diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog for the [`clash-vhdl`](http://hackage.haskell.org/package/clash-vhdl) package
 
+## 0.6.12 *June 7th 2016*
+* Fixes bugs:
+  * Incorrect primitive specification for `snatToInteger` [#149](https://github.com/clash-lang/clash-compiler/issues/149)
+
 ## 0.6.11 *April 7th 2016*
 * Fixes bugs:
   * Incorrect primitives for `BitVector`s `quot#` and `rem#`
diff --git a/clash-vhdl.cabal b/clash-vhdl.cabal
--- a/clash-vhdl.cabal
+++ b/clash-vhdl.cabal
@@ -1,5 +1,5 @@
 Name:                 clash-vhdl
-Version:              0.6.11
+Version:              0.6.12
 Synopsis:             CAES Language for Synchronous Hardware - VHDL backend
 Description:
   CλaSH (pronounced ‘clash’) is a functional hardware description language that
@@ -97,15 +97,15 @@
                       TupleSections
                       ViewPatterns
 
-  Build-depends:      base                    >= 4.6.0.1 && < 5,
-                      clash-lib               >= 0.6.13,
-                      clash-prelude           >= 0.10.1,
-                      fgl                     >= 5.4.2.4,
-                      lens                    >= 3.9.2,
-                      mtl                     >= 2.1.2,
-                      text                    >= 0.11.3.1,
-                      unordered-containers    >= 0.2.3.3,
-                      wl-pprint-text          >= 1.1.0.0
+  Build-depends:      base                    >= 4.6.0.1  && < 5,
+                      clash-lib               >= 0.6.13   && < 0.7,
+                      clash-prelude           >= 0.10.1   && < 0.11,
+                      fgl                     >= 5.4.2.4  && < 5.6,
+                      lens                    >= 3.9.2    && < 4.15,
+                      mtl                     >= 2.1.2    && < 2.3,
+                      text                    >= 0.11.3.1 && < 1.3,
+                      unordered-containers    >= 0.2.3.3  && < 0.3,
+                      wl-pprint-text          >= 1.1.0.0  && < 1.2
 
   Exposed-modules:    CLaSH.Backend.VHDL
 
diff --git a/primitives/CLaSH.Promoted.Nat.json b/primitives/CLaSH.Promoted.Nat.json
--- a/primitives/CLaSH.Promoted.Nat.json
+++ b/primitives/CLaSH.Promoted.Nat.json
@@ -7,7 +7,7 @@
 , { "BlackBox" :
     { "name"      : "CLaSH.Promoted.Nat.snatToInteger"
     , "type"      : "snatToInteger :: SNat n -> Integer"
-    , "templateE" : "~ARG[0]"
+    , "templateE" : "~IF ~IW64 ~THEN to_signed(~ARG[0],64) ~ELSE to_signed(~ARG[0],32) ~FI"
     }
   }
 , { "BlackBox" :