diff --git a/Makefile b/Makefile
index aa91ea531c5f0c1a60dddd855097151ae5c06042..e089b03f567d9b4b180f27a5fa5ff9c0ae866729 100644
--- a/Makefile
+++ b/Makefile
@@ -31,13 +31,15 @@ build-dep: build-dep/opam phony
 	@# that are incompatible with our build requirements.
 	@# To achieve this, we create a fake opam package that has our build-dependencies as
 	@# dependencies, but does not actually install anything.
-	@# Reinstalling is needed in case the pin already exists, but the builddep package changed.
-	@# Once we depend on opam 2, we can remove that last step.
+	@# Reinstalling is needed with opam 1 in case the pin already exists, but the builddep
+	@# package changed.
 	@BUILD_DEP_PACKAGE="$$(egrep "^name:" build-dep/opam | sed 's/^name: *"\(.*\)" */\1/')"; \
 	  echo "# Pinning build-dep package." && \
 	  opam pin add -k path $(OPAMFLAGS) "$$BUILD_DEP_PACKAGE".dev build-dep && \
-	  echo "# Reinstalling build-dep package." && \
-	  opam reinstall $(OPAMFLAGS) "$$BUILD_DEP_PACKAGE"
+	  ((! opam --version | grep "^1\." > /dev/null) || ( \
+	    echo "# Reinstalling build-dep package." && \
+	    opam reinstall $(OPAMFLAGS) "$$BUILD_DEP_PACKAGE" \
+	  ))
 
 # Some files that do *not* need to be forwarded to Makefile.coq
 Makefile: ;
diff --git a/ci b/ci
index 40b71102efe051c777a785035aebcbaa4c2ec19f..99c935d2007358fe4028560e96f9c136e608e696 160000
--- a/ci
+++ b/ci
@@ -1 +1 @@
-Subproject commit 40b71102efe051c777a785035aebcbaa4c2ec19f
+Subproject commit 99c935d2007358fe4028560e96f9c136e608e696