diff --git a/.gitmodules b/.gitmodules
index 7281ad5..0047079 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,3 @@
 [submodule "lib/libflint"]
 	path = lib/libflint
-	url = git@git.fputs.com:fputs/libflint
+	url = https://fputs.com/fputs/libflint
diff --git a/include/advent_utility.h b/include/advent_utility.h
index 88dbb89..e741d6d 100644
--- a/include/advent_utility.h
+++ b/include/advent_utility.h
@@ -7,10 +7,15 @@ struct Point {
 };
 
 struct Point new_Point(int, int);
-struct Point *new_Point_p(int, int);
-int same_Point(const struct Point*, const struct Point*);
-int same_Point_v(const void*, const void*);
 
-char *md5_str(const char*);
+struct Point *new_Point_p(int, int);
+
+int same_Point(const struct Point *, const struct Point *);
+
+int same_Point_v(const void *, const void *);
+
+char *md5_str(const char *);
+
+char *capture_system(const char *);
 
 #endif
diff --git a/src/2015/05.c b/src/2015/05.c
index c907452..79bea2a 100644
--- a/src/2015/05.c
+++ b/src/2015/05.c
@@ -1,10 +1,16 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#include "input.h"
+#include "advent_utility.h"
 
 void advent2015day05(void) {
-  char *input = get_input("input/2015/05");
-  printf("Solution for Day 05 of 2015 is not completed yet\n");
-  free(input);
+    /* Sometimes, grep really is the best tool */
+    char *p1 = capture_system(
+            "grep -E \"(.*[aeiou]){3}\" ./input/2015/05 | grep \"\\(.\\)\\1\" | egrep -v \"(ab|cd|pq|xy)\" | wc -l");
+    char *p2 = capture_system("grep \"\\(..\\).*\\1\" ./input/2015/05 | grep \"\\(.\\).\\1\" | wc -l");
+
+    printf("%s%s", p1, p2);
+
+    free(p1);
+    free(p2);
 }
diff --git a/src/advent_utility.c b/src/advent_utility.c
index 908bb64..82f1d3c 100644
--- a/src/advent_utility.c
+++ b/src/advent_utility.c
@@ -1,7 +1,14 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
+
+#ifdef __linux__
+
+#include <openssl/md5.h>
+
+#else
 #include <md5.h>
+#endif
 
 #include "advent_utility.h"
 
@@ -19,7 +26,7 @@ struct Point *new_Point_p(int x, int y) {
     return p;
 }
 
-int same_Point(const struct Point* a, const struct Point* b) {
+int same_Point(const struct Point *a, const struct Point *b) {
     if (a->x == b->x && a->y == b->y) {
         return 1;
     }
@@ -27,18 +34,38 @@ int same_Point(const struct Point* a, const struct Point* b) {
 }
 
 int same_Point_v(const void *a, const void *b) {
-    return same_Point((const struct Point *)a, (const struct Point *)b);
+    return same_Point((const struct Point *) a, (const struct Point *) b);
 }
 
-char *md5_str(const char* input) {
-   unsigned char digest[16];
-   struct MD5Context context;
-   MD5Init(&context);
-   MD5Update(&context, input, strlen(input));
-   MD5Final(digest, &context);
-   char *md5string = malloc(33);
-   for(int i = 0; i < 16; ++i) {
-       sprintf(&md5string[i*2], "%02x", (unsigned int)digest[i]);
-   }
-   return md5string;
+char *md5_str(const char *input) {
+    unsigned char digest[16];
+
+#ifdef __linux__
+    MD5_CTX context;
+    MD5_Init(&context);
+    MD5_Update(&context, input, strlen(input));
+    MD5_Final(digest, &context);
+#else
+    struct MD5Context context;
+    MD5Init(&context);
+    MD5Update(&context, input, strlen(input));
+    MD5Final(digest, &context);
+#endif
+
+    char *md5string = malloc(33);
+    for (int i = 0; i < 16; ++i) {
+        sprintf(&md5string[i * 2], "%02x", (unsigned int) digest[i]);
+    }
+    return md5string;
+}
+
+char *capture_system(const char *cmd) {
+    char *buf = malloc(256);
+    FILE *tmp = popen(cmd, "r");
+    if (tmp == NULL) {
+        printf("failed to open FILE *tmp\n");
+        exit(1);
+    }
+    fgets(buf, 256, tmp);
+    return buf;
 }