diff --git a/copilot-core.cabal b/copilot-core.cabal
--- a/copilot-core.cabal
+++ b/copilot-core.cabal
@@ -1,16 +1,16 @@
 cabal-version:       >=1.10
 name:                copilot-core
-version:             0.2.4
+version:             2.1.1
 synopsis:            An intermediate representation for Copilot.
-description:         
-  Intermediate representation for Copilot. 
-  . 
+description:
+  Intermediate representation for Copilot.
+  .
   Copilot is a stream (i.e., infinite lists) domain-specific language (DSL) in
   Haskell that compiles into embedded C.  Copilot contains an interpreter,
   multiple back-end compilers, and other verification tools.  A tutorial, bug
   reports, and todos are available at
-  <https://github.com/niswegmann/copilot-discussion>.  
-  .  
+  <https://github.com/leepike/copilot-discussion>.
+  .
   Examples are available at
   <https://github.com/leepike/Copilot/tree/master/Examples>.
 
@@ -26,7 +26,7 @@
 
 source-repository head
     type:       git
-    location:   git://github.com/niswegmann/copilot-core.git
+    location:   git://github.com/leepike/copilot-core.git
 
 library
 
@@ -43,15 +43,15 @@
 
     --enable-library-profiling
 
-    -fpackage-trust    
+    -fpackage-trust
     -- Trusted packages
     -trust base
     -trust random
     -trust array
 
   build-depends:
-    containers >= 0.4 && < 1,
-    base >= 4.0 && < 5,
+    base >= 4.0 && <= 5.0,
+    containers >= 0.4,
     pretty >= 1.0,
     random > 1.0,
     pretty-ncols >= 0.1,
diff --git a/src/Copilot/Core/Interpret.hs b/src/Copilot/Core/Interpret.hs
--- a/src/Copilot/Core/Interpret.hs
+++ b/src/Copilot/Core/Interpret.hs
@@ -4,7 +4,7 @@
 
 -- | An interpreter for Copilot specifications.
 
-{-# LANGUAGE Safe #-}
+{-# LANGUAGE Trustworthy #-} -- Because of Containers
 
 module Copilot.Core.Interpret
   ( --ExtEnv (..)
diff --git a/src/Copilot/Core/Interpret/Eval.hs b/src/Copilot/Core/Interpret/Eval.hs
--- a/src/Copilot/Core/Interpret/Eval.hs
+++ b/src/Copilot/Core/Interpret/Eval.hs
@@ -4,7 +4,7 @@
 
 -- | A tagless interpreter for Copilot specifications.
 
-{-# LANGUAGE Safe #-}
+{-# LANGUAGE Trustworthy #-} -- Because of Data.Map (Containers)
 {-# LANGUAGE GADTs, BangPatterns, DeriveDataTypeable #-}
 
 module Copilot.Core.Interpret.Eval
diff --git a/src/Copilot/Core/Interpret/Render.hs b/src/Copilot/Core/Interpret/Render.hs
--- a/src/Copilot/Core/Interpret/Render.hs
+++ b/src/Copilot/Core/Interpret/Render.hs
@@ -4,7 +4,7 @@
 
 -- | An tagless interpreter for Copilot specifications.
 
-{-# LANGUAGE Safe #-}
+{-# LANGUAGE Trustworthy #-} -- Because of Data.Map (Containers)
 
 module Copilot.Core.Interpret.Render
   ( renderAsTable