diff --git a/lib/datastore.js b/lib/datastore.js
index 139ec2d..f3fecaa 100644
--- a/lib/datastore.js
+++ b/lib/datastore.js
@@ -47,11 +47,6 @@ function Datastore (options) {
   this.executor = new Executor();
   if (this.inMemoryOnly) { this.executor.ready = true; }
 
-  // We keep internally the number of lines in the datafile
-  // This will be used when/if I implement autocompacting when the datafile grows too big
-  // For now it is not urgent as autocompaction happens upon every restart
-  this.datafileSize = 0;
-
   // Indexed by field name, dot notation can be used
   // _id is always indexed and since _ids are generated randomly the underlying
   // binary is always well-balanced
@@ -62,6 +57,14 @@ function Datastore (options) {
 }
 
 
+/**
+ * Load the database from the datafile, and trigger the execution of buffered commands if any
+ */
+Datastore.prototype.loadDatabase = function () {
+  this.executor.push({ this: this.persistence, fn: this.persistence.loadDatabase, arguments: arguments }, true);
+};
+
+
 /**
  * Get an array of all the data in the database
  */
@@ -235,13 +238,6 @@ Datastore.prototype.getCandidates = function (query) {
 };
 
 
-
-Datastore.prototype.loadDatabase = function () {
-  this.executor.push({ this: this.persistence, fn: this.persistence._loadDatabase, arguments: arguments }, true);
-};
-
-
-
 /**
  * Insert a new document
  * @param {Function} cb Optional callback, signature: err, insertedDoc
diff --git a/lib/persistence.js b/lib/persistence.js
index 149507d..3859f1c 100644
--- a/lib/persistence.js
+++ b/lib/persistence.js
@@ -1,5 +1,8 @@
 /**
  * Handle every persistence-related task
+ * The interface Datastore expects to be implemented is
+ * * Persistence.loadDatabase(callback) and callback has signature err
+ * * Persistence.persistNewState(newDocs, callback) where newDocs is an array of documents and callback has signature err
  */
 
 var fs = require('fs')
@@ -25,6 +28,11 @@ function Persistence (options) {
   if (this.filename && options.nodeWebkitAppName) {
     this.filename = Persistence.getNWAppFilename(options.nodeWebkitAppName, this.filename);
   }
+
+  // We keep internally the number of lines in the datafile
+  // This will be used when/if I implement autocompacting when the datafile grows too big
+  // For now it is not urgent as autocompaction happens upon every restart
+  this.datafileSize = 0;
 };
 
 
@@ -109,7 +117,7 @@ Persistence.prototype.persistNewState = function (newDocs, cb) {
   // In-memory only datastore
   if (self.inMemoryOnly) { return callback(null); }
 
-  self.db.datafileSize += newDocs.length;
+  self.datafileSize += newDocs.length;
 
   newDocs.forEach(function (doc) {
     toPersist += model.serialize(doc) + '\n';
@@ -166,13 +174,13 @@ Persistence.treatRawData = function (rawData) {
  *
  * @api private Use loadDatabase
  */
-Persistence.prototype._loadDatabase = function (cb) {
+Persistence.prototype.loadDatabase = function (cb) {
   var callback = cb || function () {}
     , self = this
     ;
 
   self.db.resetIndexes();
-  self.db.datafileSize = 0;
+  self.datafileSize = 0;
 
   // In-memory only datastore
   if (self.inMemoryOnly) { return callback(null); }
@@ -191,11 +199,11 @@ Persistence.prototype._loadDatabase = function (cb) {
               self.db.resetIndexes(treatedData);
             } catch (e) {
               self.db.resetIndexes();   // Rollback any index which didn't fail
-              self.db.datafileSize = 0;
+              self.datafileSize = 0;
               return cb(e);
             }
 
-            self.db.datafileSize = treatedData.length;
+            self.datafileSize = treatedData.length;
             self.db.persistence.persistCachedDatabase(cb);
           });
         });
diff --git a/test/db.test.js b/test/db.test.js
index c37bfb1..78f74d5 100644
--- a/test/db.test.js
+++ b/test/db.test.js
@@ -32,7 +32,7 @@ describe('Database', function () {
     , function (cb) {
         d.loadDatabase(function (err) {
           assert.isNull(err);
-          d.datafileSize.should.equal(0);
+          d.persistence.datafileSize.should.equal(0);
           d.getAllData().length.should.equal(0);
           return cb();
         });
@@ -171,16 +171,16 @@ describe('Database', function () {
     });
 
     it('datafileSize is incremented by 1 upon every insert', function (done) {
-      d.datafileSize.should.equal(0);
+      d.persistence.datafileSize.should.equal(0);
       d.getAllData().length.should.equal(0);
       d.insert({ a: 3 }, function () {
-        d.datafileSize.should.equal(1);
+        d.persistence.datafileSize.should.equal(1);
         d.getAllData().length.should.equal(1);
         d.insert({ a: 3 }, function () {
-          d.datafileSize.should.equal(2);
+          d.persistence.datafileSize.should.equal(2);
           d.getAllData().length.should.equal(2);
           d.insert({ a: 3 }, function () {
-            d.datafileSize.should.equal(3);
+            d.persistence.datafileSize.should.equal(3);
             d.getAllData().length.should.equal(3);
             done();
           });
@@ -890,15 +890,15 @@ describe('Database', function () {
       d.insert({ a: 2 }, function () {
         d.insert({ a: 3 }, function () {
           d.insert({ a: 5 }, function () {
-            d.datafileSize.should.equal(3);
+            d.persistence.datafileSize.should.equal(3);
             d.getAllData().length.should.equal(3);
 
