataelement", RuleValueType.NUMERIC
-        )
-        assertEquals("test_variable", ruleVariablePreviousEvent.name)
-        assertEquals("test_dataelement", ruleVariablePreviousEvent.dataElement)
-        assertEquals(RuleValueType.NUMERIC, ruleVariablePreviousEvent.dataElementType)
-    }
-}
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/DataItemJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/DataItemJs.kt
new file mode 100644
index 00000000..72f4b326
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/DataItemJs.kt
@@ -0,0 +1,15 @@
+package org.hisp.dhis.rules
+
+import org.hisp.dhis.rules.api.ItemValueType
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class DataItemJs(val displayName: String, val valueType: String){
+    init {
+        require(TYPES.contains(valueType)) { "ItemValueType type must be one of: $TYPES" }
+    }
+
+    companion object {
+        val TYPES = ItemValueType.entries.map { it.name } .toTypedArray()
+    }
+}
\ No newline at end of file
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleActionJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleActionJs.kt
new file mode 100644
index 00000000..b7a5c912
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleActionJs.kt
@@ -0,0 +1,11 @@
+package org.hisp.dhis.rules
+
+import org.hisp.dhis.lib.expression.js.Entry
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleActionJs(
+    val data: String?,
+    val type: String,
+    val values: Array<Entry<String, String>> = emptyArray()
+)
\ No newline at end of file
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleDataValueJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleDataValueJs.kt
new file mode 100644
index 00000000..268f71a7
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleDataValueJs.kt
@@ -0,0 +1,12 @@
+package org.hisp.dhis.rules
+
+import kotlinx.datetime.internal.JSJoda.Instant
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleDataValueJs(
+    val eventDate: Instant,
+    val programStage: String,
+    val dataElement: String,
+    val value: String
+)
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEffectJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEffectJs.kt
new file mode 100644
index 00000000..3cc61d55
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEffectJs.kt
@@ -0,0 +1,9 @@
+package org.hisp.dhis.rules
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleEffectJs(
+    val ruleId: String,
+    val ruleAction: RuleActionJs,
+    val data: String? = ""
+)
\ No newline at end of file
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEffectsJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEffectsJs.kt
new file mode 100644
index 00000000..6cd2aba4
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEffectsJs.kt
@@ -0,0 +1,19 @@
+package org.hisp.dhis.rules
+
+import org.hisp.dhis.rules.models.TrackerObjectType
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleEffectsJs(
+    val trackerObjectType: String,
+    val trackerObjectUid: String,
+    val ruleEffects: Array<RuleEffectJs>
+) {
+    init {
+        require(TYPES.contains(trackerObjectType)) { "trackerObjectType type must be one of: $TYPES" }
+    }
+
+    companion object {
+        val TYPES = TrackerObjectType.entries.map { it.name } .toTypedArray()
+    }
+}
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEngineContextJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEngineContextJs.kt
new file mode 100644
index 00000000..e9f37464
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEngineContextJs.kt
@@ -0,0 +1,12 @@
+package org.hisp.dhis.rules
+
+import org.hisp.dhis.lib.expression.js.Entry
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleEngineContextJs(
+    val rules: Array<RuleJs>,
+    val ruleVariables: Array<RuleVariableJs>,
+    val supplementaryData: Array<Entry<String, Array<String>>> = emptyArray(),
+    val constantsValues: Array<Entry<String, String>> = emptyArray()
+)
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEngineJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEngineJs.kt
new file mode 100644
index 00000000..f97aea95
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEngineJs.kt
@@ -0,0 +1,202 @@
+package org.hisp.dhis.rules
+
+import kotlinx.datetime.Instant
+import kotlinx.datetime.LocalDate
+import org.hisp.dhis.lib.expression.js.Entry
+import org.hisp.dhis.rules.api.DataItem
