diff --git a/src/FTL.h b/src/FTL.h
index 64986a20..5eb91005 100644
--- a/src/FTL.h
+++ b/src/FTL.h
@@ -33,7 +33,6 @@
 #include <errno.h>
 #include <pthread.h>
 #include <sys/prctl.h>
-//#include <math.h>
 #include <pwd.h>
 // syslog
 #include <syslog.h>
diff --git a/src/database/sqlite3-ext.h b/src/database/sqlite3-ext.h
index 2636eb5d..56426571 100644
--- a/src/database/sqlite3-ext.h
+++ b/src/database/sqlite3-ext.h
@@ -8,5 +8,10 @@
 *  This file is copyright under the latest version of the EUPL.
 *  Please see LICENSE file for your rights under this license. */
 
+#ifndef SQLITE3_EXT_H
+#define SQLITE3_EXT_H
+
 // Initialization point for SQLite3 extensions
 extern int sqlite3_pihole_extensions_init(sqlite3 *db, const char **pzErrMsg, const struct sqlite3_api_routines *pApi);
+
+#endif // SQLITE3_EXT_H
\ No newline at end of file
diff --git a/src/ntp/server.c b/src/ntp/server.c
index ae9eed9c..7c89fd07 100644
--- a/src/ntp/server.c
+++ b/src/ntp/server.c
@@ -19,7 +19,6 @@
 #include <signal.h>
 // clock_gettime()
 #include <sys/time.h>
-//#include <sys/types.h>
 #include <sys/wait.h>
 // wait()
 #include <sys/socket.h>
diff --git a/src/tools/gravity-parseList.h b/src/tools/gravity-parseList.h
index e9e54ac4..b3e816b0 100644
--- a/src/tools/gravity-parseList.h
+++ b/src/tools/gravity-parseList.h
@@ -8,7 +8,12 @@
 *  This file is copyright under the latest version of the EUPL.
 *  Please see LICENSE file for your rights under this license. */
 
+#ifndef GRAVITY_PARSELIST_H
+#define GRAVITY_PARSELIST_H
+
 #include "FTL.h"
 
 int gravity_parseList(const char *infile, const char *outfile, const char *adlistID, const bool checkOnly, const bool antigravity);
 bool __attribute__((pure)) valid_domain(const char *domain, const size_t len, const bool fqdn_only);
+
+#endif // GRAVITY_PARSELIST_H
\ No newline at end of file
diff --git a/src/webserver/webserver.c b/src/webserver/webserver.c
index b3b05b94..cc4fe929 100644
--- a/src/webserver/webserver.c
+++ b/src/webserver/webserver.c
@@ -606,7 +606,7 @@ void FTL_rewrite_pattern(char *filename, unsigned long filename_buf_len)
 	filename_lp = append_to_path(filename, ".lp");
 	if(filename_lp == NULL)
 	{
-		//Failed to allocate memory for filename!");
+		// Failed to allocate memory for filename
 		return;
 	}