diff --git a/epitar/Makefile b/epitar/Makefile
index 52c4801..10068ef 100644
--- a/epitar/Makefile
+++ b/epitar/Makefile
@@ -22,7 +22,7 @@ $(TARGET): $(OBJS)
 	@echo $(OBJS)
 
 all: $(OBJS)
-	$(CC) -o $@ $^ $(LDFLAGS) $(LDLIBS)
+	$(CC) -o $(TARGET) $^ $(LDFLAGS) $(LDLIBS)
 
 debug: CFLAGS += $(DBG_CFLAGS)
 debug: LDFLAGS += $(DBG_LDFLAGS)
diff --git a/epitar/src/main.c b/epitar/src/main.c
index 1e12eb4..92171d5 100644
--- a/epitar/src/main.c
+++ b/epitar/src/main.c
@@ -3,6 +3,57 @@
 #include "utils/config.h"
 #include "utils/errors.h"
 
+static int handle_err_code(enum error_code err, struct config *config)
+{
+    int ret_code = 0;
+    switch (err)
+    {
+    case SUCCESS:
+        ret_code = 0;
+        break;
+
+    case BAD_CHECKSUM:
+        puts("epitar: bad checksum");
+        ret_code = 2;
+        break;
+
+    case NOT_IMPLEMENTED:
+        puts("epitar: Function not implemented");
+        ret_code = 2;
+        break;
+
+    case FILE_NOT_FOUND:
+        if (config->mode == ARCHIVE)
+        {
+            // Rest of code should have printed the first part of the line
+            printf(" to tarball %s\n", config->archive_file);
+            ret_code = 3;
+            break;
+        }
+        __attribute__((fallthrough));
+
+    case EMPTY_ARCHIVE:
+        if (config->mode == ARCHIVE)
+        {
+            puts("epitar: cowardly refusing to create an empty archive");
+            ret_code = 1;
+        }
+        else
+        {
+            printf("epitar: error extracting tarball %s\n",
+                   config->archive_file);
+            ret_code = 3;
+        }
+        break;
+
+    default:
+        printf("epitar: error extracting tarball %s\n", config->archive_file);
+        ret_code = 3;
+        break;
+    }
+    return ret_code;
+}
+
 int main(int argc, char **argv)
 {
     // Handle args
@@ -32,48 +83,7 @@ int main(int argc, char **argv)
         err = archive(config.archive_file, config.input_files, config.verbose);
     }
 
-    int ret_code = 0;
-    switch (err)
-    {
-    case SUCCESS:
-        ret_code = 0;
-        break;
-
-        // case UNKNOWN_ERROR:
-        //     printf("epitar: error extracting tarball %s\n",
-        //     config.archive_file); ret_code = 3; break;
-
-    case BAD_CHECKSUM:
-        puts("epitar: bad checksum");
-        ret_code = 2;
-        break;
-
-    case NOT_IMPLEMENTED:
-        puts("epitar: Function not implemented");
-        ret_code = 2;
-        break;
-
-    case FILE_NOT_FOUND:
-        if (config.mode == ARCHIVE)
-        {
-            // Rest of code should have printed the first part of the line
-            printf(" to tarball %s\n", config.archive_file);
-            ret_code = 3;
-            break;
-        }
-        __attribute__((fallthrough));
-
-    case EMPTY_ARCHIVE:
-        puts("epitar: cowardly refusing to create an empty archive");
-        ret_code = 1;
-        break;
-
-    default:
-        printf("epitar: error extracting tarball %s\n", config.archive_file);
-        ret_code = 3;
-        break;
-    }
-
+    int ret_code = handle_err_code(err, &config);
     destroy_config(&config);
     return ret_code;
 }
diff --git a/epitar/src/tar/archive.c b/epitar/src/tar/archive.c
index 00ae94d..ed0b247 100644
--- a/epitar/src/tar/archive.c
+++ b/epitar/src/tar/archive.c
@@ -100,7 +100,7 @@ static enum error_code archivefile(FILE *archive, char *file_path, bool verbose)
     FILE *file = fopen(file_path, "r");
     if (file == NULL)
     {
-        printf("Unable to add file %s", file_path);
+        printf("unable to add file %s", file_path);
         return FILE_NOT_FOUND;
     }
 
@@ -162,7 +162,7 @@ static enum error_code archivedir(FILE *archive, char *dir_path, bool verbose)
         if (isdir == FILE_NOT_FOUND)
         {
             // Does not exists
-            printf("Unable to add file %s", dir_path);
+            printf("unable to add file %s", dir_path);
             err = FILE_NOT_FOUND;
         }
         else if (isdir == SUCCESS)
@@ -204,7 +204,7 @@ enum error_code archive(char *archive_name, char **files, bool verbose)
         if (isdir == FILE_NOT_FOUND)
         {
             // Does not exists
-            printf("Unable to add file %s", *current_file);
+            printf("unable to add file %s", *current_file);
             err = FILE_NOT_FOUND;
         }
         else if (isdir == SUCCESS)
diff --git a/epitar/src/tar/archive.h b/epitar/src/tar/archive.h
index 546f4ff..f9dd21f 100644
--- a/epitar/src/tar/archive.h
+++ b/epitar/src/tar/archive.h
@@ -1,10 +1,10 @@
 #ifndef ARCHIVE_H
 #define ARCHIVE_H
 
