diff --git a/icestorm.rb b/icestorm.rb
index 74f68da..e5a7298 100644
--- a/icestorm.rb
+++ b/icestorm.rb
@@ -7,7 +7,6 @@ class Icestorm < Formula
   depends_on "gnu-sed" => :build
   depends_on "libftdi"
   depends_on "python"
-  depends_on "icestorm"
 
   def install
 
diff --git a/nextpnr-ice40.rb b/nextpnr-ice40.rb
index 6ad9a0c..4cb0d80 100644
--- a/nextpnr-ice40.rb
+++ b/nextpnr-ice40.rb
@@ -7,14 +7,23 @@ class NextpnrIce40 < Formula
   depends_on "pkg-config" => :build
   depends_on "eigen" => :build
   depends_on "python@3.9"
-  depends_on "boost"
+  depends_on "boost@1.85"
   depends_on "boost-python3"
-  depends_on "qt5"
   depends_on "icestorm"
 
   def install
-    system "cmake", "-DARCH=ice40", ".", *std_cmake_args, "-DBoost_NO_BOOST_CMAKE=on", "-DBUILD_TESTS=OFF", "-DICEBOX_ROOT=#{HOMEBREW_PREFIX}/share/icebox"
-    system "make", "install"
+    boost = Formula["boost@1.85"]
+    icestorm = Formula["icestorm"]
+
+    ENV["CMAKE_PREFIX_PATH"] = boost.opt_prefix
+
+    mkdir "build" do
+      system "cmake", "..",
+             "-DARCH=ice40",
+             "-DICESTORM_INSTALL_PREFIX=#{icestorm.opt_prefix}",
+             *std_cmake_args
+      system "make", "install"
+    end
   end
 
 end