diff --git a/src/plugins/data/common/index_patterns/index_patterns/index_pattern.ts b/src/plugins/data/common/index_patterns/index_patterns/index_pattern.ts
index af9df448f6d93..45071b849cf67 100644
--- a/src/plugins/data/common/index_patterns/index_patterns/index_pattern.ts
+++ b/src/plugins/data/common/index_patterns/index_patterns/index_pattern.ts
@@ -87,7 +87,6 @@ export class IndexPattern implements IIndexPattern {
   private fieldFormats: FieldFormatsStartCommon;
   private fieldAttrs: FieldAttrs;
   private runtimeFieldMap: Record<string, RuntimeField>;
-  private runtimeCompositeMap: Record<string, RuntimeComposite>;
 
   /**
    * prevents errors when index pattern exists before indices
@@ -131,7 +130,6 @@ export class IndexPattern implements IIndexPattern {
     this.intervalName = spec.intervalName;
     this.allowNoIndex = spec.allowNoIndex || false;
     this.runtimeFieldMap = spec.runtimeFieldMap || {};
-    this.runtimeCompositeMap = spec.runtimeCompositeMap || {};
   }
 
   /**
@@ -238,7 +236,6 @@ export class IndexPattern implements IIndexPattern {
       type: this.type,
       fieldFormats: this.fieldFormatMap,
       runtimeFieldMap: this.runtimeFieldMap,
-      runtimeCompositeMap: this.runtimeCompositeMap,
       fieldAttrs: this.fieldAttrs,
       intervalName: this.intervalName,
       allowNoIndex: this.allowNoIndex,
@@ -349,7 +346,6 @@ export class IndexPattern implements IIndexPattern {
       : JSON.stringify(this.fieldFormatMap);
     const fieldAttrs = this.getFieldAttrs();
     const runtimeFieldMap = this.runtimeFieldMap;
-    const runtimeCompositeMap = this.runtimeCompositeMap;
 
     return {
       fieldAttrs: fieldAttrs ? JSON.stringify(fieldAttrs) : undefined,
@@ -363,7 +359,6 @@ export class IndexPattern implements IIndexPattern {
       typeMeta: JSON.stringify(this.typeMeta ?? {}),
       allowNoIndex: this.allowNoIndex ? this.allowNoIndex : undefined,
       runtimeFieldMap: runtimeFieldMap ? JSON.stringify(runtimeFieldMap) : undefined,
-      runtimeCompositeMap: runtimeCompositeMap ? JSON.stringify(runtimeCompositeMap) : undefined,
     };
   }
 
@@ -393,13 +388,14 @@ export class IndexPattern implements IIndexPattern {
    * @param enhancedRuntimeField Runtime field definition
    */
   addRuntimeField(name: string, enhancedRuntimeField: EnhancedRuntimeField): IndexPatternField {
-    const { type, script, parentComposite, customLabel, format, popularity } = enhancedRuntimeField;
+    const { type, script, customLabel, format, popularity } = enhancedRuntimeField;
 
-    const runtimeField: RuntimeField = { type, script, parentComposite };
+    const runtimeField: RuntimeField = { type, script };
     this.runtimeFieldMap[name] = runtimeField;
 
     // Create the field if it does not exist or update an existing one
     let createdField: IndexPatternField | undefined;
+    // instead of modifying the field array, lets recreate it - not sure if this will work
     const existingField = this.getFieldByName(name);
     if (existingField) {
       existingField.runtimeField = runtimeField;
@@ -466,9 +462,11 @@ export class IndexPattern implements IIndexPattern {
     const existingField = this.getFieldByName(name);
 
     if (existingField) {
-      if (existingField.runtimeField?.parentComposite !== undefined) {
+      if (existingField.runtimeField?.type === 'composite') {
         throw new Error(
-          `Can't remove runtime field ["${name}"] as it belongs to the composite runtime ["${existingField.runtimeField.parentComposite}"]`
+          // todo
+          `Can't remove runtime field ["${name}"] as it belongs to the composite runtime"]`
+          // `Can't remove runtime field ["${name}"] as it belongs to the composite runtime ["${existingField.runtimeField.parentComposite}"]`
         );
       }
 
@@ -482,53 +480,6 @@ export class IndexPattern implements IIndexPattern {
     delete this.runtimeFieldMap[name];
   }
 