-#include "../utils/errors.h"
-
 #include <stdbool.h>
 
+#include "../utils/errors.h"
+
 /* @brief Archives the listed `files` into `archive_name`
  * @return 0 on success, the corresponding error code otherwise
  */
diff --git a/epitar/src/tar/extract.c b/epitar/src/tar/extract.c
index 77ffcbd..28f2677 100644
--- a/epitar/src/tar/extract.c
+++ b/epitar/src/tar/extract.c
@@ -5,6 +5,7 @@
 #include <string.h>
 
 #include "../utils/filesystem.h"
+#include "tar.h"
 
 /**
  *
@@ -49,9 +50,14 @@ static enum error_code extract_ustar(FILE *stream, struct ustar_header *header)
 static enum error_code extract_unixtar(FILE *stream,
                                        struct unixtar_header *header)
 {
-    (void)stream;
-    (void)header;
-    return NOT_IMPLEMENTED;
+    struct file_stats stats = { .name = header->name,
+                                .length = strtol(header->size, NULL, 8),
+                                .content_stream = stream,
+                                .mode = header->mode,
+                                .uid = header->uid,
+                                .gid = header->gid,
+                                .mtime = header->mtime };
+    return create_file(&stats);
 }
 
 /**
@@ -130,6 +136,12 @@ enum error_code extract(char *archive_name, bool verbose)
             got_empty_block = false;
         }
 
+        if (!check_checksum(&header))
+        {
+            fclose(stream);
+            return BAD_CHECKSUM;
+        }
+
         // Extract file
         enum error_code err = extract_file(stream, &header, verbose);
         if (err != SUCCESS)
diff --git a/epitar/src/utils/config.c b/epitar/src/utils/config.c
index 45e4dfb..a46a5a7 100644
--- a/epitar/src/utils/config.c
+++ b/epitar/src/utils/config.c
@@ -81,7 +81,7 @@ enum arg_error_code args_handler(int argc, char **argv, struct config *config)
 
     // Parse option flags
     int opt;
-    while ((opt = getopt(argc, argv, "cxvh")) != -1)
+    while ((opt = getopt(argc, argv, ":cvxh")) != -1)
     {
         int err = handle_opt(opt, config);
         if (err == ARG_HELP)
diff --git a/epitar/src/utils/filesystem.c b/epitar/src/utils/filesystem.c
index 6f3f237..9116034 100644
--- a/epitar/src/utils/filesystem.c
+++ b/epitar/src/utils/filesystem.c
@@ -180,7 +180,7 @@ char *listdirectory(char *path)
     return de->d_name;
 }
 
-void freedirectory()
+void freedirectory(void)
 {
     if (current_dir != NULL)
     {
diff --git a/epitar/src/utils/filesystem.h b/epitar/src/utils/filesystem.h
index b504c4d..160c800 100644
--- a/epitar/src/utils/filesystem.h
+++ b/epitar/src/utils/filesystem.h
@@ -59,6 +59,6 @@ char *listdirectory(char *path);
  * related allocated memory
  * @warn Use this function if you only partially listed a directory previously.
  */
-void freedirectory();
+void freedirectory(void);
 
 #endif // FILESYSTEM_H
diff --git a/epitar/src/utils/misc.c b/epitar/src/utils/misc.c
deleted file mode 100644
index 0271150..0000000
--- a/epitar/src/utils/misc.c
+++ /dev/null
@@ -1,3 +0,0 @@
-#include "utils.h"
-
-#include <stdio.h>
diff --git a/epitar/src/utils/misc.h b/epitar/src/utils/misc.h
deleted file mode 100644
index 3d20ecc..0000000
--- a/epitar/src/utils/misc.h
+++ /dev/null
@@ -1,6 +0,0 @@
-#ifndef MISC_H
-#define MISC_H
-
-void print_str_array(const char **input_files);
-
-#endif /* MISC_H */
diff --git a/epitar/tests/functional/run.sh b/epitar/tests/functional/run.sh
index 37d5497..70b07f4 100644
--- a/epitar/tests/functional/run.sh
+++ b/epitar/tests/functional/run.sh
@@ -282,7 +282,23 @@ echo -e "\n$BBlue=== Help and Invalid Arguments ===$Color_Off"
 test_help "Help flag"
 test_invalid_args "No arguments" ""
 test_invalid_args "Invalid flag" "-z"
-test_invalid_args "Missing archive" "-c"
+test_invalid_args "Invalid flagS" "-zbk"
+test_invalid_args "Invalid position" "test.tar -h"
+test_invalid_args "Invalid flags and position" "test.tar -z"
+test_invalid_args "Invalid flags and position mix" "test.tar -zhx"
+test_invalid_args "Invalid position" "test.tar -z"
+test_invalid_args "Invalid flag mix" "-zh"
+test_invalid_args "Invalid flag mix 2" "-hnh"
+test_invalid_args "Invalid flag mix 3" "-cnc"
+test_invalid_args "Invalid flag mix 3" "-hhhz"
+test_invalid_args "Invalid flag mix 3" "-hnc"
+test_invalid_args "Invalid flag mix 3" "-cch"
+test_invalid_args "Invalid flag mix 3" "-cnc"
+test_invalid_args "Valid flags multiple" "-cc"
+test_invalid_args "Incompatible flag" "-cx"
+test_invalid_args "Missing op flag" "-v"
+test_invalid_args "Missing archive (c)" "-c"
+test_invalid_args "Missing archive (x)" "-x"
 test_invalid_args "Extract with files" "-x archive.tar file.txt"
 
 echo -e "\n$BBlue=== Edge Cases ===$Color_Off"