diff --git a/src/main/java/com/lbry/database/PrefixDB.java b/src/main/java/com/lbry/database/PrefixDB.java
index a7edf41..4e12933 100644
--- a/src/main/java/com/lbry/database/PrefixDB.java
+++ b/src/main/java/com/lbry/database/PrefixDB.java
@@ -1,5 +1,6 @@
 package com.lbry.database;
 
+import com.lbry.database.keys.UndoKey;
 import com.lbry.database.revert.RevertibleDelete;
 import com.lbry.database.revert.RevertibleOperation;
 import com.lbry.database.revert.RevertibleOperationStack;
@@ -7,16 +8,10 @@ import com.lbry.database.revert.RevertiblePut;
 import com.lbry.database.rows.*;
 
 import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
 import java.util.*;
 
-import org.rocksdb.ColumnFamilyDescriptor;
-import org.rocksdb.ColumnFamilyHandle;
-import org.rocksdb.DBOptions;
-import org.rocksdb.Options;
-import org.rocksdb.ReadOptions;
-import org.rocksdb.RocksDB;
-import org.rocksdb.RocksDBException;
-import org.rocksdb.RocksIterator;
+import org.rocksdb.*;
 
 /**
  * Class for a revertible RocksDB database: A RocksDB database where each set of applied changes can be undone.
@@ -81,6 +76,14 @@ public class PrefixDB{
     }
 
     public PrefixDB(String path,int maxOpenFiles,String secondaryPath,int maxUndoDepth) throws RocksDBException{
+        this(path,maxOpenFiles,secondaryPath,maxUndoDepth,null);
+    }
+
+    public PrefixDB(String path,int maxOpenFiles,String secondaryPath,int maxUndoDepth,Set<Byte> unsafePrefixes) throws RocksDBException{
+        this(path,maxOpenFiles,secondaryPath,maxUndoDepth,unsafePrefixes,true);
+    }
+
+    public PrefixDB(String path,int maxOpenFiles,String secondaryPath,int maxUndoDepth,Set<Byte> unsafePrefixes,boolean enforceIntegrity) throws RocksDBException{
         List<ColumnFamilyDescriptor> columnFamilyDescriptors = new ArrayList<>();
         columnFamilyDescriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY));
         for(Prefix prefix : Prefix.values()){
@@ -100,8 +103,6 @@ public class PrefixDB{
 
         this.database = RocksDB.open(new DBOptions(options),path,columnFamilyDescriptors,this.columnFamilyHandles);
 
-        Set<Byte> unsafePrefixes = new HashSet<>();//TODO
-        boolean enforceIntegrity = false;//TODO
         this.operationStack = new RevertibleOperationStack((byte[] key) -> {
             try{
                 return Optional.of(this.get(key));
@@ -161,28 +162,98 @@ public class PrefixDB{
     /**
      * Write staged changes to the database without keeping undo information. Changes written cannot be undone.
      */
-    public void unsafeCommit(){
+    public void unsafeCommit() throws RocksDBException{
         this.applyStash();
+        WriteOptions writeOptions = new WriteOptions().setSync(true);
         try{
-            //TODO
+            if(this.operationStack.length()!=0){
+                return;
+            }
+            WriteBatch batch = new WriteBatch();
+            for(RevertibleOperation stagedChange : this.operationStack.interate()){
+                ColumnFamilyHandle columnFamily = this.getColumnFamilyByPrefix(Prefix.getByValue(stagedChange.getKey()[0]));
+                if(!stagedChange.isDelete()){
+                    batch.put(columnFamily,stagedChange.getKey(),stagedChange.getValue());
+                }else{
+                    batch.delete(columnFamily,stagedChange.getKey());
+                }
+                this.database.write(writeOptions,batch);
+            }
+        }finally{
+            writeOptions.close();
+            this.operationStack.clear();
+        }
+    }
+
+    public void commit(int height,byte[] blockHash) throws RocksDBException{
+        this.applyStash();
+        byte[] undoOperations = this.operationStack.getUndoOperations();
+        List<byte[]> deleteUndos = new ArrayList<>();
+        if(height>this.maxUndoDepth){
+            byte[] upperBound = ByteBuffer.allocate(1+8).order(ByteOrder.BIG_ENDIAN).put(Prefix.UNDO.getValue()).putLong(height-this.maxUndoDepth).array();
+            RocksIterator iterator = this.database.newIterator(new ReadOptions().setIterateUpperBound(new Slice(upperBound)));
+            iterator.seek(ByteBuffer.allocate(1+8).order(ByteOrder.BIG_ENDIAN).put(Prefix.UNDO.getValue()).array());
+            while(iterator.isValid()){
+                deleteUndos.add(iterator.key());
+                iterator.next();
+            }
+        }
+        try{
+            ColumnFamilyHandle undoColumnFamily = this.getColumnFamilyByPrefix(Prefix.UNDO);
+            WriteOptions writeOptions = new WriteOptions().setSync(true);
+            try{
+                WriteBatch batch = new WriteBatch();
+                for(RevertibleOperation stagedChange : this.operationStack.interate()){
+                    ColumnFamilyHandle columnFamily = this.getColumnFamilyByPrefix(Prefix.getByValue(stagedChange.getKey()[0]));
+                    if(!stagedChange.isDelete()){
+                        batch.put(columnFamily,stagedChange.getKey(),stagedChange.getValue());
+                    }else{
+                        batch.delete(columnFamily,stagedChange.getKey());
+                    }
+
+                }
+                for(byte[] undoToDelete : deleteUndos){
+                    batch.delete(undoColumnFamily,undoToDelete);
+                }
+                UndoKey undoKey = new UndoKey();
+                undoKey.height = height;
+                undoKey.block_hash = blockHash;
+                byte[] undoKeyBytes = this.undo.packKey(undoKey);
+                batch.put(undoColumnFamily,undoKeyBytes,undoOperations);
+                this.database.write(writeOptions,batch);
+            }finally{
+                writeOptions.close();
+                this.operationStack.clear();
+            }
         }finally{
             this.operationStack.clear();
         }
     }
 