             d.update({ a: 3 }, { $set: { a: 4 } }, {}, function () {
-              d.datafileSize.should.equal(4);
+              d.persistence.datafileSize.should.equal(4);
               d.getAllData().length.should.equal(3);
 
               d.update({ a: { $in: [2, 4] } }, { $set: { a: 5 } }, { multi: true }, function () {
-                d.datafileSize.should.equal(6);
+                d.persistence.datafileSize.should.equal(6);
                 d.getAllData().length.should.equal(3);
 
                 done();
@@ -1062,15 +1062,15 @@ describe('Database', function () {
       d.insert({ a: 2 }, function () {
         d.insert({ a: 3 }, function () {
           d.insert({ a: 5 }, function () {
-            d.datafileSize.should.equal(3);
+            d.persistence.datafileSize.should.equal(3);
             d.getAllData().length.should.equal(3);
 
             d.remove({ a: 3 }, {}, function () {
-              d.datafileSize.should.equal(4);
+              d.persistence.datafileSize.should.equal(4);
               d.getAllData().length.should.equal(2);
 
               d.remove({ a: { $in: [2, 5] } }, { multi: true }, function () {
-                d.datafileSize.should.equal(6);
+                d.persistence.datafileSize.should.equal(6);
                 d.getAllData().length.should.equal(0);
 
                 done();
@@ -1096,12 +1096,12 @@ describe('Database', function () {
           ;
 
         d.getAllData().length.should.equal(0);
-        d.datafileSize.should.equal(0);
+        d.persistence.datafileSize.should.equal(0);
 
         fs.writeFile(testDb, rawData, 'utf8', function () {
           d.loadDatabase(function () {
             d.getAllData().length.should.equal(3);
-            d.datafileSize.should.equal(3);
+            d.persistence.datafileSize.should.equal(3);
 
             assert.deepEqual(Object.keys(d.indexes), ['_id']);
 
@@ -1125,12 +1125,12 @@ describe('Database', function () {
           ;
 
         d.getAllData().length.should.equal(0);
-        d.datafileSize.should.equal(0);
+        d.persistence.datafileSize.should.equal(0);
 
         fs.writeFile(testDb, rawData, 'utf8', function () {
           d.loadDatabase(function () {
             d.getAllData().length.should.equal(2);
-            d.datafileSize.should.equal(2);
+            d.persistence.datafileSize.should.equal(2);
 
             assert.deepEqual(Object.keys(d.indexes), ['_id']);
 
@@ -1182,7 +1182,7 @@ describe('Database', function () {
           ;
 
         d.getAllData().length.should.equal(0);
-        d.datafileSize.should.equal(0);
+        d.persistence.datafileSize.should.equal(0);
 
         d.ensureIndex({ fieldName: 'z' });
         d.indexes.z.fieldName.should.equal('z');
@@ -1198,7 +1198,7 @@ describe('Database', function () {
               ;
 
             d.getAllData().length.should.equal(3);
-            d.datafileSize.should.equal(3);
+            d.persistence.datafileSize.should.equal(3);
 
             d.indexes.z.tree.getNumberOfKeys().should.equal(3);
             d.indexes.z.tree.search('1')[0].should.equal(doc1);
@@ -1218,7 +1218,7 @@ describe('Database', function () {
           ;
 
         d.getAllData().length.should.equal(0);
-        d.datafileSize.should.equal(0);
+        d.persistence.datafileSize.should.equal(0);
 
         d.ensureIndex({ fieldName: 'z' });
         d.ensureIndex({ fieldName: 'a' });
@@ -1233,7 +1233,7 @@ describe('Database', function () {
               ;
 
             d.getAllData().length.should.equal(3);
-            d.datafileSize.should.equal(3);
+            d.persistence.datafileSize.should.equal(3);
 
             d.indexes.z.tree.getNumberOfKeys().should.equal(3);
             d.indexes.z.tree.search('1')[0].should.equal(doc1);
@@ -1258,7 +1258,7 @@ describe('Database', function () {
           ;
 
         d.getAllData().length.should.equal(0);
-        d.datafileSize.should.equal(0);
+        d.persistence.datafileSize.should.equal(0);
 
         d.ensureIndex({ fieldName: 'z', unique: true });
         d.indexes.z.tree.getNumberOfKeys().should.equal(0);
@@ -1268,7 +1268,7 @@ describe('Database', function () {
             err.errorType.should.equal('uniqueViolated');
             err.key.should.equal("1");
             d.getAllData().length.should.equal(0);
-            d.datafileSize.should.equal(0);
+            d.persistence.datafileSize.should.equal(0);
             d.indexes.z.tree.getNumberOfKeys().should.equal(0);
 
             done();
diff --git a/test/persistence.test.js b/test/persistence.test.js
index 1f683f3..d4f440d 100644
--- a/test/persistence.test.js
+++ b/test/persistence.test.js
@@ -32,7 +32,7 @@ describe('Persistence', function () {
     , function (cb) {
         d.loadDatabase(function (err) {
           assert.isNull(err);
-          d.datafileSize.should.equal(0);
+          d.persistence.datafileSize.should.equal(0);
           d.getAllData().length.should.equal(0);
           return cb();
         });
@@ -162,12 +162,12 @@ describe('Persistence', function () {
       ;
 
     d.getAllData().length.should.equal(0);
-    d.datafileSize.should.equal(0);
+    d.persistence.datafileSize.should.equal(0);
 
     fs.writeFile(testDb, rawData, 'utf8', function () {
       d.loadDatabase(function () {
         d.getAllData().length.should.equal(3);
-        d.datafileSize.should.equal(3);
+        d.persistence.datafileSize.should.equal(3);
 
         d.find({}, function (err, docs) {
           docs.sort(function (a, b) { return a._id - b._id; });