diff --git a/README.md b/README.md
index 1cc5ebbab..7444c830d 100644
--- a/README.md
+++ b/README.md
@@ -642,21 +642,41 @@ retain("<sourceField_1>"[, ...])
 
 ##### `set_array`
 
-_Currently alias for [`add_array`](#add_array)._
+Creates a new array (with optional values), provided that the intermediate structures (i.e. parent fields) exist. To create any missing intermediate structures, use [`add_array`](#add_array) instead.
 
-We advise you to use [`add_array`](#add_array) instead of `set_array` due to changing behaviour in an upcoming release. For more information see: [#309](https://github.com/metafacture/metafacture-fix/issues/309)
+```perl
+set_array("<targetFieldName>")
+set_array("<targetFieldName>", "<value_1>"[, ...])
+```
+
+[Example in Playground](https://metafacture.org/playground/?example=set_array)
+
+[Java Code](https://github.com/search?type=code&q=repo:metafacture/metafacture-core+path:FixMethod.java+"+set_array+{")
 
 ##### `set_field`
 
-_Currently alias for [`add_field`](#add_field)._
+Creates a field with a defined value, provided that the intermediate structures (i.e. parent fields) exist. To create any missing intermediate structures, use [`add_field`](#add_field) instead.
+
+```perl
+set_field("<targetFieldName>", "<fieldValue>")
+```
+
+[Example in Playground](https://metafacture.org/playground/?example=set_field)
 
-We advise you to use [`add_field`](#add_field) instead of `set_field` due to changing behaviour in an upcoming release. For more information see: [#309](https://github.com/metafacture/metafacture-fix/issues/309)
+[Java Code](https://github.com/search?type=code&q=repo:metafacture/metafacture-core+path:FixMethod.java+"+set_field+{")
 
 ##### `set_hash`
 
-_Currently alias for [`add_hash`](#add_hash)._
+Creates a new hash (with optional values), provided that the intermediate structures (i.e. parent fields) exist. To create any missing intermediate structures, use [`add_hash`](#add_hash) instead.
+
+```perl
+set_hash("<targetFieldName>")
+set_hash("<targetFieldName>", "subfieldName": "<subfieldValue>"[, ...])
+```
+
+[Example in Playground](https://metafacture.org/playground/?example=set_hash)
 
-We advise you to use [`add_hash`](#add_hash) instead of `set_hash` due to changing behaviour in an upcoming release. For more information see: [#309](https://github.com/metafacture/metafacture-fix/issues/309)
+[Java Code](https://github.com/search?type=code&q=repo:metafacture/metafacture-core+path:FixMethod.java+"+set_hash+{")
 
 ##### `timestamp`
 
diff --git a/metafix/src/main/java/org/metafacture/metafix/FixMethod.java b/metafix/src/main/java/org/metafacture/metafix/FixMethod.java
index b06352338..c7132e37d 100644
--- a/metafix/src/main/java/org/metafacture/metafix/FixMethod.java
+++ b/metafix/src/main/java/org/metafacture/metafix/FixMethod.java
@@ -170,7 +170,7 @@ public void apply(final Metafix metafix, final Record record, final List<String>
             final String field = params.get(0);
             final Value newValue = newArray(params.subList(1, params.size()).stream().map(Value::new));
             record.set(field, newValue);
-            newValue.asArray().forEach(value -> value.withPathSet(newValue.getPath() + "." + value.getPath()));
+            newValue.asArray().forEach(value -> value.withPathSet(newValue.getPath() + Value.FIELD_PATH_SEPARATOR + value.getPath()));
         }
     },
     add_field {
@@ -408,19 +408,25 @@ public void apply(final Metafix metafix, final Record record, final List<String>
     set_array {
         @Override
         public void apply(final Metafix metafix, final Record record, final List<String> params, final Map<String, String> options) {
-            add_array.apply(metafix, record, params, options);
+            if (parentFieldExists(record, params.get(0))) {
+                add_array.apply(metafix, record, params, options);
+            }
         }
     },
     set_field {
         @Override
         public void apply(final Metafix metafix, final Record record, final List<String> params, final Map<String, String> options) {
-            add_field.apply(metafix, record, params, options);
+            if (parentFieldExists(record, params.get(0))) {
+                add_field.apply(metafix, record, params, options);
+            }
         }
     },
     set_hash {
         @Override
         public void apply(final Metafix metafix, final Record record, final List<String> params, final Map<String, String> options) {
-            add_hash.apply(metafix, record, params, options);
+            if (parentFieldExists(record, params.get(0))) {
+                add_hash.apply(metafix, record, params, options);
+            }
         }
     },
     timestamp {
diff --git a/metafix/src/main/java/org/metafacture/metafix/FixPath.java b/metafix/src/main/java/org/metafacture/metafix/FixPath.java
index 0b96b8410..497706d1c 100644
--- a/metafix/src/main/java/org/metafacture/metafix/FixPath.java
+++ b/metafix/src/main/java/org/metafacture/metafix/FixPath.java
@@ -29,14 +29,22 @@
  * With all get/set/update/create/delete logic collected here.
  *
  * @author Fabian Steeg (fsteeg)
- *
  */
-/*package-private*/ class FixPath {
+public class FixPath {
 