-    public void commit(){
-        this.applyStash();
+    public void rollback(int height,byte[] blockHash) throws RocksDBException{
+        UndoKey undoKey = new UndoKey();
+        undoKey.height = height;
+        undoKey.block_hash = blockHash;
+        byte[] undoKeyBytes = this.undo.packKey(undoKey);
+        ColumnFamilyHandle undoColumnFamily = this.getColumnFamilyByPrefix(Prefix.UNDO);
+        byte[] undoInfo = this.database.get(undoColumnFamily,undoKeyBytes);
+        this.operationStack.applyPackedUndoOperations(undoInfo);
+        this.operationStack.validateAndApplyStashedOperations();
+        WriteOptions writeOptions = new WriteOptions().setSync(true);
         try{
-            //TODO
-        }finally{
-            this.operationStack.clear();
-        }
-    }
-
-    public void rollback(int height,byte[] blockHash){
-        try{
-            //TODO
+            WriteBatch batch = new WriteBatch();
+            for(RevertibleOperation stagedChange : this.operationStack.interate()){
+                ColumnFamilyHandle columnFamily = this.getColumnFamilyByPrefix(Prefix.getByValue(stagedChange.getKey()[0]));
+                if(!stagedChange.isDelete()){
+                    batch.put(columnFamily,stagedChange.getKey(),stagedChange.getValue());
+                }else{
+                    batch.delete(columnFamily,stagedChange.getKey());
+                }
+                this.database.write(writeOptions,batch);
+            }
+            // batch.delete(undoKey)
         }finally{
+            writeOptions.close();
             this.operationStack.clear();
         }
     }
diff --git a/src/main/java/com/lbry/database/revert/RevertibleOperationStack.java b/src/main/java/com/lbry/database/revert/RevertibleOperationStack.java
index a1e1a16..e7bcf8e 100644
--- a/src/main/java/com/lbry/database/revert/RevertibleOperationStack.java
+++ b/src/main/java/com/lbry/database/revert/RevertibleOperationStack.java
@@ -6,6 +6,7 @@ import java.nio.ByteBuffer;
 import java.util.*;
 import java.util.function.Function;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 public class RevertibleOperationStack{
 
@@ -419,6 +420,14 @@ public class RevertibleOperationStack{
         this.stashedLastOperationForKey.clear();
     }
 
+    public int length(){
+        return this.items.values().stream().mapToInt(x -> x.length).sum();
+    }
+
+    public Iterable<RevertibleOperation> interate(){
+        return this.items.values().stream().flatMap(Stream::of).collect(Collectors.toList());
+    }
+
     /**
      * Get the serialized bytes to undo all of the changes made by the pending ops
      */