+import org.hisp.dhis.rules.api.ItemValueType
+import org.hisp.dhis.rules.api.RuleEngine
+import org.hisp.dhis.rules.api.RuleEngineContext
+import org.hisp.dhis.rules.models.*
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+class RuleEngineJs {
+    fun validate(expression: String, dataItemStore: Array<Entry<String, DataItemJs>>): RuleValidationResult{
+        return RuleEngine.getInstance().validate(expression, toMap(dataItemStore, {it}, ::toDataItemJava))
+    }
+    fun validateDataFieldExpression(expression: String, dataItemStore: Array<Entry<String, DataItemJs>>): RuleValidationResult{
+        return RuleEngine.getInstance().validateDataFieldExpression(expression, toMap(dataItemStore, {it}, ::toDataItemJava))
+    }
+    fun evaluateAll(enrollmentTarget: RuleEnrollmentJs?, eventsTarget: Array<RuleEventJs>, executionContext: RuleEngineContextJs): Array<RuleEffectsJs>{
+        return toRuleEffectsJsList(RuleEngine.getInstance().evaluateAll(toEnrollmentJava(enrollmentTarget),
+            eventsTarget.map(::toEventJava).toList(),
+            toRuleEngineContextJava(executionContext)))
+    }
+
+    fun evaluateEnrollment(target: RuleEnrollmentJs, ruleEvents: Array<RuleEventJs>, executionContext: RuleEngineContextJs): Array<RuleEffectJs>{
+        return RuleEngine.getInstance().evaluate(toEnrollmentJava(target)!!,
+                ruleEvents.map(::toEventJava).toList(),
+                toRuleEngineContextJava(executionContext))
+            .map(::toRuleEffectJs).toTypedArray()
+    }
+    fun evaluateEvent(target: RuleEventJs, ruleEnrollment: RuleEnrollmentJs?, ruleEvents: Array<RuleEventJs>, executionContext: RuleEngineContextJs): Array<RuleEffectJs>{
+        return RuleEngine.getInstance().evaluate(toEventJava(target),
+                toEnrollmentJava(ruleEnrollment),
+                ruleEvents.map(::toEventJava).toList(),
+                toRuleEngineContextJava(executionContext))
+            .map(::toRuleEffectJs).toTypedArray()
+    }
+
+    private fun <Kf, Vf, K, V> toMap(map: Array<Entry<Kf, Vf>>, key: (Kf) -> K, value: (Vf) -> V): Map<K, V> {
+        val res : MutableMap<K, V> = mutableMapOf()
+        map.forEach { e -> res[key(e.key)] = value(e.value) }
+        return res
+    }
+
+    private fun toDataItemJava(item: DataItemJs) : DataItem {
+        return DataItem(
+            valueType = ItemValueType.valueOf(item.valueType),
+            displayName = item.displayName
+        )
+    }
+
+    private fun toEnrollmentJava(enrollmentTarget: RuleEnrollmentJs?): RuleEnrollment? {
+        if(enrollmentTarget == null) return null
+
+        return RuleEnrollment(
+            enrollment = enrollmentTarget.enrollment,
+            programName = enrollmentTarget.programName,
+            incidentDate = LocalDate.fromEpochDays(enrollmentTarget.incidentDate.toEpochDay().toInt()),
+            enrollmentDate = LocalDate.fromEpochDays(enrollmentTarget.enrollmentDate.toEpochDay().toInt()),
+            status = RuleEnrollment.Status.valueOf(enrollmentTarget.status),
+            organisationUnit = enrollmentTarget.organisationUnit,
+            organisationUnitCode = enrollmentTarget.organisationUnitCode,
+            attributeValues = enrollmentTarget.attributeValues.toList()
+        )
+    }
+
+    private fun toEventJava(event: RuleEventJs): RuleEvent {
+        return RuleEvent(
+            event = event.event,
+            programStage = event.programStage,
+            programStageName = event.programStageName,
+            status = RuleEvent.Status.valueOf(event.status),
+            eventDate = Instant.fromEpochMilliseconds(event.eventDate.toEpochMilli().toLong()),
+            dueDate = toLocalDate(event.dueDate),
+            completedDate = toLocalDate(event.completedDate),
+            organisationUnit = event.organisationUnit,
+            organisationUnitCode = event.organisationUnitCode,
+            dataValues = event.dataValues.map(::toRuleDataValueJava).toList()
+        )
+    }
+
+    private fun toRuleJava(rule: RuleJs): Rule {
+        return Rule(
+            condition = rule.condition,
+            actions = rule.actions.map(::toRuleActionJava),
+            uid = rule.uid,
+            name = rule.name,
+            programStage = rule.programStage,
+            priority = rule.priority
+        )
+    }
+