     private static final String ASTERISK = "*";
+
+    private static final String INDEX_SUBPATH_PATTERN = Value.FIELD_PATH_SEPARATOR_PATTERN + "\\d" + Value.FIELD_PATH_SEPARATOR_PATTERN;
+    private static final String ASTERISK_SUBPATH = Value.FIELD_PATH_SEPARATOR + ASTERISK + Value.FIELD_PATH_SEPARATOR;
+
     private String[] path;
 
-    /*package-private*/ FixPath(final String path) {
+    /**
+     * Creates an instance of {@link FixPath} based on the given path string.
+     *
+     * @param path the path string
+     */
+    public FixPath(final String path) {
         this(Value.split(path));
     }
 
@@ -111,7 +119,7 @@ private Value findInValue(final Value value, final String[] p) {
 
     @Override
     public String toString() {
-        return String.join(".", path);
+        return String.join(Value.FIELD_PATH_SEPARATOR, path);
     }
 
     /*package-private*/ int size() {
@@ -141,7 +149,9 @@ else if (value.getPath() != null && hasWildcard()) {
     }
 
     private boolean matches(final String thatPath) {
-        return thatPath != null && thatPath.replaceAll("\\.\\d+\\.", ".*.").equals(String.join(".", this.path));
+        return thatPath != null && thatPath
+            .replaceAll(INDEX_SUBPATH_PATTERN, ASTERISK_SUBPATH)
+            .equals(String.join(Value.FIELD_PATH_SEPARATOR, this.path));
     }
 
     private String[] replaceInPath(final String find, final int i) {
@@ -299,9 +309,29 @@ private Value insertInto(final Value value, final InsertMode mode, final Value n
         }
     }
 
+    /**
+     * Checks whether the given field is adding to an array.
+     *
+     * @param field the field
+     *
+     * @return true if the given field is adding to an array
+     */
+    public static boolean isAddingToArray(final String field) {
+        return field.equals(ReservedField.$prepend.name()) || field.equals(ReservedField.$append.name());
+    }
+
+    /**
+     * Checks whether any of the path segments are adding to an array.
+     *
+     * @return true if any of the path segments are adding to an array
+     */
+    public boolean isAddingToArray() {
+        return Arrays.stream(path).anyMatch(FixPath::isAddingToArray);
+    }
+
     private Value getContainerValue(final Hash hash, final String field, final String newPath, final String nextField) {
         Value result = hash.get(field);
-        final boolean isAddingToArray = nextField.equals(ReservedField.$prepend.name()) || nextField.equals(ReservedField.$append.name());
+        final boolean isAddingToArray = isAddingToArray(nextField);
         if (result == null) {
             result = (isAddingToArray ? Value.newArray() : Value.newHash()).withPathSet(newPath);
             hash.put(field, result);
@@ -320,6 +350,15 @@ private String[] tail(final String[] fields) {
         return Arrays.copyOfRange(fields, 1, fields.length);
     }
 
