diff --git a/src/PlaylistDatabase.cxx b/src/PlaylistDatabase.cxx
index e785f9256..9ebaf1b41 100644
--- a/src/PlaylistDatabase.cxx
+++ b/src/PlaylistDatabase.cxx
@@ -25,6 +25,8 @@
 #include "util/StringStrip.hxx"
 #include "util/RuntimeError.hxx"
 
+#include <fmt/format.h>
+
 #include <cstring>
 
 #include <stdlib.h>
diff --git a/src/PlaylistSave.cxx b/src/PlaylistSave.cxx
index 64bffd7d0..c4848338b 100644
--- a/src/PlaylistSave.cxx
+++ b/src/PlaylistSave.cxx
@@ -32,6 +32,8 @@
 #include "io/BufferedOutputStream.hxx"
 #include "util/UriExtract.hxx"
 
+#include <fmt/format.h>
+
 static void
 playlist_print_path(BufferedOutputStream &os, const Path path)
 {
diff --git a/src/TagSave.cxx b/src/TagSave.cxx
index 749e19a56..6d758eddb 100644
--- a/src/TagSave.cxx
+++ b/src/TagSave.cxx
@@ -21,6 +21,8 @@
 #include "tag/Tag.hxx"
 #include "io/BufferedOutputStream.hxx"
 
+#include <fmt/format.h>
+
 #define SONG_TIME "Time: "
 
 void
diff --git a/src/db/plugins/simple/DatabaseSave.cxx b/src/db/plugins/simple/DatabaseSave.cxx
index 0862b2dc6..8caa5d039 100644
--- a/src/db/plugins/simple/DatabaseSave.cxx
+++ b/src/db/plugins/simple/DatabaseSave.cxx
@@ -29,6 +29,8 @@
 #include "util/RuntimeError.hxx"
 #include "Version.h"
 
+#include <fmt/format.h>
+
 #include <string.h>
 #include <stdlib.h>
 
diff --git a/src/db/plugins/simple/DirectorySave.cxx b/src/db/plugins/simple/DirectorySave.cxx
index 553ae4add..9bd59c889 100644
--- a/src/db/plugins/simple/DirectorySave.cxx
+++ b/src/db/plugins/simple/DirectorySave.cxx
@@ -31,6 +31,8 @@
 #include "util/NumberParser.hxx"
 #include "util/RuntimeError.hxx"
 
+#include <fmt/format.h>
+
 #include <string.h>
 
 #define DIRECTORY_DIR "directory: "
diff --git a/src/io/BufferedOutputStream.cxx b/src/io/BufferedOutputStream.cxx
index 9e7ae921f..82be92a01 100644
--- a/src/io/BufferedOutputStream.cxx
+++ b/src/io/BufferedOutputStream.cxx
@@ -30,6 +30,8 @@
 #include "BufferedOutputStream.hxx"
 #include "OutputStream.hxx"
 
+#include <fmt/format.h>
+
 #include <cstdarg>
 
 #include <string.h>
diff --git a/src/mixer/Volume.cxx b/src/mixer/Volume.cxx
index bfefb7327..97438ee43 100644
--- a/src/mixer/Volume.cxx
+++ b/src/mixer/Volume.cxx
@@ -26,6 +26,8 @@
 #include "io/BufferedOutputStream.hxx"
 #include "Log.hxx"
 
+#include <fmt/format.h>
+
 #include <cassert>
 
 #include <stdlib.h>
diff --git a/src/output/State.cxx b/src/output/State.cxx
index 28a9e2b64..60cd23707 100644
--- a/src/output/State.cxx
+++ b/src/output/State.cxx
@@ -29,6 +29,8 @@
 #include "io/BufferedOutputStream.hxx"
 #include "util/StringCompare.hxx"
 
+#include <fmt/format.h>
+
 #include <stdlib.h>
 
 #define AUDIO_DEVICE_STATE "audio_device_state:"
diff --git a/src/queue/PlaylistState.cxx b/src/queue/PlaylistState.cxx
index 317cb6c45..0c72f28a6 100644
--- a/src/queue/PlaylistState.cxx
+++ b/src/queue/PlaylistState.cxx
@@ -37,6 +37,8 @@
 #include "util/NumberParser.hxx"
 #include "Log.hxx"
 
+#include <fmt/format.h>
+
 #include <string.h>
 #include <stdlib.h>
 
diff --git a/src/queue/Save.cxx b/src/queue/Save.cxx
index 6020e950e..f2445a6c7 100644
--- a/src/queue/Save.cxx
+++ b/src/queue/Save.cxx
@@ -28,6 +28,8 @@
 #include "util/StringCompare.hxx"
 #include "Log.hxx"
 
+#include <fmt/format.h>
+
 #include <exception>
 
 #include <stdlib.h>