diff --git a/java/src/com/android/inputmethod/latin/personalization/UserHistoryDictionaryBigramList.java b/java/src/com/android/inputmethod/latin/personalization/UserHistoryDictionaryBigramList.java
index f21db25..9f289e9 100644
--- a/java/src/com/android/inputmethod/latin/personalization/UserHistoryDictionaryBigramList.java
+++ b/java/src/com/android/inputmethod/latin/personalization/UserHistoryDictionaryBigramList.java
@@ -53,7 +53,7 @@
      * Called when loaded from the SQL DB.
      */
     public void addBigram(String word1, String word2, byte fcValue) {
-        if (UserHistoryPredictionDictionary.DBG_SAVE_RESTORE) {
+        if (DynamicPredictionDictionaryBase.DBG_SAVE_RESTORE) {
             Log.d(TAG, "--- add bigram: " + word1 + ", " + word2 + ", " + fcValue);
         }
         final HashMap<String, Byte> map;
@@ -73,7 +73,7 @@
      * Called when inserted to the SQL DB.
      */
     public void updateBigram(String word1, String word2, byte fcValue) {
-        if (UserHistoryPredictionDictionary.DBG_SAVE_RESTORE) {
+        if (DynamicPredictionDictionaryBase.DBG_SAVE_RESTORE) {
             Log.d(TAG, "--- update bigram: " + word1 + ", " + word2 + ", " + fcValue);
         }
         final HashMap<String, Byte> map;
diff --git a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
index a25cef5..c895a86 100644
--- a/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
+++ b/native/jni/com_android_inputmethod_latin_BinaryDictionary.cpp
@@ -53,6 +53,7 @@
         jlong dictOffset, jlong dictSize, jboolean isUpdatable) {
     PROF_OPEN;
     PROF_START(66);
+    // TODO: Move dictionary buffer handling to policyimpl.
     const jsize sourceDirUtf8Length = env->GetStringUTFLength(sourceDir);
     if (sourceDirUtf8Length <= 0) {
         AKLOGE("DICT: Can't get sourceDir string");
diff --git a/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h b/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
index e50baae..7f646e3 100644
--- a/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
+++ b/native/jni/src/suggest/core/dictionary/binary_dictionary_info.h
@@ -49,9 +49,7 @@
     }
 
     AK_FORCE_INLINE bool isDynamicallyUpdatable() const {
-        // TODO: Support dynamic dictionary formats.
-        const bool isUpdatableDictionaryFormat = false;
-        return mIsUpdatable && isUpdatableDictionaryFormat;
+        return mIsUpdatable;
     }
 
  private:
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.cpp b/native/jni/src/suggest/core/dictionary/dictionary.cpp
index af00e99..2ffd494 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.cpp
+++ b/native/jni/src/suggest/core/dictionary/dictionary.cpp
@@ -107,7 +107,7 @@
         AKLOGI("Warning: Dictionary::addUnigramWord() is called for non-updatable dictionary.");
         return;
     }
-    // TODO: Support dynamic update
+    mDictionaryStructureWithBufferPolicy->addUnigramWord(word, length, probability);
 }
 
 void Dictionary::addBigramWords(const int *const word0, const int length0, const int *const word1,
@@ -117,7 +117,8 @@
         AKLOGI("Warning: Dictionary::addBigramWords() is called for non-updatable dictionary.");
         return;
     }
-    // TODO: Support dynamic update
+    mDictionaryStructureWithBufferPolicy->addBigramWords(word0, length0, word1, length1,
+            probability);
 }
 
 void Dictionary::removeBigramWords(const int *const word0, const int length0,
@@ -127,7 +128,7 @@
         AKLOGI("Warning: Dictionary::removeBigramWords() is called for non-updatable dictionary.");
         return;
     }
-    // TODO: Support dynamic update
+    mDictionaryStructureWithBufferPolicy->removeBigramWords(word0, length0, word1, length1);
 }
 