+    /**
+     * Creates an instance of {@link FixPath} based on the parent path.
+     *
+     * @return an instance of {@link FixPath}, or {@code null} if already at the top level
+     */
+    public FixPath getParentPath() {
+        return path.length > 1 ? new FixPath(Arrays.copyOfRange(path, 0, path.length - 1)) : null;
+    }
+
     private enum ReservedField {
         $prepend, $append, $first, $last;
 
diff --git a/metafix/src/main/java/org/metafacture/metafix/Value.java b/metafix/src/main/java/org/metafacture/metafix/Value.java
index 5f97c4ac7..5cca2c488 100644
--- a/metafix/src/main/java/org/metafacture/metafix/Value.java
+++ b/metafix/src/main/java/org/metafacture/metafix/Value.java
@@ -52,7 +52,8 @@
  */
 public class Value implements JsonValue { // checkstyle-disable-line ClassDataAbstractionCoupling
 
-    private static final String FIELD_PATH_SEPARATOR = "\\.";
+    public static final String FIELD_PATH_SEPARATOR = ".";
+    /*package-private*/ static final String FIELD_PATH_SEPARATOR_PATTERN = Pattern.quote(FIELD_PATH_SEPARATOR);
 
     private final Array array;
     private final Hash hash;
@@ -409,7 +410,7 @@ public void toJson(final JsonGenerator jsonGenerator) {
     }
 
     /*package-private*/ static String[] split(final String fieldPath) {
-        return fieldPath.split(FIELD_PATH_SEPARATOR);
+        return fieldPath.split(FIELD_PATH_SEPARATOR_PATTERN);
     }
 
     /**
@@ -431,7 +432,7 @@ private Value withPathAppend(final int i) {
     }
 
     private Value withPathAppend(final String field) {
-        return withPathSet(path == null || path.isEmpty() ? field : path + "." + field);
+        return withPathSet(path == null || path.isEmpty() ? field : path + FIELD_PATH_SEPARATOR + field);
     }
 
     /*package-private*/ Value copy() {
@@ -574,7 +575,7 @@ protected <T> Map<T, Collection<String>> retainFields(final Collection<String> f
             final Map<T, Collection<String>> retainFields = new HashMap<>();
 
             fields.forEach(p -> {
-                final String[] parts = p.split(FIELD_PATH_SEPARATOR, 2);
+                final String[] parts = p.split(FIELD_PATH_SEPARATOR_PATTERN, 2);
 
                 function.apply(parts[0]).forEach(f -> {
                     final Collection<String> retainNested = retainFields.computeIfAbsent(f, k -> new HashSet<>());
diff --git a/metafix/src/main/java/org/metafacture/metafix/api/FixFunction.java b/metafix/src/main/java/org/metafacture/metafix/api/FixFunction.java
index 4fb7891d6..f3033513f 100644
--- a/metafix/src/main/java/org/metafacture/metafix/api/FixFunction.java
+++ b/metafix/src/main/java/org/metafacture/metafix/api/FixFunction.java
@@ -18,6 +18,7 @@
 
 import org.metafacture.framework.StandardEventNames;
 import org.metafacture.io.ObjectWriter;
+import org.metafacture.metafix.FixPath;
 import org.metafacture.metafix.Metafix;
 import org.metafacture.metafix.Record;
 import org.metafacture.metafix.Value;
@@ -194,4 +195,17 @@ default Stream<Value> flatten(final Stream<Value> stream) {
         ));
     }
 