+    private fun toRuleDataValueJava(ruleDataValue: RuleDataValueJs): RuleDataValue {
+        return RuleDataValue(
+            eventDate = Instant.fromEpochMilliseconds(ruleDataValue.eventDate.toEpochMilli().toLong()),
+            programStage = ruleDataValue.programStage,
+            dataElement = ruleDataValue.dataElement,
+            value = ruleDataValue.value
+        )
+    }
+
+    private fun toRuleActionJava(ruleAction: RuleActionJs): RuleAction {
+        return RuleAction(
+            data = ruleAction.data,
+            type = ruleAction.type,
+            values = toMap(ruleAction.values, {it}, {it})
+        )
+    }
+
+    private fun toRuleEngineContextJava(executionContext: RuleEngineContextJs): RuleEngineContext {
+        return RuleEngineContext(
+            rules = executionContext.rules.map(::toRuleJava),
+            supplementaryData = toMap(executionContext.supplementaryData, {it}, { v -> v.toList() }),
+            constantsValues = toMap(executionContext.constantsValues, {it}, {it}),
+            ruleVariables = executionContext.ruleVariables.map(::toRuleVariableJava)
+        )
+    }
+
+    private fun toRuleActionJs(ruleAction: RuleAction): RuleActionJs {
+        return RuleActionJs(
+            data = ruleAction.data,
+            type = ruleAction.type,
+            values = ruleAction.values.entries.map { e -> Entry(e.key, e.value) }.toTypedArray()
+        )
+    }
+
+    private fun toRuleEffectJs(ruleEffect: RuleEffect): RuleEffectJs {
+        return RuleEffectJs(
+            ruleId = ruleEffect.ruleId,
+            ruleAction = toRuleActionJs(ruleEffect.ruleAction),
+            data = ruleEffect.data
+        )
+    }
+
+    private fun toRuleEffectsJs(ruleEffects: RuleEffects): RuleEffectsJs {
+        return RuleEffectsJs(
+            trackerObjectType = ruleEffects.trackerObjectType.name,
+            trackerObjectUid = ruleEffects.trackerObjectUid,
+            ruleEffects = ruleEffects.ruleEffects.map(::toRuleEffectJs).toTypedArray()
+        )
+
+    }
+
+    private fun toRuleEffectsJsList(ruleEffects: List<RuleEffects>): Array<RuleEffectsJs> {
+        return ruleEffects.map(::toRuleEffectsJs).toTypedArray()
+    }
+
+    private fun toLocalDate(localDate: kotlinx.datetime.internal.JSJoda.LocalDate?): LocalDate? {
+        if (localDate == null) return null
+        return LocalDate.fromEpochDays(localDate.toEpochDay().toInt())
+    }
+
+    private fun toRuleVariableJava(ruleVariableJs: RuleVariableJs): RuleVariable {
+        return when(RuleVariableType.valueOf(ruleVariableJs.type)){
+            RuleVariableType.DATAELEMENT_NEWEST_EVENT_PROGRAM_STAGE -> RuleVariableNewestStageEvent(
+                name = ruleVariableJs.name,
+                useCodeForOptionSet = ruleVariableJs.useCodeForOptionSet,
+                options = ruleVariableJs.options.toList(),
+                field = ruleVariableJs.field,
+                fieldType = RuleValueType.valueOf(ruleVariableJs.fieldType),
+                programStage = ruleVariableJs.programStage ?: ""
+            )
+            RuleVariableType.DATAELEMENT_NEWEST_EVENT_PROGRAM -> RuleVariableNewestEvent(
+                name = ruleVariableJs.name,
+                useCodeForOptionSet = ruleVariableJs.useCodeForOptionSet,
+                options = ruleVariableJs.options.toList(),
+                field = ruleVariableJs.field,
+                fieldType = RuleValueType.valueOf(ruleVariableJs.fieldType)
+            )
+            RuleVariableType.DATAELEMENT_CURRENT_EVENT -> RuleVariableCurrentEvent(
+                name = ruleVariableJs.name,
+                useCodeForOptionSet = ruleVariableJs.useCodeForOptionSet,
+                options = ruleVariableJs.options.toList(),
+                field = ruleVariableJs.field,
+                fieldType = RuleValueType.valueOf(ruleVariableJs.fieldType)
+            )
+            RuleVariableType.DATAELEMENT_PREVIOUS_EVENT -> RuleVariablePreviousEvent(
+                name = ruleVariableJs.name,
+                useCodeForOptionSet = ruleVariableJs.useCodeForOptionSet,
+                options = ruleVariableJs.options.toList(),
+                field = ruleVariableJs.field,
+                fieldType = RuleValueType.valueOf(ruleVariableJs.fieldType)
+            )
+            RuleVariableType.CALCULATED_VALUE -> RuleVariableCalculatedValue(
+                name = ruleVariableJs.name,
