diff --git a/Makefile b/Makefile
index 62a4850d8..d26cf8d99 100644
--- a/Makefile
+++ b/Makefile
@@ -28,7 +28,7 @@ makefiles = \
   doc/manual/local.mk \
   tests/local.mk
 
-GLOBAL_CXXFLAGS += -std=c++14 -g -Wall
+GLOBAL_CXXFLAGS += -std=c++14 -g -Wall -include config.h
 
 -include Makefile.config
 
diff --git a/src/libexpr/json-to-value.cc b/src/libexpr/json-to-value.cc
index f671802bc..c189cdef3 100644
--- a/src/libexpr/json-to-value.cc
+++ b/src/libexpr/json-to-value.cc
@@ -1,4 +1,3 @@
-#include "config.h"
 #include "json-to-value.hh"
 
 #include <cstring>
diff --git a/src/libexpr/symbol-table.hh b/src/libexpr/symbol-table.hh
index 2fdf82021..c2ee49dd3 100644
--- a/src/libexpr/symbol-table.hh
+++ b/src/libexpr/symbol-table.hh
@@ -1,7 +1,5 @@
 #pragma once
 
-#include "config.h"
-
 #include <map>
 #include <unordered_set>
 
diff --git a/src/libexpr/value.hh b/src/libexpr/value.hh
index 271e6a1b2..81f918d48 100644
--- a/src/libexpr/value.hh
+++ b/src/libexpr/value.hh
@@ -1,6 +1,5 @@
 #pragma once
 
-#include "config.h"
 #include "symbol-table.hh"
 
 #if HAVE_BOEHMGC
diff --git a/src/libmain/shared.cc b/src/libmain/shared.cc
index 52cb23128..56aa3db00 100644
--- a/src/libmain/shared.cc
+++ b/src/libmain/shared.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #include "common-args.hh"
 #include "globals.hh"
 #include "shared.hh"
diff --git a/src/libmain/stack.cc b/src/libmain/stack.cc
index abf59dc4b..57b6a197c 100644
--- a/src/libmain/stack.cc
+++ b/src/libmain/stack.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #include "types.hh"
 
 #include <cstring>
diff --git a/src/libstore/build.cc b/src/libstore/build.cc
index 5d6fff4e3..1aee150fd 100644
--- a/src/libstore/build.cc
+++ b/src/libstore/build.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #include "references.hh"
 #include "pathlocks.hh"
 #include "globals.hh"
diff --git a/src/libstore/globals.cc b/src/libstore/globals.cc
index 00b468892..90f83a5bb 100644
--- a/src/libstore/globals.cc
+++ b/src/libstore/globals.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #include "globals.hh"
 #include "util.hh"
 #include "archive.hh"
diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 612efde7b..4c161cfb3 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -1,4 +1,3 @@
-#include "config.h"
 #include "local-store.hh"
 #include "globals.hh"
 #include "archive.hh"
diff --git a/src/libstore/optimise-store.cc b/src/libstore/optimise-store.cc
index b71c7e905..cf234e35d 100644
--- a/src/libstore/optimise-store.cc
+++ b/src/libstore/optimise-store.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #include "util.hh"
 #include "local-store.hh"
 #include "globals.hh"
diff --git a/src/libstore/s3-binary-cache-store.cc b/src/libstore/s3-binary-cache-store.cc
index ccb71f1ee..cc1b33104 100644
--- a/src/libstore/s3-binary-cache-store.cc
+++ b/src/libstore/s3-binary-cache-store.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #if ENABLE_S3
 #if __linux__
 
diff --git a/src/libutil/archive.cc b/src/libutil/archive.cc
index fbba7f853..e0e6f5dfd 100644
--- a/src/libutil/archive.cc
+++ b/src/libutil/archive.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #include <cerrno>
 #include <algorithm>
 #include <vector>
diff --git a/src/libutil/hash.cc b/src/libutil/hash.cc
index aa50fceb9..f447c80c5 100644
--- a/src/libutil/hash.cc
+++ b/src/libutil/hash.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #include <iostream>
 #include <cstring>
 
diff --git a/src/libutil/types.hh b/src/libutil/types.hh
index b9a93d27d..97d79af9b 100644
--- a/src/libutil/types.hh
+++ b/src/libutil/types.hh
@@ -1,6 +1,5 @@
 #pragma once
 
-#include "config.h"
 
 #include "ref.hh"
 
diff --git a/src/libutil/util.cc b/src/libutil/util.cc
index 6c4c5c969..336599368 100644
--- a/src/libutil/util.cc
+++ b/src/libutil/util.cc
@@ -1,5 +1,3 @@
-#include "config.h"
-
 #include "util.hh"
 #include "affinity.hh"
 #include "sync.hh"