+    /**
+     * Checks whether the given field's parent field exists in the record.
+     *
+     * @param record the record
+     * @param field the field
+     *
+     * @return true if the given field's parent field exists in the record
+     */
+    default boolean parentFieldExists(final Record record, final String field) {
+        final FixPath parentPath = new FixPath(field).getParentPath();
+        return parentPath == null || !parentPath.isAddingToArray() && record.containsPath(parentPath.toString());
+    }
+
 }
diff --git a/metafix/src/test/java/org/metafacture/metafix/MetafixBindTest.java b/metafix/src/test/java/org/metafacture/metafix/MetafixBindTest.java
index 3527a54f3..6af9477a4 100644
--- a/metafix/src/test/java/org/metafacture/metafix/MetafixBindTest.java
+++ b/metafix/src/test/java/org/metafacture/metafix/MetafixBindTest.java
@@ -810,7 +810,7 @@ public void shouldDoListAsWithMultipleListsOfDifferentSizes() {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                 "set_array('sourceOrga[]')",
                 "do list_as(orgId: 'ccm:university[]', orgName: 'ccm:university_DISPLAYNAME[]', orgLoc: 'ccm:university_LOCATION[]')",
-                "  set_hash('sourceOrga[].$append')",
+                "  add_hash('sourceOrga[].$append')",
                 "  copy_field(orgId, 'sourceOrga[].$last.id')",
                 "  copy_field(orgName, 'sourceOrga[].$last.name')",
                 "  copy_field(orgLoc, 'sourceOrga[].$last.location')",
diff --git a/metafix/src/test/java/org/metafacture/metafix/MetafixLookupTest.java b/metafix/src/test/java/org/metafacture/metafix/MetafixLookupTest.java
index 24c26f501..53298e0e5 100644
--- a/metafix/src/test/java/org/metafacture/metafix/MetafixLookupTest.java
+++ b/metafix/src/test/java/org/metafacture/metafix/MetafixLookupTest.java
@@ -994,9 +994,9 @@ public void shouldLookupInCopiedNestedArraysCreatedWithPrepend() {
     private void shouldLookupInCopiedNestedArraysCreatedWith(final String reservedField) {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                 "put_map('rswk-indicator', s: 'SubjectHeading')",
-                "set_array('subject[]')",
-                "set_array('subject[]." + reservedField + ".componentList[]')",
-                "set_array('subject[].$last.componentList[]." + reservedField + ".type[]')",
+                "add_array('subject[]')",
+                "add_array('subject[]." + reservedField + ".componentList[]')",
+                "add_array('subject[].$last.componentList[]." + reservedField + ".type[]')",
                 "do list(path: 'D', 'var': '$i')",
                 "  copy_field('$i', 'subject[].$last.componentList[].$last.type[]." + reservedField + "')",
                 "end",
diff --git a/metafix/src/test/java/org/metafacture/metafix/MetafixMethodTest.java b/metafix/src/test/java/org/metafacture/metafix/MetafixMethodTest.java
index 7f0b94744..46ea82aca 100644
--- a/metafix/src/test/java/org/metafacture/metafix/MetafixMethodTest.java
+++ b/metafix/src/test/java/org/metafacture/metafix/MetafixMethodTest.java
@@ -2818,11 +2818,9 @@ public void addFieldWithReplaceAllArray() {
