diff --git a/_service b/_service
index 4125f8f..33a6b72 100644
--- a/_service
+++ b/_service
@@ -1,9 +1,9 @@
 <services>
   <service name="tar_scm" mode="disabled">
-    <param name="url">git://github.com/ocaml-community/cppo.git</param>
+    <param name="url">https://github.com/ocaml-community/cppo.git</param>
     <param name="scm">git</param>
-    <param name="versionformat">1.6.5</param>
-    <param name="revision">v1.6.5</param>
+    <param name="versionformat">1.6.6</param>
+    <param name="revision">v1.6.6</param>
     <param name="filename">ocaml-cppo</param>
   </service>
   <service name="recompress" mode="disabled">
diff --git a/ocaml-cppo-1.6.5.tar.xz b/ocaml-cppo-1.6.5.tar.xz
deleted file mode 100644
index 594804f..0000000
--- a/ocaml-cppo-1.6.5.tar.xz
+++ /dev/null
@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:880b31a6439423010297ab7e5f020c286633466d20602583ce38064496f03cce
-size 24400
diff --git a/ocaml-cppo-1.6.6.tar.xz b/ocaml-cppo-1.6.6.tar.xz
new file mode 100644
index 0000000..1864e85
--- /dev/null
+++ b/ocaml-cppo-1.6.6.tar.xz
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:121a5f0922cb465e0d802c42cc143768d63c37c921fc7b4c1699b3e3619725fb
+size 24848
diff --git a/ocaml-cppo.changes b/ocaml-cppo.changes
index bf9a65d..6a8557a 100644
--- a/ocaml-cppo.changes
+++ b/ocaml-cppo.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Mon Sep 23 16:35:39 UTC 2019 - ohering@suse.de
+
+- Update to 1.6.6
+  Fix build
+
 -------------------------------------------------------------------
 Tue Feb 19 03:21:22 UTC 2019 - andy@onthewings.net
 
diff --git a/ocaml-cppo.spec b/ocaml-cppo.spec
index 2a7d657..63ff068 100644
--- a/ocaml-cppo.spec
+++ b/ocaml-cppo.spec
@@ -18,12 +18,8 @@
 #
 
 
-# cppo may use opam-installer but opam requires cppo for its build.
-# So here we don't use opam-installer by default.
-# Build with "--with-opam" to use opam despite the circular dependency.
-%bcond_with opam
 Name:           ocaml-cppo
-Version:        1.6.5
+Version:        1.6.6
 Release:        0
 %{?ocaml_preserve_bytecode}
 Summary:        The C preprocessor written in OCaml
@@ -39,9 +35,6 @@ BuildRequires:  ocamlfind(easy-format)
 BuildRequires:  ocamlfind(ocamlbuild)
 BuildRequires:  ocamlfind(str)
 BuildRequires:  ocamlfind(unix)
-%if %{with opam}
-BuildRequires:  opam
-%endif
 
 %description
 Cppo is an equivalent of the C preprocessor targeted at the OCaml language and
@@ -66,30 +59,22 @@ The %{name}-devel package contains libraries and signature files for
 developing applications that use %{name}.
 
 %prep
-%setup -q
+%autosetup -p1
 
 %build
-dune build @install --profile release
+%ocaml_dune_setup
+%ocaml_dune_build
 
 %install
-%if %{with opam}
-  install -d %{buildroot}%{_libdir}/ocaml
-  dune install --prefix=%{buildroot}%{_prefix} --libdir=%{buildroot}%{_libdir}/ocaml
-  rm -r %{buildroot}%{_prefix}/doc
-%else
-  # By hand, not funny
-  cd _build/install/default
-  install -d %{buildroot}%{_libdir}/ocaml/cppo{,_ocamlbuild}
-  install -m0644 lib/cppo/* %{buildroot}%{_libdir}/ocaml/cppo/
-  install -m0644 lib/cppo_ocamlbuild/* %{buildroot}%{_libdir}/ocaml/cppo_ocamlbuild/
-  install -d %{buildroot}%{_bindir}
-  install -m0755 bin/cppo %{buildroot}%{_bindir}
-%endif
+%ocaml_dune_install
+
+%check
+%ocaml_dune_test
 
 %files
-%defattr(-,root,root)
 %{_bindir}/cppo
-%doc LICENSE.md README.md
+%license LICENSE.md
+%doc README.md
 %dir %{_libdir}/ocaml
 %dir %{_libdir}/ocaml/*
 %if 0%{?ocaml_native_compiler}
@@ -97,7 +82,6 @@ dune build @install --profile release
 %endif
 
 %files devel
-%defattr(-,root,root,-)
 %dir %{_libdir}/ocaml
 %dir %{_libdir}/ocaml/*
 %if 0%{?ocaml_native_compiler}