+                useCodeForOptionSet = ruleVariableJs.useCodeForOptionSet,
+                options = ruleVariableJs.options.toList(),
+                field = ruleVariableJs.field,
+                fieldType = RuleValueType.valueOf(ruleVariableJs.fieldType)
+            )
+            RuleVariableType.TEI_ATTRIBUTE -> RuleVariableAttribute(
+                name = ruleVariableJs.name,
+                useCodeForOptionSet = ruleVariableJs.useCodeForOptionSet,
+                options = ruleVariableJs.options.toList(),
+                field = ruleVariableJs.field,
+                fieldType = RuleValueType.valueOf(ruleVariableJs.fieldType)
+            )
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEnrollmentJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEnrollmentJs.kt
new file mode 100644
index 00000000..e0db012c
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEnrollmentJs.kt
@@ -0,0 +1,16 @@
+package org.hisp.dhis.rules
+
+import org.hisp.dhis.rules.models.RuleAttributeValue
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleEnrollmentJs(
+    val enrollment: String,
+    val programName: String,
+    val incidentDate: kotlinx.datetime.internal.JSJoda.LocalDate,
+    val enrollmentDate: kotlinx.datetime.internal.JSJoda.LocalDate,
+    val status: String,
+    val organisationUnit: String,
+    val organisationUnitCode: String,
+    val attributeValues: Array<RuleAttributeValue>
+)
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEventJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEventJs.kt
new file mode 100644
index 00000000..26bba962
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleEventJs.kt
@@ -0,0 +1,19 @@
+package org.hisp.dhis.rules
+
+import kotlinx.datetime.internal.JSJoda.Instant
+import kotlinx.datetime.internal.JSJoda.LocalDate
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleEventJs(
+    val event: String,
+    val programStage: String,
+    val programStageName: String,
+    val status: String,
+    val eventDate: Instant,
+    val dueDate: LocalDate?,
+    val completedDate: LocalDate?,
+    val organisationUnit: String,
+    val organisationUnitCode: String?,
+    val dataValues: Array<RuleDataValueJs>
+)
\ No newline at end of file
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleJs.kt
new file mode 100644
index 00000000..dd09da2c
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleJs.kt
@@ -0,0 +1,12 @@
+package org.hisp.dhis.rules
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleJs(
+    val condition: String,
+    val actions: Array<RuleActionJs>,
+    val uid: String = "",
+    val name: String? = null,
+    val programStage: String? = null,
+    val priority: Int? = 0
+)
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleVariableJs.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleVariableJs.kt
new file mode 100644
index 00000000..1809d73d
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleVariableJs.kt
@@ -0,0 +1,26 @@
+package org.hisp.dhis.rules
+
+import org.hisp.dhis.rules.models.Option
+import org.hisp.dhis.rules.models.RuleValueType
+
+@JsExport
+@OptIn(ExperimentalJsExport::class)
+data class RuleVariableJs(
+    val type: String,
+    val name: String,
+    val useCodeForOptionSet: Boolean,
+    val options: Array<Option>,
+    val field: String,
+    val fieldType: String,
+    val programStage: String?
+){
+    init {
+        require(RULE_VALUE_TYPES.contains(fieldType)) { "RuleValueType type must be one of: $RULE_VALUE_TYPES" }
+        require(TYPES.contains(fieldType)) { "RuleVariableType type must be one of: $TYPES" }
+    }
+
+    companion object {
+        val RULE_VALUE_TYPES = RuleValueType.entries.map { it.name } .toTypedArray()
+        val TYPES = RuleVariableType.entries.map { it.name } .toTypedArray()
+    }
+}
diff --git a/src/jsMain/kotlin/org/hisp/dhis/rules/RuleVariableType.kt b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleVariableType.kt
new file mode 100644
index 00000000..3e97c3d1
--- /dev/null
+++ b/src/jsMain/kotlin/org/hisp/dhis/rules/RuleVariableType.kt
@@ -0,0 +1,10 @@
+package org.hisp.dhis.rules
+
+enum class RuleVariableType {
+    DATAELEMENT_NEWEST_EVENT_PROGRAM_STAGE,
+    DATAELEMENT_NEWEST_EVENT_PROGRAM,
+    DATAELEMENT_CURRENT_EVENT,
+    DATAELEMENT_PREVIOUS_EVENT,
+    CALCULATED_VALUE,
+    TEI_ATTRIBUTE;
+}
\ No newline at end of file