     private void addFieldWithReplaceAllArray(final boolean replaceAll) {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                 "do list(path: 'contribution[]', 'var': '$i')",
-                "  set_array('$i.agent.altLabel[]')",
                 "  add_field('$i.agent.altLabel[].$append', 'contribution')",
                 "end",
                 "do list(path: 'subject[]', 'var': '$i')",
-                "  set_array('$i.altLabel[]')",
                 "  add_field('$i.altLabel[].$append', 'subject')",
                 "end",
                 replaceAll ? "replace_all('contribution[].*.agent.altLabel[].*', 't', '')" : "",
@@ -2875,10 +2873,10 @@ public void setArrayWithReplaceAll() {
     private void setArrayWithReplaceAll(final boolean replaceAll) {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                 "do list(path: 'contribution[]', 'var': '$i')",
-                "  set_array('$i.agent.altLabel[]', 'contribution')",
+                "  add_array('$i.agent.altLabel[]', 'contribution')",
                 "end",
                 "do list(path: 'subject[]', 'var': '$i')",
-                "  set_array('$i.altLabel[]', 'subject')",
+                "  add_array('$i.altLabel[]', 'subject')",
                 "end",
                 replaceAll ? "replace_all('contribution[].*.agent.altLabel[].*', 't', '')" : "",
                 replaceAll ? "replace_all('subject[].*.altLabel[].*', 't', '')" : ""
@@ -2930,11 +2928,9 @@ public void copyFieldWithReplaceAllArray() {
     private void copyFieldWithReplaceAllArray(final boolean replaceAll) {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                 "do list(path: 'contribution[]', 'var': '$i')",
-                "  set_array('$i.agent.altLabel[]')",
                 "  copy_field('$i.label', '$i.agent.altLabel[].$append')",
                 "end",
                 "do list(path: 'subject[]', 'var': '$i')",
-                "  set_array('$i.altLabel[]')",
                 "  copy_field('$i.label', '$i.altLabel[].$append')",
                 "end",
                 replaceAll ? "replace_all('contribution[].*.agent.altLabel[].*', 't', '')" : "",
@@ -2987,11 +2983,9 @@ public void pasteWithReplaceAll() {
     private void pasteWithReplaceAll(final boolean replaceAll) {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                 "do list(path: 'contribution[]', 'var': '$i')",
-                "  set_array('$i.agent.altLabel[]')",
                 "  paste('$i.agent.altLabel[].$append', '$i.label', '~!')",
                 "end",
                 "do list(path: 'subject[]', 'var': '$i')",
-                "  set_array('$i.altLabel[]')",
                 "  paste('$i.altLabel[].$append', '$i.label', '~!')",
                 "end",
                 replaceAll ? "replace_all('contribution[].*.agent.altLabel[].*', ' !', '')" : "",
diff --git a/metafix/src/test/java/org/metafacture/metafix/MetafixRecordTest.java b/metafix/src/test/java/org/metafacture/metafix/MetafixRecordTest.java
index 31bfab6f3..e0642c4f4 100644
--- a/metafix/src/test/java/org/metafacture/metafix/MetafixRecordTest.java
+++ b/metafix/src/test/java/org/metafacture/metafix/MetafixRecordTest.java
@@ -164,10 +164,10 @@ public void entitiesPassThroughRepeatNestedEntity() {
     }
 
