diff --git a/docs/string.md b/docs/string.md
index 0e4bd39..b7444a9 100644
--- a/docs/string.md
+++ b/docs/string.md
@@ -13,7 +13,7 @@ and subsequently the size of `substrings`.
 If no substrings are found, `substrings` will not be allocated and left set to `NULL`, `num_substrings` will be `0`, and
 the function will return `0`.
 
-Returns 0 if the function is successful, returns a non-zero value and prints to `stderr` if there is an error.
+Returns 0 if the function is successful. Returns a non-zero value if there is an error.
 
 ```c
 int find_substrings(const char* haystack, const char* needle, size_t *num_substrings, size_t **substrings);
@@ -34,7 +34,7 @@ free(subs);
 ### substr
 
 Extracts a substring at a specific index and length. This function returns a copy of the substring in a heap allocated
-buffer that the user is responsible for freeing. Returns `NULL` and prints to `stderr` if there is an error.
+buffer that the user is responsible for freeing. Returns `NULL` if there is an error.
 
 ```c
 const char* substr(const char* str, size_t idx, size_t len);
diff --git a/mkdocs.yml b/mkdocs.yml
index 9a013d5..7f3223a 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -12,5 +12,6 @@ nav:
     - 'Math': 'math.md'
     - 'Set': 'set.md'
     - 'Stack': 'stack.md'
+    - 'String': 'string.md'
     - 'Utility': 'utility.md'
     - 'Vector': 'vector.md'
diff --git a/src/string.c b/src/string.c
index 22bf91f..f277c5c 100644
--- a/src/string.c
+++ b/src/string.c
@@ -1,12 +1,10 @@
 #include <string.h>
 #include <stdlib.h>
-#include <stdio.h>
 
 #include "lfstring.h"
 
 int find_substrings(const char* haystack, const char* needle, size_t *num_substrings, size_t **substrings) {
     if (*substrings != NULL) {
-        fprintf(stderr, "substrings was not NULL in find_substring\n");
         return 1;
     }
 
@@ -29,7 +27,6 @@ int find_substrings(const char* haystack, const char* needle, size_t *num_substr
 
     *substrings = malloc(sizeof(size_t) * *num_substrings);
     if (*substrings == NULL) {
-        fprintf(stderr, "Memory allocation failed in find_substrings\n");
         return -1;
     }
 
@@ -46,13 +43,11 @@ int find_substrings(const char* haystack, const char* needle, size_t *num_substr
 const char* substr(const char* str, size_t idx, size_t len) {
    size_t sz_str = strlen(str);
    if (sz_str < len || idx + len > sz_str) {
-       fprintf(stderr, "Improper size arguments in substr\n");
        return NULL;
    }
 
    char *substr = malloc(sizeof(char) * len + 1);
    if (substr == NULL) {
-       fprintf(stderr, "Memory allocation error in substr\n");
        return NULL;
    }