diff --git a/Logger.xcodeproj/project.pbxproj b/Logger.xcodeproj/project.pbxproj
index 69657b4..11a519e 100644
--- a/Logger.xcodeproj/project.pbxproj
+++ b/Logger.xcodeproj/project.pbxproj
@@ -20,6 +20,7 @@
 		2EBF4B592122B598008E4117 /* Logrotate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 2EBF4B562122B598008E4117 /* Logrotate.swift */; };
 		2ED077D721329CA30058EEFC /* LoggetTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 2ED077D621329CA30058EEFC /* LoggetTests.swift */; };
 		2ED077D92132A4820058EEFC /* AgregateLoggerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 2ED077D82132A4820058EEFC /* AgregateLoggerTests.swift */; };
+		2ED077DB2132B0320058EEFC /* FileSystem.swift in Sources */ = {isa = PBXBuildFile; fileRef = 2ED077DA2132B0320058EEFC /* FileSystem.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -62,6 +63,7 @@
 		2EBF4B562122B598008E4117 /* Logrotate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Logrotate.swift; sourceTree = "<group>"; };
 		2ED077D621329CA30058EEFC /* LoggetTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LoggetTests.swift; sourceTree = "<group>"; };
 		2ED077D82132A4820058EEFC /* AgregateLoggerTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AgregateLoggerTests.swift; sourceTree = "<group>"; };
+		2ED077DA2132B0320058EEFC /* FileSystem.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FileSystem.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -142,6 +144,7 @@
 				2EBF4B562122B598008E4117 /* Logrotate.swift */,
 				2EBF4B4F2122B06E008E4117 /* NSFileHandle+Swift.h */,
 				2EBF4B502122B06E008E4117 /* NSFileHandle+Swift.m */,
+				2ED077DA2132B0320058EEFC /* FileSystem.swift */,
 			);
 			path = DiskLogger;
 			sourceTree = "<group>";
@@ -252,6 +255,7 @@
 				2EBF4B3E2122AA34008E4117 /* Logger.swift in Sources */,
 				2EBF4B512122B06E008E4117 /* NSFileHandle+Swift.m in Sources */,
 				2EBF4B4B2122AF53008E4117 /* ConsoleLogger.swift in Sources */,
+				2ED077DB2132B0320058EEFC /* FileSystem.swift in Sources */,
 				2EBF4B4A2122AF53008E4117 /* AgregateLogger.swift in Sources */,
 				2EBF4B592122B598008E4117 /* Logrotate.swift in Sources */,
 				2EBF4B452122ACD6008E4117 /* LogStringConvertible.swift in Sources */,
diff --git a/Logger/Loggers/DiskLogger/DiskLogger.swift b/Logger/Loggers/DiskLogger/DiskLogger.swift
index d4cb80f..20e864e 100644
--- a/Logger/Loggers/DiskLogger/DiskLogger.swift
+++ b/Logger/Loggers/DiskLogger/DiskLogger.swift
@@ -97,7 +97,7 @@ public final class DiskLogger: Logger {
     }
     
     private func rotateLogFiles() throws {
-        let logrotate = Logrotate(fileURL: fileURL, rotations: rotations)
+        let logrotate = Logrotate(fileURL: fileURL, rotations: rotations, fileSystem: FileManager.default)
         try logrotate.rotate()
     }
 }
diff --git a/Logger/Loggers/DiskLogger/FileSystem.swift b/Logger/Loggers/DiskLogger/FileSystem.swift
new file mode 100644
index 0000000..d78c5f4
--- /dev/null
+++ b/Logger/Loggers/DiskLogger/FileSystem.swift
@@ -0,0 +1,38 @@
+//
+// MIT License
+//
+// Copyright (c) 2018 Wojciech Nagrodzki
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+
+import Foundation
+
+protocol FileSystem {
+    func itemExists(at URL: URL) -> Bool
+    func removeItem(at URL: URL) throws
+    func moveItem(at srcURL: URL, to dstURL: URL) throws
+}
+
+extension FileManager: FileSystem {
+    
+    func itemExists(at URL: URL) -> Bool {
+        return fileExists(atPath: URL.path)
+    }
+}
diff --git a/Logger/Loggers/DiskLogger/Logrotate.swift b/Logger/Loggers/DiskLogger/Logrotate.swift
index c377d2e..d2a97e4 100644
--- a/Logger/Loggers/DiskLogger/Logrotate.swift
+++ b/Logger/Loggers/DiskLogger/Logrotate.swift
@@ -29,16 +29,18 @@ final class Logrotate {
     
     private let fileURL: URL
     private let rotations: Int
+    private let fileSystem: FileSystem
     
     /// Initializes new Logrotate instance.
     ///
     /// - Parameters:
     ///   - fileURL: URL of the log file.
     ///   - rotations: Number of times log files are rotated before being removed.
-    init(fileURL: URL, rotations: Int) {
+    init(fileURL: URL, rotations: Int, fileSystem: FileSystem) {
         precondition(rotations > 0)
         self.fileURL = fileURL
         self.rotations = rotations
+        self.fileSystem = fileSystem
     }
     
     /// Rotates log files `rotations` number of times.
@@ -58,12 +60,12 @@ final class Logrotate {
         let toDelete = rotatedURLs.last!
         let toMove = zip(allURLs, rotatedURLs).reversed()
         
-        if FileManager.default.fileExists(atPath: toDelete.path) {
-            try FileManager.default.removeItem(at: toDelete)
+        if fileSystem.itemExists(at: toDelete) {
+            try fileSystem.removeItem(at: toDelete)
         }
         for (oldURL, newURL) in toMove {
-            guard FileManager.default.fileExists(atPath: oldURL.path) else { continue }
-            try FileManager.default.moveItem(at: oldURL, to: newURL)
+            guard fileSystem.itemExists(at: oldURL) else { continue }
+            try fileSystem.moveItem(at: oldURL, to: newURL)
         }
     }
 }