     @Test
-    public void setEmpty() {
+    public void addEmpty() {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
-                "set_field('my.nested.name','patrick')",
-                "set_field('your.nested.name','nicolas')"),
+                "add_field('my.nested.name','patrick')",
+                "add_field('your.nested.name','nicolas')"),
             i -> {
                 i.startRecord("1");
                 i.endRecord();
@@ -185,6 +185,20 @@ public void setEmpty() {
             });
     }
 
+    @Test
+    public void setEmpty() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_field('my.nested.name','patrick')",
+                "set_field('your.nested.name','nicolas')"),
+            i -> {
+                i.startRecord("1");
+                i.endRecord();
+            }, (o, f) -> {
+                o.get().startRecord("1");
+                o.get().endRecord();
+            });
+    }
+
     @Test
     public void setExisting() {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
@@ -1965,6 +1979,424 @@ public void setHashReplaceExisting() {
             });
     }
 
+    @Test
+    public void addArrayAppend() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "add_array('array[].$append')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().startEntity("2[]");
+                f.apply(2).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void addArrayAppendNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "add_array('array[].$append.test[]')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().startEntity("2");
+                o.get().startEntity("test[]");
+                f.apply(3).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setArrayAppend() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_array('array[].$append')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().startEntity("2[]");
+                f.apply(2).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setArrayAppendNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_array('array[].$append.test[]')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            o -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setArrayLast() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_array('array[].$last')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().startEntity("1[]");
+                f.apply(2).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setArrayLastNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_array('array[].$last.test[]')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.startEntity("1");
+                i.endEntity();
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().startEntity("1");
+                o.get().startEntity("test[]");
+                f.apply(3).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void addFieldAppend() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "add_field('array[].$append', 'test')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            o -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().literal("2", "test");
+                o.get().endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void addFieldAppendNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "add_field('array[].$append.test', 'bar')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().startEntity("2");
+                o.get().literal("test", "bar");
+                f.apply(2).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setFieldAppend() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_field('array[].$append', 'test')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            o -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().literal("2", "test");
+                o.get().endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setFieldAppendNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_field('array[].$append.test', 'bar')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            o -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setFieldLast() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_field('array[].$last', 'test')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            o -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "test");
+                o.get().endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setFieldLastNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_field('array[].$last.test', 'baz')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.startEntity("1");
+                i.literal("foo", "bar");
+                i.endEntity();
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().startEntity("1");
+                o.get().literal("foo", "bar");
+                o.get().literal("test", "baz");
+                f.apply(2).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void addHashAppend() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "add_hash('array[].$append')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().startEntity("2");
+                f.apply(2).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void addHashAppendNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "add_hash('array[].$append.test')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().startEntity("2");
+                o.get().startEntity("test");
+                f.apply(3).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setHashAppend() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_hash('array[].$append')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().startEntity("2");
+                f.apply(2).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setHashAppendNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_hash('array[].$append.test')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            o -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().literal("1", "foo");
+                o.get().endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setHashLast() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_hash('array[].$last')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.literal("1", "foo");
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().startEntity("1");
+                f.apply(2).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
+    @Test
+    public void setHashLastNested() {
+        MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
+                "set_hash('array[].$last.test')"
+            ),
+            i -> {
+                i.startRecord("1");
+                i.startEntity("array[]");
+                i.startEntity("1");
+                i.literal("foo", "bar");
+                i.endEntity();
+                i.endEntity();
+                i.endRecord();
+            },
+            (o, f) -> {
+                o.get().startRecord("1");
+                o.get().startEntity("array[]");
+                o.get().startEntity("1");
+                o.get().literal("foo", "bar");
+                o.get().startEntity("test");
+                f.apply(3).endEntity();
+                o.get().endRecord();
+            }
+        );
+    }
+
     @Test
     public void paste() {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
@@ -2435,7 +2867,7 @@ public void appendArray() {
     public void mixedArray() {
         MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                 "set_array('@context[]', 'https://w3id.org/kim/lrmi-profile/draft/context.jsonld')",
-                "set_hash('@context[].$append', '@language': 'de')"),
+                "add_hash('@context[].$append', '@language': 'de')"),
             i -> {
                 i.startRecord("1");
                 i.endRecord();
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/lookup/fromXml/toJson/lookupInDeeplyNestedArrayOfObjects/test.fix b/metafix/src/test/resources/org/metafacture/metafix/integration/lookup/fromXml/toJson/lookupInDeeplyNestedArrayOfObjects/test.fix
index 6a9c42c5a..5775c303d 100644
--- a/metafix/src/test/resources/org/metafacture/metafix/integration/lookup/fromXml/toJson/lookupInDeeplyNestedArrayOfObjects/test.fix
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/lookup/fromXml/toJson/lookupInDeeplyNestedArrayOfObjects/test.fix
@@ -1,11 +1,11 @@
 put_map("rswk-indicator", s: "SubjectHeading")
 
 if exists("6890?")
-  set_array("subject[].$append.type[]", "ComplexSubject")
+  add_array("subject[].$append.type[]", "ComplexSubject")
   set_array("subject[].$last.label")
   set_array("subject[].$last.componentList[]")
   do list(path: "6890?", "var": "$i")
-    set_array("subject[].$last.componentList[].$append.type[]")
+    add_array("subject[].$last.componentList[].$append.type[]")
     do list(path: "$i.D", "var": "$k")
       copy_field("$k", "subject[].$last.componentList[].$last.type[].$append")
     end
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/method/fromXml/toJson/replace_toUpper/test.fix b/metafix/src/test/resources/org/metafacture/metafix/integration/method/fromXml/toJson/replace_toUpper/test.fix
index 6bc9cbcdc..9b6c18bbb 100644
--- a/metafix/src/test/resources/org/metafacture/metafix/integration/method/fromXml/toJson/replace_toUpper/test.fix
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/method/fromXml/toJson/replace_toUpper/test.fix
@@ -1,5 +1,5 @@
 do list(path: "700[01] ", "var": "$i")
-  set_hash("contribution[].$append.agent")
+  add_hash("contribution[].$append.agent")
   copy_field("$i.a", "contribution[].$last.agent.label")
 end
 
