diff --git a/services/track-changes/app/coffee/ConversionManager.coffee b/services/track-changes/app/coffee/ConversionManager.coffee
index fef745b220..5dca40a476 100644
--- a/services/track-changes/app/coffee/ConversionManager.coffee
+++ b/services/track-changes/app/coffee/ConversionManager.coffee
@@ -4,70 +4,70 @@ ConcatManager = require "./ConcatManager"
 module.exports = ConversionManager =
 	OPS_TO_LEAVE: 10
 
-	removeLatestCompressedUpdate: (doc_id, callback = (error) ->) ->
-		db.docHistory.update { doc_id: ObjectId(doc_id) }, { $pop: { docOps: 1 } }, callback
-
-	getLatestCompressedUpdate: (doc_id, callback = (error) ->) ->
-		db.docHistory.find { doc_id: ObjectId(doc_id) }, { docOps: { $slice: -1 } }, (error, history) ->
+	popLatestCompressedUpdate: (doc_id, callback = (error, update) ->) ->
+		db.docHistory.findAndModify
+			query: { doc_id: ObjectId(doc_id) }
+			fields: { docOps: { $slice: -1 } }
+			update: { $pop: { docOps: 1 } }
+		, (error, history = { docOps: [] }) ->
 			return callback(error) if error?
-			history = history[0] or { docOps: [] }
-			callback null, history.docOps.slice(-1)[0]
+			callback null, history.docOps[0]
 
 	insertCompressedUpdates: (doc_id, updates, callback = (error) ->) ->
 		db.docHistory.update { doc_id: ObjectId(doc_id) }, { $push: { docOps: { $each: updates } } }, { upsert: true }, callback
 
-	trimLastRawUpdate: (doc_id, tailVersion, callback = (error) ->) ->
-		db.docOps.update { doc_id: ObjectId(doc_id) }, { $pop: { docOps: -1 }, $set: { tailVersion: tailVersion + 1 } }, callback
-
-	getLastRawUpdateAndVersion: (doc_id, callback = (error, update, currentVersion, tailVersion) ->) ->
-		db.docOps.find { doc_id: ObjectId(doc_id) }, { version: true, tailVersion: true, docOps: { $slice: 1 } }, (error, docs) ->
+	popOldRawUpdates: (doc_id, callback = (error, updates) ->) ->
+		db.docOps.find { doc_id: ObjectId(doc_id) }, { version: true, tailVersion: true }, (error, docs) ->
 			return callback(error) if error?
 			return callback(new Error("doc not found")) if docs.length == 0
 			doc = docs[0]
-			callback null, doc.docOps[0], doc.version, doc.tailVersion or 0
-
-	convertOldestRawUpdate: (doc_id, callback = (error, converted) ->) ->
-		ConversionManager.getLastRawUpdateAndVersion doc_id, (error, rawUpdate, currentVersion, tailVersion) ->
-			return callback(error) if error?
-
+			currentVersion = doc.version
+			tailVersion = doc.tailVersion or 0
 			if currentVersion - tailVersion > ConversionManager.OPS_TO_LEAVE
-				rawUpdates = ConcatManager.normalizeUpdate(rawUpdate)
-				ConversionManager.getLatestCompressedUpdate doc_id, (error, lastCompressedUpdate) ->
+				db.docOps.findAndModify
+					query: { doc_id: ObjectId(doc_id), version: currentVersion }
+					update: {
+						$push: { docOps: { $each: [], $slice: - ConversionManager.OPS_TO_LEAVE } }
+						$set: tailVersion: currentVersion - ConversionManager.OPS_TO_LEAVE,
+						}
+					fields: { docOps: $slice: currentVersion - tailVersion - ConversionManager.OPS_TO_LEAVE }
+				, (error, doc) ->
 					return callback(error) if error?
-
-					removeAndModifyPreviousCompressedUpdate = (callback, compressedUpdates) ->
-						if lastCompressedUpdate?
-							compressedUpdates = [lastCompressedUpdate]
-							for rawUpdate in rawUpdates
-								lastCompressedUpdate = compressedUpdates.pop()
-								if lastCompressedUpdate?
-									compressedUpdates = compressedUpdates.concat ConcatManager.concatTwoUpdates lastCompressedUpdate, rawUpdate
-								else
-									compressedUpdates.push rawUpdate
-							ConversionManager.removeLatestCompressedUpdate doc_id, (error) ->
-								return callback(error) if error?
-								callback null, compressedUpdates
-						else
-							callback null, rawUpdates
+					if !doc?
+						# Version was modified since so try again
+						return ConversionManager.popOldRawUpdates doc_id, callback
+					else
+						return callback null, doc.docOps
 						
