diff --git a/Makefile.am b/Makefile.am
index d85167b01..1a28c7fcc 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -442,7 +442,7 @@ i3_config_wizard_i3_config_wizard_SOURCES = \
 	i3-config-wizard/xcb.h
 
 i3_config_wizard_i3_config_wizard_DEPENDENCIES = \
-	$(config_parser_SOURCES)
+	$(top_builddir)/libi3.a
 
 test_inject_randr15_CPPFLAGS = \
 	$(AM_CPPFLAGS)
@@ -495,9 +495,9 @@ config_parser_SOURCES = \
 	parser/GENERATED_config_tokens.h \
 	parser/GENERATED_config_call.h
 
+BUILT_SOURCES = $(command_parser_SOURCES) $(config_parser_SOURCES)
+
 i3_SOURCES = \
-	$(command_parser_SOURCES) \
-	$(config_parser_SOURCES) \
 	include/all.h \
 	include/assignments.h \
 	include/atoms_NET_SUPPORTED.xmacro \
diff --git a/RELEASE-NOTES-4.18.1 b/RELEASE-NOTES-4.18.1
new file mode 100644
index 000000000..c05180f8d
--- /dev/null
+++ b/RELEASE-NOTES-4.18.1
@@ -0,0 +1,32 @@
+
+ ┌──────────────────────────────┐
+ │ Release notes for i3 v4.18.1 │
+ └──────────────────────────────┘
+
+This is i3 v4.18.1. This version is considered stable. All users of i3 are
+strongly encouraged to upgrade.
+
+This is a bugfix release for v4.18.
+
+ ┌────────────────────────────┐
+ │ Bugfixes                   │
+ └────────────────────────────┘
+
+  • Move parent nodes in scratchpad correctly
+  • i3bar: Call cont_child() more liberally
+  • Fix load_layout crash when floating node doesn't have CT_FLOATING_CON parent
+  • Fix SEGFAULT when i3bar receives invalid input
+  • Revert "floating_reposition: avoid extra tree_render"
+  • Call tree_render if floating move changes workspace
+  • Update EWMH properties on workspace move
+  • cmd_focus_sibling: Fix crash on workspace level
+
+ ┌────────────────────────────┐
+ │ Thanks!                    │
+ └────────────────────────────┘
+
+Thanks for testing, bugfixes, discussions and everything I forgot go out to:
+
+  Heman Gandhi, Orestis Floros
+
+-- Michael Stapelberg, 2020-04-22
diff --git a/RELEASE-NOTES-next b/RELEASE-NOTES-next
index e8a5dd861..c52a49ad9 100644
--- a/RELEASE-NOTES-next
+++ b/RELEASE-NOTES-next
@@ -32,3 +32,4 @@ strongly encouraged to upgrade.
   • do not focus floating windows changing workspace with ConfigureNotify
   • i3-dmenu-desktop: Support symlinks in search path
   • build: correctly provide auxiliary functions when needed
+  • build: fix issues with parallel build
diff --git a/travis/travis-base-386.Dockerfile b/travis/travis-base-386.Dockerfile
index 355c2588f..4649b8b46 100644
--- a/travis/travis-base-386.Dockerfile
+++ b/travis/travis-base-386.Dockerfile
@@ -18,7 +18,7 @@ RUN echo 'APT::Acquire::Retries "5";' > /etc/apt/apt.conf.d/80retry
 RUN linux32 apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
     dpkg-dev devscripts git equivs \
-    clang clang-format-6.0 \
+    build-essential clang clang-format-6.0 \
     lintian && \
     rm -rf /var/lib/apt/lists/*
 
diff --git a/travis/travis-base-ubuntu-386.Dockerfile b/travis/travis-base-ubuntu-386.Dockerfile
index d52df4b82..4aff0a8c6 100644
--- a/travis/travis-base-ubuntu-386.Dockerfile
+++ b/travis/travis-base-ubuntu-386.Dockerfile
@@ -18,7 +18,7 @@ RUN echo 'APT::Acquire::Retries "5";' > /etc/apt/apt.conf.d/80retry
 RUN linux32 apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
     dpkg-dev devscripts git equivs \
-    clang clang-format-6.0 \
+    build-essential clang clang-format-6.0 \
     lintian && \
     rm -rf /var/lib/apt/lists/*
 
diff --git a/travis/travis-base-ubuntu.Dockerfile b/travis/travis-base-ubuntu.Dockerfile
index d1057a390..dd2877270 100644
--- a/travis/travis-base-ubuntu.Dockerfile
+++ b/travis/travis-base-ubuntu.Dockerfile
@@ -19,7 +19,7 @@ RUN echo 'APT::Acquire::Retries "5";' > /etc/apt/apt.conf.d/80retry
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
     dpkg-dev devscripts git equivs \
-    clang clang-format-6.0 \
+    build-essential clang clang-format-6.0 \
     lintian && \
     rm -rf /var/lib/apt/lists/*
 
diff --git a/travis/travis-base.Dockerfile b/travis/travis-base.Dockerfile
index def7598df..b85c31835 100644
--- a/travis/travis-base.Dockerfile
+++ b/travis/travis-base.Dockerfile
@@ -17,7 +17,7 @@ RUN echo 'APT::Acquire::Retries "5";' > /etc/apt/apt.conf.d/80retry
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
     dpkg-dev devscripts git equivs \
-    clang clang-format-6.0 \
+    build-essential clang clang-format-6.0 \
     lintian \
     libmodule-install-perl libanyevent-perl libextutils-pkgconfig-perl xcb-proto cpanminus xvfb xserver-xephyr xauth libinline-perl libinline-c-perl libxml-simple-perl libmouse-perl libmousex-nativetraits-perl libextutils-depends-perl perl libtest-deep-perl libtest-exception-perl libxml-parser-perl libtest-simple-perl libtest-fatal-perl libdata-dump-perl libtest-differences-perl libxml-tokeparser-perl libipc-run-perl libxcb-xtest0-dev libx11-xcb-perl libjson-xs-perl x11-xserver-utils && \
     rm -rf /var/lib/apt/lists/*