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/method/fromXml/toJson/replace_toUpperStrictnessHandlesProcessExceptions/test.fix b/metafix/src/test/resources/org/metafacture/metafix/integration/method/fromXml/toJson/replace_toUpperStrictnessHandlesProcessExceptions/test.fix
index 6bc9cbcdc..9b6c18bbb 100644
--- a/metafix/src/test/resources/org/metafacture/metafix/integration/method/fromXml/toJson/replace_toUpperStrictnessHandlesProcessExceptions/test.fix
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/method/fromXml/toJson/replace_toUpperStrictnessHandlesProcessExceptions/test.fix
@@ -1,5 +1,5 @@
 do list(path: "700[01] ", "var": "$i")
-  set_hash("contribution[].$append.agent")
+  add_hash("contribution[].$append.agent")
   copy_field("$i.a", "contribution[].$last.agent.label")
 end
 
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/expected.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/expected.json
new file mode 100644
index 000000000..1a843afd0
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/expected.json
@@ -0,0 +1,18 @@
+{
+  "animals" : [ {
+    "name" : "Jake",
+    "type" : "dog"
+  }, {
+    "name" : "Blacky",
+    "type" : "bird"
+  } ],
+  "animals_2" : [ {
+    "name" : "Jake",
+    "type" : "dog"
+  }, {
+    "name" : "Blacky",
+    "type" : "bird"
+  }, {
+    "test" : [ "test", "test", "test" ]
+  } ]
+}
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/input.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/input.json
new file mode 100644
index 000000000..f4640bcdb
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/input.json
@@ -0,0 +1,16 @@
+{
+  "animals" : [ {
+    "name" : "Jake",
+    "type" : "dog"
+  }, {
+    "name" : "Blacky",
+    "type" : "bird"
+  } ],
+  "animals_2" : [ {
+    "name" : "Jake",
+    "type" : "dog"
+  }, {
+    "name" : "Blacky",
+    "type" : "bird"
+  } ]
+}
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/test.fix b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/test.fix
new file mode 100644
index 000000000..4d1b7dd6d
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/test.fix
@@ -0,0 +1 @@
+add_array("animals_2[].$append.test[]", "test", "test", "test")
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/test.flux b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/test.flux
new file mode 100644
index 000000000..7c3575fac
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayIntoArrayOfObjectsWithAppend/test.flux
@@ -0,0 +1,8 @@
+FLUX_DIR + "input.json"
+|open-file
+|as-records
+|decode-json
+|fix(FLUX_DIR + "test.fix")
+|encode-json(prettyPrinting="true")
+|write(FLUX_DIR + "output-metafix.json")
+;
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/expected.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/expected.json
new file mode 100644
index 000000000..b2777dedc
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/expected.json
@@ -0,0 +1,6 @@
+{
+  "key" : "value",
+  "object" : {
+    "test" : [ "dog", "cat", "bird" ]
+  }
+}
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/input.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/input.json
new file mode 100644
index 000000000..2bb482200
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/input.json
@@ -0,0 +1,3 @@
+{
+  "key":"value"
+}
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/test.fix b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/test.fix
new file mode 100644
index 000000000..f89d1fa5c
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/test.fix
@@ -0,0 +1 @@
+add_array("object.test[]", "dog", "cat", "bird")
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/test.flux b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/test.flux
new file mode 100644
index 000000000..7c3575fac
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithMultipleValues/test.flux
@@ -0,0 +1,8 @@
+FLUX_DIR + "input.json"
+|open-file
+|as-records
+|decode-json
+|fix(FLUX_DIR + "test.fix")
+|encode-json(prettyPrinting="true")
+|write(FLUX_DIR + "output-metafix.json")
+;
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/expected.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/expected.json
new file mode 100644
index 000000000..84542e0ef
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/expected.json
@@ -0,0 +1,6 @@
+{
+  "key" : "value",
+  "object" : {
+    "test" : [ "dog" ]
+  }
+}