-					removeAndModifyPreviousCompressedUpdate (error, newCompressedUpdates) ->
-						return callback(error) if error?
-						ConversionManager.insertCompressedUpdates doc_id, newCompressedUpdates, (error) ->
-							return callback(error) if error?
-							ConversionManager.trimLastRawUpdate doc_id, tailVersion, (error) ->
-								return callback(error) if error?
-								console.log doc_id, "Pushed op", tailVersion
-								callback null, true
-
 			else
-				console.log doc_id, "Up to date"
-				callback null, false
+				callback null, []
 
-	convertAllOldRawUpdates: (doc_id, callback = (error) ->) ->
-		ConversionManager.convertOldestRawUpdate doc_id, (error, converted) ->
+	convertOldRawUpdates: (doc_id, callback = (error) ->) ->
+		ConversionManager.popOldRawUpdates doc_id, (error, rawUpdates) ->
 			return callback(error) if error?
-			if converted
-				# Keep going
-				ConversionManager.convertAllOldRawUpdates doc_id, callback
-			else
-				callback()
+
+			length = rawUpdates.length
+
+			normalizedRawUpdates = []
+			for rawUpdate in rawUpdates
+				normalizedRawUpdates = normalizedRawUpdates.concat ConcatManager.normalizeUpdate(rawUpdate)
+			rawUpdates = normalizedRawUpdates
+
+			ConversionManager.popLatestCompressedUpdate doc_id, (error, lastCompressedUpdate) ->
+				return callback(error) if error?
+
+				if !lastCompressedUpdate?
+					lastCompressedUpdate = rawUpdates.shift()
+
+				compressedUpdates = [lastCompressedUpdate]
+				for rawUpdate in rawUpdates
+					lastCompressedUpdate = compressedUpdates.pop()
+					if lastCompressedUpdate?
+						compressedUpdates = compressedUpdates.concat ConcatManager.concatTwoUpdates lastCompressedUpdate, rawUpdate
+					else
+						compressedUpdates.push rawUpdate
+				ConversionManager.insertCompressedUpdates doc_id, compressedUpdates, (error) ->
+					return callback(error) if error?
+					console.log doc_id, "Pushed doc ops", length
+					callback null, true
+
diff --git a/services/track-changes/compressHistory.coffee b/services/track-changes/compressHistory.coffee
index 95679a4dcd..c76988526f 100644
--- a/services/track-changes/compressHistory.coffee
+++ b/services/track-changes/compressHistory.coffee
@@ -9,7 +9,7 @@ db.docOps.find { }, { doc_id: true }, (error, docs) ->
 		do (doc) ->
 			jobs.push (callback) ->
 				doc_id = doc.doc_id.toString()
-				ConversionManager.convertAllOldRawUpdates doc_id, (error) ->
+				ConversionManager.convertOldRawUpdates doc_id, (error) ->
 					return callback(error) if error?
 					console.log doc_id, "DONE"
 					db.docHistory.find { doc_id: ObjectId(doc_id) }, (error, docs) ->
@@ -17,10 +17,10 @@ db.docOps.find { }, { doc_id: true }, (error, docs) ->
 						doc = docs[0]
 						if doc?
 							for update in doc.docOps
-								op = update.op[0]
-								if op.i?
+								op = update?.op[0]
+								if op?.i?
 									console.log doc_id, update.meta.start_ts, update.meta.end_ts, update.meta.user_id, "INSERT", op.p, op.i
-								else if op.d?
+								else if op?.d?
 									console.log doc_id, update.meta.start_ts, update.meta.end_ts, update.meta.user_id, "DELETE", op.p, op.d
 						else
 							console.log doc_id, "NO HISTORY"