diff --git a/engine/src/soundldr/flac.cc b/engine/src/soundldr/flac.cc
index f812160..42a35c5 100644
--- a/engine/src/soundldr/flac.cc
+++ b/engine/src/soundldr/flac.cc
@@ -1,3 +1,4 @@
+#include <cstring>
 #include <fishbone/foundation.h>
 
 struct fishbone::Sound::Impl {
diff --git a/engine/src/soundldr/mp3.cc b/engine/src/soundldr/mp3.cc
index 057330f..c6fc083 100644
--- a/engine/src/soundldr/mp3.cc
+++ b/engine/src/soundldr/mp3.cc
@@ -1,3 +1,4 @@
+#include <cstring>
 #include <fishbone/foundation.h>
 
 struct fishbone::Sound::Impl {
diff --git a/engine/src/soundldr/vorbis.cc b/engine/src/soundldr/vorbis.cc
index 56d3047..574ebc6 100644
--- a/engine/src/soundldr/vorbis.cc
+++ b/engine/src/soundldr/vorbis.cc
@@ -1,3 +1,4 @@
+#include <cstring>
 #include <fishbone/foundation.h>
 
 struct fishbone::Sound::Impl {
diff --git a/engine/src/soundldr/wav.cc b/engine/src/soundldr/wav.cc
index 5703b68..62b9abc 100644
--- a/engine/src/soundldr/wav.cc
+++ b/engine/src/soundldr/wav.cc
@@ -1,3 +1,4 @@
+#include <cstring>
 #include <fishbone/foundation.h>
 
 struct fishbone::Sound::Impl {
diff --git a/engine/src/soundldr/xmp.cc b/engine/src/soundldr/xmp.cc
index f2f0a77..7b4e845 100644
--- a/engine/src/soundldr/xmp.cc
+++ b/engine/src/soundldr/xmp.cc
@@ -1,3 +1,4 @@
+#include <cstring>
 #include <fishbone/foundation.h>
 
 struct fishbone::Sound::Impl {