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/input.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/input.json
new file mode 100644
index 000000000..2bb482200
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/input.json
@@ -0,0 +1,3 @@
+{
+  "key":"value"
+}
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/test.fix b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/test.fix
new file mode 100644
index 000000000..7e3807e3c
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/test.fix
@@ -0,0 +1 @@
+add_array("object.test[]", "dog")
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/test.flux b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/test.flux
new file mode 100644
index 000000000..7c3575fac
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithSingleValue/test.flux
@@ -0,0 +1,8 @@
+FLUX_DIR + "input.json"
+|open-file
+|as-records
+|decode-json
+|fix(FLUX_DIR + "test.fix")
+|encode-json(prettyPrinting="true")
+|write(FLUX_DIR + "output-metafix.json")
+;
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/expected.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/expected.json
new file mode 100644
index 000000000..9c6e32f3f
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/expected.json
@@ -0,0 +1,6 @@
+{
+  "key" : "value",
+  "object" : {
+    "test" : [ ]
+  }
+}
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/input.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/input.json
new file mode 100644
index 000000000..2bb482200
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/input.json
@@ -0,0 +1,3 @@
+{
+  "key":"value"
+}
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/test.fix b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/test.fix
new file mode 100644
index 000000000..d1c646335
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/test.fix
@@ -0,0 +1 @@
+add_array("object.test[]")
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/test.flux b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/test.flux
new file mode 100644
index 000000000..7c3575fac
--- /dev/null
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/add_arrayNestedSimpleWithoutValues/test.flux
@@ -0,0 +1,8 @@
+FLUX_DIR + "input.json"
+|open-file
+|as-records
+|decode-json
+|fix(FLUX_DIR + "test.fix")
+|encode-json(prettyPrinting="true")
+|write(FLUX_DIR + "output-metafix.json")
+;
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayIntoArrayOfObjectsWithAppend/expected.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayIntoArrayOfObjectsWithAppend/expected.json
index 1a843afd0..f4640bcdb 100644
--- a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayIntoArrayOfObjectsWithAppend/expected.json
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayIntoArrayOfObjectsWithAppend/expected.json
@@ -12,7 +12,5 @@
   }, {
     "name" : "Blacky",
     "type" : "bird"
-  }, {
-    "test" : [ "test", "test", "test" ]
   } ]
 }
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithMultipleValues/expected.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithMultipleValues/expected.json
index b2777dedc..d7a7e3b1f 100644
--- a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithMultipleValues/expected.json
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithMultipleValues/expected.json
@@ -1,6 +1,3 @@
 {
-  "key" : "value",
-  "object" : {
-    "test" : [ "dog", "cat", "bird" ]
-  }
+  "key" : "value"
 }
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithSingleValue/expected.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithSingleValue/expected.json
index 84542e0ef..d7a7e3b1f 100644
--- a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithSingleValue/expected.json
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithSingleValue/expected.json
@@ -1,6 +1,3 @@
 {
-  "key" : "value",
-  "object" : {
-    "test" : [ "dog" ]
-  }
+  "key" : "value"
 }
diff --git a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithoutValues/expected.json b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithoutValues/expected.json
index 9c6e32f3f..d7a7e3b1f 100644
--- a/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithoutValues/expected.json
+++ b/metafix/src/test/resources/org/metafacture/metafix/integration/record/fromJson/toJson/set_arrayNestedSimpleWithoutValues/expected.json
@@ -1,6 +1,3 @@
 {
-  "key" : "value",
-  "object" : {
-    "test" : [ ]
-  }
+  "key" : "value"
 }