diff --git a/pkgs/development/tools/icestorm/default.nix b/pkgs/development/tools/icestorm/default.nix
index c287e40d823..851acd17b7e 100644
--- a/pkgs/development/tools/icestorm/default.nix
+++ b/pkgs/development/tools/icestorm/default.nix
@@ -1,23 +1,26 @@
 { stdenv, fetchFromGitHub
 , pkgconfig, libftdi
 , python3, pypy3
+
+# PyPy yields large improvements in build time and runtime performance,
+# and IceStorm isn't intended to be used as a library other than by the
+# nextpnr build process (which is also sped up by using PyPy), so we
+# use it by default. See 18839e1 for more details.
+, usePyPy ? stdenv.isx86_64 /* pypy3 seems broken on i686 */
 }:
 
-let
-  pypyCompatible = stdenv.isx86_64; /* pypy3 seems broken on i686 */
-  pythonPkg      = if pypyCompatible then pypy3 else python3;
-  pythonInterp   = pythonPkg.interpreter;
-in
-
 stdenv.mkDerivation rec {
-  name = "icestorm-${version}";
-  version = "2019.04.16";
+  pname = "icestorm";
+  version = "2019.08.08";
+
+  pythonPkg = if usePyPy then pypy3 else python3;
+  pythonInterp = pythonPkg.interpreter;
 
   src = fetchFromGitHub {
     owner  = "cliffordwolf";
     repo   = "icestorm";
-    rev    = "d9ea2e15fccebbbce59409b0ae7a1481d78aab86";
-    sha256 = "1qa37p7hm7c2ga26xcvsd8xkqrp4hm0w6yh7cvz2q988yjzal5ky";
+    rev    = "2ccae0d3864fd7268118287a85963c0116745cff";
+    sha256 = "1vlk5k7x6c1bjp19niyl0shljj8il94q2brjmda1rwhqxz81g9s7";
   };
 
   nativeBuildInputs = [ pkgconfig ];