diff --git a/Makefile b/Makefile
index e75bda6..3bad87b 100644
--- a/Makefile
+++ b/Makefile
@@ -1,16 +1,19 @@
 SOURCE := main.c opts.c directive.c file_utils.c error.c dictate.c remove_all.c
 SOURCE := $(addprefix source/, ${SOURCE})
 
-CFLAGS += -Wno-unused-label
-
 ifeq (${DEBUG}, 1)
+  CPPFLAGS += -DDEBUG
   CFLAGS += -O0 -ggdb -Wall -Wpedantic
   CFLAGS += -fsanitize=address
-  CPPFLAGS += -DDEBUG
+  ifeq (${CC}, clang)
+    CFLAGS += -Weverything -Wno-switch-default -std=c23 -Wno-pre-c23-compat
+  endif
 else
   CFLAGS += -O3 -flto=auto -fomit-frame-pointer
 endif
 
+CFLAGS += -Wno-unused-label
+
 OUT := vimdir
 
 ${OUT}: ${SOURCE}
diff --git a/source/directive.c b/source/directive.c
index dfb4f81..599ec49 100644
--- a/source/directive.c
+++ b/source/directive.c
@@ -33,7 +33,7 @@ int path_cmp(const char * a, const char * b) {
     if (*b == '/' && *a != '\0') { return  1; }
 
   end:
-    return *(unsigned char *)a - *(unsigned char *)b;
+    return *(const unsigned char *)a - *(const unsigned char *)b;
 }
 
 static
@@ -136,11 +136,11 @@ int init_directive_c(const char * const folder) {
 }
 
 int deinit_directive_c(void) {
-    for (int i = 0; i < entries.n; i++) {
+    for (size_t i = 0; i < entries.n; i++) {
         free(kv_A(entries, i).name);
     }
 
-    for (int i = 0; i < move_data.n; i++) {
+    for (size_t i = 0; i < move_data.n; i++) {
         move_data_t move = kv_A(move_data, i);
         free(move.orig_name);
         free(move.curt_name);
@@ -156,10 +156,10 @@ int deinit_directive_c(void) {
 }
 
 int make_directive_file(FILE * f) {
-    for (int i = 0; i < entries.n; i++) {
+    for (size_t i = 0; i < entries.n; i++) {
         entry_t * entry = &kv_A(entries, i);
         // ID
-        fprintf(f, "%03d",
+        fprintf(f, "%03ld",
             i
         );
         // Permissions
@@ -354,7 +354,7 @@ int execute_directive_file(FILE * f) {
     }
 
     // Deletion
-    for (int i = 0; i < entries.n; i++) {
+    for (size_t i = 0; i < entries.n; i++) {
         entry_t * entry = &kv_A(entries, i);
         if (!entry->is_mentioned) {
             CHECK(mydelete(entry->name));
@@ -362,7 +362,7 @@ int execute_directive_file(FILE * f) {
     }
 
     // Swap (move)
-    for (int i = 0; i < move_data.n; i++) {
+    for (size_t i = 0; i < move_data.n; i++) {
         move_data_t move = kv_A(move_data, i);
         // NOTE: we could be overwritting here;
         //        thats the behaviour the user would expect
@@ -386,7 +386,7 @@ int execute_directive_file(FILE * f) {
      * Therefor, files waiting to be swapped (possessing a temporary name) are restored back
      *  (if possible, if we run into another error, theres not much to do).
      */
-    for (int i = 0; i < move_data.n; i++) {
+    for (size_t i = 0; i < move_data.n; i++) {
         move_data_t move = kv_A(move_data, i);
         if (!access(move.orig_name, F_OK)) {
             mymove(move.curt_name, move.orig_name);
diff --git a/source/error.h b/source/error.h
index d66c879..b032e99 100644
--- a/source/error.h
+++ b/source/error.h
@@ -21,10 +21,11 @@ enum {
 extern void errorn(int n, ...);
 extern void notice(const char * fmt, ...);
 
-#define CHECK_OPEN(f, n, E) \
-    if (!f) { \
-        errorn(E_FILE_ACCESS, n); \
-        E; \
-    }
+#define CHECK_OPEN(f, n, E) do { \
+        if (!f) { \
+            errorn(E_FILE_ACCESS, n); \
+            E; \
+        } \
+    } while (0)
 
 #endif
diff --git a/source/file_utils.c b/source/file_utils.c
index f1f2d82..c472f2c 100644
--- a/source/file_utils.c
+++ b/source/file_utils.c
@@ -4,6 +4,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
+#include <sys/types.h>
 #include <unistd.h>
 #include <pwd.h>
 #include <grp.h>
@@ -70,7 +71,7 @@ int init_file_utils(bool is_dry_run, const char * custom_rm_) {
     return 0;
 }
 
-int deinit_file_utis() {
+int deinit_file_utis(void) {
     mytouch  = NULL;
     mydelete = NULL;
     mychmod  = NULL;
diff --git a/source/file_utils.h b/source/file_utils.h
index d77f142..f183b0e 100644
--- a/source/file_utils.h
+++ b/source/file_utils.h
@@ -3,9 +3,10 @@
 
 #include <stdbool.h>
 #include <sys/stat.h>
+#include <sys/types.h>
 
 extern int init_file_utils(bool is_dry_run, const char * custom_rm_);
-extern int deinit_file_utis();
+extern int deinit_file_utis(void);
 
 extern char * trim_trailing_slashes(char * path);
 
diff --git a/source/main.c b/source/main.c
index 54b713b..1672a41 100644
--- a/source/main.c
+++ b/source/main.c
@@ -4,6 +4,7 @@
 #include <string.h>
 #include <stdarg.h>
 #include <unistd.h>
+#include "global.h"
 #include "error.h"
 #include "opts.h"
 #include "directive.h"
@@ -17,6 +18,7 @@ bool is_recursive   = false;
 bool do_permissions = false;
 bool do_owner       = false;
 
+static
 int get_tmpfile_name(char * name_buffer) {
   #if DEBUG == 1
     strcpy(name_buffer, "vimdir_test_file.vimdir");
@@ -32,6 +34,7 @@ int get_tmpfile_name(char * name_buffer) {
   #endif
 }
 
+static
 int edit(const char * filename) {
     size_t cmd_len = strlen(editor) + sizeof(' ') + strlen(filename) + 1;
     char cmd[cmd_len];
@@ -67,7 +70,7 @@ signed main(int argc, char * * argv) {
     folder = trim_trailing_slashes(folder);
 
   create:
-    FILE * tmpfile;
+    FILE * tmpfile = NULL;
     char tmpfile_name[32];
 
     CHECK(get_tmpfile_name(tmpfile_name));