diff --git a/Gemfile b/Gemfile
index a7246a2..2018372 100644
--- a/Gemfile
+++ b/Gemfile
@@ -13,7 +13,7 @@ end
 
 group :runtime do
   gem "alf", "~> 0.11.1"
-  gem "epath", ">= 0"
+  gem "epath", "~> 0.1.0"
   gem "gnuplot", "~> 2.3.6"
   gem "json", ">= 0"
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index b4ceeab..7a75b1e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -7,7 +7,7 @@ GEM
       quickl (~> 0.4.2)
     backports (2.3.0)
     diff-lcs (1.1.3)
-    epath (0.0.1)
+    epath (0.1.0)
     gnuplot (2.3.6)
     json (1.6.5)
     myrrha (1.2.1)
@@ -28,7 +28,7 @@ PLATFORMS
 
 DEPENDENCIES
   alf (~> 0.11.1)
-  epath
+  epath (~> 0.1.0)
   gnuplot (~> 2.3.6)
   json
   rake (~> 0.9.2)
diff --git a/lib/viiite/bdb/immediate.rb b/lib/viiite/bdb/immediate.rb
index a3ea726..9044c13 100644
--- a/lib/viiite/bdb/immediate.rb
+++ b/lib/viiite/bdb/immediate.rb
@@ -19,7 +19,7 @@ def initialize(config)
       def each
         folder = config.benchmark_folder
         folder.glob(config.benchmark_pattern).each do |f|
-          yield(:name => f.relative_to(folder).without_extension.to_s, :file => f)
+          yield(:name => f.relative_to(folder).rm_ext.to_s, :file => f)
         end
       end
 
@@ -28,7 +28,7 @@ def cached?
       end
 
       def benchmark(name)
-        if (file = bench_file(config.benchmark_folder, name.to_s, @ext)).exist?
+        if (file = bench_file(config.benchmark_folder, name, @ext)).exist?
           return Viiite.bench(file)
         else
           raise NoSuchBenchmarkError, "No such benchmark #{name}"
diff --git a/lib/viiite/bdb/utils.rb b/lib/viiite/bdb/utils.rb
index 6d216b9..8927589 100644
--- a/lib/viiite/bdb/utils.rb
+++ b/lib/viiite/bdb/utils.rb
@@ -3,7 +3,7 @@ class BDB
     module Utils
 
       def bench_file(folder, name, ext)
-        folder.join(name).replace_extension(ext)
+        (folder/name).sub_ext(ext)
       end
 
       def folder
diff --git a/lib/viiite/command/commons.rb b/lib/viiite/command/commons.rb
index 984fcef..96ef894 100644
--- a/lib/viiite/command/commons.rb
+++ b/lib/viiite/command/commons.rb
@@ -5,10 +5,10 @@ module Commons
       def single_source(argv)
         raise Quickl::InvalidArgument if argv.size > 1
         if arg = argv.first
-          path = Path(arg.to_s)
+          path = Path(arg)
           if path.file?
             if path.extname == ".rb"
-              Viiite.bench(arg.to_s).run
+              Viiite.bench(arg).run
             else
               Alf::Reader.reader(path)
             end
diff --git a/lib/viiite/configuration.rb b/lib/viiite/configuration.rb
index ed9405c..0237b30 100644
--- a/lib/viiite/configuration.rb
+++ b/lib/viiite/configuration.rb
@@ -55,7 +55,7 @@ def cache_file_for(path)
       return nil unless path
       path = path.expand
       path = path.relative_to(benchmark_folder.expand)
-      (cache_folder/path).replace_extension(".rash")
+      (cache_folder/path).sub_ext(".rash")
     end
 
   end # class Configuration
diff --git a/spec/integration/test_command.rb b/spec/integration/test_command.rb
index ae19bff..9d62af7 100644
--- a/spec/integration/test_command.rb
+++ b/spec/integration/test_command.rb
@@ -6,8 +6,8 @@
 
     specify "#{input.base}: #{cmd}" do
       argv = Quickl.parse_commandline_args(cmd)[1..-1]
-      stdout = input.replace_extension('.stdout')
-      stderr = input.replace_extension('.stderr')
+      stdout = input.sub_ext('.stdout')
+      stderr = input.sub_ext('.stderr')
       stdout_expected = stdout.exist? ? stdout.read : ""
       stderr_expected = stderr.exist? ? stderr.read : ""
 
diff --git a/viiite.gemspec b/viiite.gemspec
index 82c8277..4167ab1 100644
--- a/viiite.gemspec
+++ b/viiite.gemspec
@@ -127,7 +127,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency("rspec", "~> 2.8.0")
   s.add_development_dependency("wlang", "~> 0.10.2")
   s.add_dependency("alf", "~> 0.11.1")
-  s.add_dependency("epath", ">= 0")
+  s.add_dependency("epath", "~> 0.1.0")
   s.add_dependency("gnuplot", "~> 2.3.6")
   s.add_dependency("json", ">= 0")
 
diff --git a/viiite.noespec b/viiite.noespec
index efb6cfb..8ebba07 100644
--- a/viiite.noespec
+++ b/viiite.noespec
@@ -32,7 +32,7 @@ variables:
     - {name: rspec,        version: "~> 2.8.0",  groups: [test, release]}
     - {name: wlang,        version: "~> 0.10.2", groups: [release      ]}
     - {name: alf,          version: "~> 0.11.1", groups: [runtime      ]}
-    - {name: epath,        version: ">= 0",      groups: [runtime      ]}
+    - {name: epath,        version: "~> 0.1.0",  groups: [runtime      ]}
     - {name: gnuplot,      version: "~> 2.3.6",  groups: [runtime      ]}
     - {name: json,         version: ">= 0",      groups: [runtime      ]}
   rake_tasks: