diff --git a/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapCompute.java b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapCompute.java
new file mode 100644
index 0000000..0d1e24d
--- /dev/null
+++ b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapCompute.java
@@ -0,0 +1,34 @@
+/*
+ * (C) Copyright 2016 PANTHEON.tech, s.r.o. and others.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package tech.pantheon.triemap;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+class TestConcurrentMapCompute {
+    private static final int COUNT = 50 * 1000;
+
+    @Test
+    void testConcurrentMapCompute() {
+        final var map = TrieMap.create();
+
+        for (int i = 0; i < COUNT; i++) {
+            assertEquals(i + " -> null", map.compute(i, (k, v) -> k + " -> " + v));
+            assertEquals(i + " -> " + i + " -> null", map.compute(i, (k, v) -> k + " -> " + v));
+        }
+    }
+}
diff --git a/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapComputeIfAbsent.java b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapComputeIfAbsent.java
new file mode 100644
index 0000000..11e9df1
--- /dev/null
+++ b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapComputeIfAbsent.java
@@ -0,0 +1,65 @@
+/*
+ * (C) Copyright 2016 PANTHEON.tech, s.r.o. and others.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package tech.pantheon.triemap;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertSame;
+
+class TestConcurrentMapComputeIfAbsent {
+    private static final int COUNT = 50 * 1000;
+
+    @Test
+    void testConcurrentMapComputeIfAbsentReturnsComputedValue() {
+        final var map = TrieMap.create();
+        for (int i = 0; i < COUNT; i++) {
+            assertEquals(Integer.toString(i), map.computeIfAbsent(i, Object::toString));
+        }
+    }
+
+    @Test
+    void testConcurrentMapComputeIfAbsentDoesNotComputeIfPresent() {
+        final var map = TrieMap.create();
+        for (int i = 0; i < COUNT; i++) {
+            map.put(i, Integer.toString(i));
+            assertEquals(Integer.toString(i), map.computeIfAbsent(i,
+                    (ignored) -> fail("Should not have called function")));
+        }
+    }
+
+    @Test
+    void testConflictingHash() {
+        final var k1 = new ZeroHashInt(1);
+        final var k2 = new ZeroHashInt(2);
+        final var k3 = new ZeroHashInt(3);
+        final var k3dup = new ZeroHashInt(3);
+        final var v1 = new ZeroHashInt(4);
+        final var v2 = new ZeroHashInt(5);
+        final var v3 = new ZeroHashInt(6);
+
+        final var map = TrieMap.<ZeroHashInt, ZeroHashInt>create();
+        // Pre-populate an LNode
+        assertSame(v1, map.computeIfAbsent(k1, k -> v1));
+        assertSame(v2, map.computeIfAbsent(k2, k -> v2));
+        assertSame(v3, map.computeIfAbsent(k3, k -> v3));
+
+        // Check with identical key
+        assertSame(v3, map.computeIfAbsent(k3, k -> v3));
+        // Check with equivalent key
+        assertSame(v3, map.computeIfAbsent(k3dup, k -> v3));
+    }
+}
\ No newline at end of file
diff --git a/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapComputeIfPresent.java b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapComputeIfPresent.java
new file mode 100644
index 0000000..0b3b971
--- /dev/null
+++ b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapComputeIfPresent.java
@@ -0,0 +1,80 @@
+/*
+ * (C) Copyright 2016 PANTHEON.tech, s.r.o. and others.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package tech.pantheon.triemap;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertSame;
+
+class TestConcurrentMapComputeIfPresent {
+    private static final int COUNT = 50 * 1000;
+
+    @Test
+    void testConcurrentMapComputeIfPresentDoesNotComputeIfAbsent() {
+        final var map = TrieMap.create();
+
+        for (int i = 0; i < COUNT; i++) {
+            assertNull(map.computeIfPresent(i, (k, v) -> fail("Should not have called function")));
+            assertFalse(map.containsKey(i));
+        }
+    }
+
+
+    @Test
+    void testConcurrentMapComputeIfPresent() {
+        final var map = TrieMap.create();
+
+        for (int i = 0; i < COUNT; i++) {
+            map.put(i, "42");
+            assertEquals(i + " -> 42", map.computeIfPresent(i, (k, v) -> k + " -> " + v));
+            assertEquals(i + " -> 42", map.get(i));
