try

Gemfile

@@ -5,7 +5,7 @@ gem 'volt', '0.9.5.pre4'
 # volt uses mongo as the default data store.
 gem 'volt-mongo', '~> 0.1.0'
 
-gem "parslet" , git: "https://github.com/salama/parslet.git"
+#gem "parslet" , git: "https://github.com/salama/parslet.git"
 gem "salama" , git: "https://github.com/salama/salama.git"
 gem "salama-reader" , git: "https://github.com/salama/salama-reader.git"
 gem "salama-arm" , git: "https://github.com/salama/salama-arm.git"

Gemfile.lock

@@ -1,9 +1,3 @@
-GIT
-  remote: https://github.com/salama/parslet.git
-  revision: beeb9b441a9ade1504f7f0e848d805e36a02c544
-  specs:
-    parslet (1.7.0)
-
 GIT
   remote: https://github.com/salama/salama-arm.git
   revision: 0bd5091e3f284ecf040e0086a41d2449cd5afb7a
@@ -35,6 +29,7 @@ GEM
   remote: https://rubygems.org/
   specs:
     bcrypt (3.1.10)
+    blankslate (3.1.3)
     bson (1.9.2)
     bson_ext (1.9.2)
       bson (~> 1.9.2)
@@ -86,6 +81,8 @@ GEM
       tilt (>= 1.4)
     opal-rspec (0.4.3)
       opal (>= 0.7.0, < 0.9)
+    parslet (1.7.0)
+      blankslate (>= 2.0, <= 4.0)
     poltergeist (1.5.1)
       capybara (~> 2.1)
       cliver (~> 0.3.1)
@@ -169,7 +166,6 @@ DEPENDENCIES
   csso-rails (~> 0.3.4)
   minitest
   opal-rspec (~> 0.4.2)
-  parslet!
   poltergeist (~> 1.5.0)
   rspec (~> 3.2.0)
   salama!