-  /**
-   * Create a runtime composite and add its subFields to the index pattern fields list
-   * @param name - The runtime composite name
-   * @param runtimeComposite - The runtime composite definition
-   */
-  addRuntimeComposite(
-    name: string,
-    runtimeComposite: RuntimeCompositeWithSubFields
-  ): IndexPatternField[] {
-    if (!runtimeComposite.subFields || Object.keys(runtimeComposite.subFields).length === 0) {
-      throw new Error(`Can't save runtime composite [name = ${name}] without subfields.`);
-    }
-
-    // We first remove the runtime composite with the same name which will remove all of its subFields.
-    // This guarantees that we don't leave behind orphan runtime fields (with a "compositeParent").
-    this.removeRuntimeComposite(name);
-
-    const { script, subFields } = runtimeComposite;
-
-    const fieldsCreated: IndexPatternField[] = [];
-
-    for (const [subFieldName, subField] of Object.entries(subFields)) {
-      const field = this.addRuntimeField(`${name}.${subFieldName}`, {
-        ...subField,
-        parentComposite: name,
-      });
-      fieldsCreated.push(field);
-    }
-
-    this.runtimeCompositeMap[name] = {
-      name,
-      script,
-      // We only need to keep a reference of the subFields names
-      subFields: Object.keys(subFields),
-    };
-
-    return fieldsCreated;
-  }
-
-  /**
-   * Returns runtime composite if exists
-   * @param name
-   */
-  getRuntimeComposite(name: string): RuntimeComposite | null {
-    return this.runtimeCompositeMap[name] ?? null;
-  }
-
   /**
    * Returns runtime composite (if exists) with its subFields
    * @param name
@@ -568,23 +519,6 @@ export class IndexPattern implements IIndexPattern {
     };
   }
 
-  /**
-   * Remove a runtime composite with its associated subFields
-   * @param name - Runtime composite name to remove
-   */
-  removeRuntimeComposite(name: string) {
-    const existingRuntimeComposite = this.getRuntimeComposite(name);
-
-    if (!!existingRuntimeComposite) {
-      // Remove all subFields
-      for (const subFieldName of existingRuntimeComposite.subFields) {
-        this.removeRuntimeField(`${name}.${subFieldName}`);
-      }
-
-      delete this.runtimeCompositeMap[name];
-    }
-  }
-
   /**
    * Get formatter for a given field name. Return undefined if none exists
    * @param field
diff --git a/src/plugins/data/common/index_patterns/types.ts b/src/plugins/data/common/index_patterns/types.ts
index 632559f4b84c0..67e7eb315752c 100644
--- a/src/plugins/data/common/index_patterns/types.ts
+++ b/src/plugins/data/common/index_patterns/types.ts
@@ -17,7 +17,10 @@ import { FieldFormat } from '../../../field_formats/common';
 
 export type FieldFormatMap = Record<string, SerializedFieldFormat>;
 
-export type RuntimeType = estypes.MappingRuntimeFieldType | 'composite';
+type CompositeRuntimeType = 'composite';
+type SimpleRuntimeType = estypes.MappingRuntimeFieldType;
+
+export type RuntimeType = SimpleRuntimeType | CompositeRuntimeType;
 
 /**
  * The RuntimeField that will be sent in the ES Query "runtime_mappings" object
@@ -35,15 +38,27 @@ export interface ESRuntimeField extends Omit<estypes.MappingRuntimeField, 'type'
   >;
 }
 
+export interface SimpleRuntimeField {
+  type: SimpleRuntimeType;
+  script?: {
+    source: string;
+  };
+}
+
+export interface CompositeRuntimeField {
+  type: CompositeRuntimeType;
+  script: {
+    source: string;
+  };
+  fields: Record<string, { type: SimpleRuntimeType }>;
+}
+
 /**
  * The RuntimeField which is saved in the Data View saved object. We extend it to
  * keep a reference to a possible parent composite object.
  * To simplify the consuming code we enforce the script to be `InlineScript` type (and not also `string`)
  */
-export interface RuntimeField extends Omit<ESRuntimeField, 'script'> {
-  script?: estypes.InlineScript;
-  parentComposite?: string;
-}
+export type RuntimeField = SimpleRuntimeField | CompositeRuntimeField;
 
 /**
  * Runtime fields are like other fields when it comes to formatting or giving