diff --git a/.vscode/settings.json b/.vscode/settings.json
index 4f728b2..8d4c0e6 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,3 +1,6 @@
 {
-  "rubocop.mode": "onlyRunGlobally"
+  "rubocop.mode": "onlyRunGlobally",
+  "files.associations": {
+    "picohttpparser.h": "c"
+  }
 }
diff --git a/src/main.c b/src/main.c
index 0e40a36..b65498b 100755
--- a/src/main.c
+++ b/src/main.c
@@ -12,6 +12,8 @@
 #include <mruby/class.h>
 #include <mruby/string.h>
 
+#include <picohttpparser.h>
+
 #define DEFAULT_PORT 7000
 #define DEFAULT_BACKLOG 128