+        }
+    }
+
+    @Test
+    void testConcurrentMapComputeIfPresentRemovesValueIfComputesNull() {
+        final var map = TrieMap.create();
+
+        for (int i = 0; i < COUNT; i++) {
+            map.put(i, "42");
+            assertNull(map.computeIfPresent(i, (k, v) -> null));
+            assertFalse(map.containsKey(i));
+        }
+    }
+
+    @Test
+    void testConflictingHash() {
+        final var k1 = new ZeroHashInt(1);
+        final var k2 = new ZeroHashInt(2);
+        final var k3 = new ZeroHashInt(3);
+        final var k3dup = new ZeroHashInt(3);
+        final var v1 = new ZeroHashInt(4);
+        final var v2 = new ZeroHashInt(5);
+        final var v3 = new ZeroHashInt(6);
+
+        final var map = TrieMap.<ZeroHashInt, ZeroHashInt>create();
+        // Pre-populate an LNode
+        assertNull(map.putIfAbsent(k1, v1));
+        assertNull(map.putIfAbsent(k2, v2));
+        assertNull(map.putIfAbsent(k3, v3));
+
+        // Check with identical key
+        assertSame(v3, map.computeIfPresent(k3, (k, v) -> v3));
+        // Check with equivalent key
+        assertSame(v3, map.computeIfPresent(k3dup, (k, v) -> v3));
+    }
+}
diff --git a/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapMerge.java b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapMerge.java
new file mode 100644
index 0000000..0b7e200
--- /dev/null
+++ b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapMerge.java
@@ -0,0 +1,46 @@
+/*
+ * (C) Copyright 2016 PANTHEON.tech, s.r.o. and others.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package tech.pantheon.triemap;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
+
+import org.junit.jupiter.api.Test;
+
+class TestConcurrentMapMerge {
+    private static final int COUNT = 50 * 1000;
+
+    @Test
+    void testConcurrentMapMergeWhenValueAbsent() {
+        final var map = TrieMap.create();
+
+        for (int i = 0; i < COUNT; i++) {
+            final var newVal = Integer.toString(i + 10);
+            assertEquals(newVal, map.merge(i, newVal, (ov, nv) -> fail("Should not have been called")));
+        }
+    }
+
+    @Test
+    void testConcurrentMapMergeWhenValuePresent() {
+        final var map = TrieMap.create();
+
+        for (int i = 0; i < COUNT; i++) {
+            final var newVal = Integer.toString(i + 10);
+            map.put(i, newVal);
+            assertEquals(newVal + newVal, map.merge(i, newVal, (ov, nv) -> "" + ov + nv));
+        }
+    }
+}
diff --git a/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapPutIfAbsent.java b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapPutIfAbsent.java
index 99bb4ab..94be1db 100644
--- a/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapPutIfAbsent.java
+++ b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapPutIfAbsent.java
@@ -29,11 +29,22 @@ void testConcurrentMapPutIfAbsent() {
         final var map = TrieMap.create();
 
         for (int i = 0; i < COUNT; i++) {
-            assertNull(map.putIfAbsent(i, i));
-            assertEquals(Integer.valueOf(i), map.putIfAbsent(i, i));
+            assertNull(map.putIfAbsent(i, i + 10));
+            assertEquals(i + 10, map.get(i));
         }
     }
 
+    @Test
+    void testConcurrentMapPutIfAbsentSkipsIfPresent() {
+        final var map = TrieMap.create();
+
+        for (int i = 0; i < COUNT; i++) {
+            map.put(i, i + 10);
+            assertEquals(i + 10, map.putIfAbsent(i, i + 20));
+        }
+    }
+
+
     @Test
     void testConflictingHash() {
         final var k1 = new ZeroHashInt(1);
diff --git a/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapReplace.java b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapReplace.java
index ea7b62e..b728238 100644
--- a/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapReplace.java
+++ b/triemap/src/test/java/tech/pantheon/triemap/TestConcurrentMapReplace.java
@@ -33,7 +33,7 @@ void testConcurrentMapReplace() {
             assertNull(map.replace(i, "lol"));
             assertFalse(map.replace(i, i, "lol2"));
             assertNull(map.put(i, i));
-            assertEquals(Integer.valueOf(i), map.replace(i, "lol"));
+            assertEquals(i, map.replace(i, "lol"));
             assertFalse(map.replace(i, i, "lol2"));
             assertTrue(map.replace(i, "lol", i));
         }