 void Dictionary::logDictionaryInfo(JNIEnv *const env) const {
diff --git a/native/jni/src/suggest/core/dictionary/dictionary.h b/native/jni/src/suggest/core/dictionary/dictionary.h
index 17ce479..a54b62f 100644
--- a/native/jni/src/suggest/core/dictionary/dictionary.h
+++ b/native/jni/src/suggest/core/dictionary/dictionary.h
@@ -94,9 +94,9 @@
 
     const BinaryDictionaryInfo mBinaryDictionaryInfo;
     DictionaryStructureWithBufferPolicy *const mDictionaryStructureWithBufferPolicy;
-    const BigramDictionary *mBigramDictionary;
-    SuggestInterface *mGestureSuggest;
-    SuggestInterface *mTypingSuggest;
+    const BigramDictionary *const mBigramDictionary;
+    const SuggestInterface *const mGestureSuggest;
+    const SuggestInterface *const mTypingSuggest;
 
     void logDictionaryInfo(JNIEnv *const env) const;
 };
diff --git a/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h b/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
index 37daef9..5324115 100644
--- a/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
+++ b/native/jni/src/suggest/core/policy/dictionary_structure_with_buffer_policy.h
@@ -59,6 +59,18 @@
 
     virtual const DictionaryShortcutsStructurePolicy *getShortcutsStructurePolicy() const = 0;
 
+    // Returns whether the update was success or not.
+    virtual bool addUnigramWord(const int *const word, const int length,
+            const int probability) = 0;
+
+    // Returns whether the update was success or not.
+    virtual bool addBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1, const int probability) = 0;
+
+    // Returns whether the update was success or not.
+    virtual bool removeBigramWords(const int *const word0, const int length0,
+            const int *const word1, const int length1) = 0;
+
  protected:
     DictionaryStructureWithBufferPolicy() {}
 
diff --git a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp
index cca8010..311e94d 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp
@@ -231,4 +231,22 @@
     return nodeReader.getBigramsPos();
 }
 
+bool DynamicPatriciaTriePolicy::addUnigramWord(const int *const word, const int length,
+        const int probability) {
+    // TODO: Implement.
+    return false;
+}
+
+bool DynamicPatriciaTriePolicy::addBigramWords(const int *const word0, const int length0,
+        const int *const word1, const int length1, const int probability) {
+    // TODO: Implement.
+    return false;
+}
+
+bool DynamicPatriciaTriePolicy::removeBigramWords(const int *const word0, const int length0,
+        const int *const word1, const int length1) {
+    // TODO: Implement.
+    return false;
+}
+
 } // namespace latinime
diff --git a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.h
index ad8911c..4a5192c 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/dynamic_patricia_trie_policy.h
@@ -70,6 +70,14 @@
         return &mShortcutListPolicy;
     }
 
+    bool addUnigramWord(const int *const word, const int length, const int probability);
+
+    bool addBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1, const int probability);
+
+    bool removeBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1);
+
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(DynamicPatriciaTriePolicy);
     static const int MAX_CHILD_COUNT_TO_AVOID_INFINITE_LOOP;
diff --git a/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.h b/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.h
index 2e34480..0ed7945 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.h
+++ b/native/jni/src/suggest/policyimpl/dictionary/patricia_trie_policy.h
@@ -70,6 +70,23 @@
         return &mShortcutListPolicy;
     }
 
+    bool addUnigramWord(const int *const word, const int length, const int probability) {
+        // This dictionary format is not updatable.
+        return false;
+    }
+
+    bool addBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1, const int probability) {
+        // This dictionary format is not updatable.
+        return false;
+    }
+
+    bool removeBigramWords(const int *const word0, const int length0, const int *const word1,
+            const int length1) {
+        // This dictionary format is not updatable.
+        return false;
+    }
+
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(PatriciaTriePolicy);