diff --git a/TactilityC/Source/tt_init.cpp b/TactilityC/Source/tt_init.cpp
index 9c038e7c..afb75cd0 100644
--- a/TactilityC/Source/tt_init.cpp
+++ b/TactilityC/Source/tt_init.cpp
@@ -81,11 +81,24 @@ const struct esp_elfsym elf_symbols[] {
     ESP_ELFSYM_EXPORT(strncpy),
     ESP_ELFSYM_EXPORT(strcpy),
     ESP_ELFSYM_EXPORT(strcat),
+    ESP_ELFSYM_EXPORT(strchr),
     ESP_ELFSYM_EXPORT(strstr),
     ESP_ELFSYM_EXPORT(memset),
     ESP_ELFSYM_EXPORT(memcpy),
     // ctype
+    ESP_ELFSYM_EXPORT(isalnum),
+    ESP_ELFSYM_EXPORT(isalpha),
+    ESP_ELFSYM_EXPORT(iscntrl),
     ESP_ELFSYM_EXPORT(isdigit),
+    ESP_ELFSYM_EXPORT(isgraph),
+    ESP_ELFSYM_EXPORT(islower),
+    ESP_ELFSYM_EXPORT(isprint),
+    ESP_ELFSYM_EXPORT(ispunct),
+    ESP_ELFSYM_EXPORT(isspace),
+    ESP_ELFSYM_EXPORT(isupper),
+    ESP_ELFSYM_EXPORT(isxdigit),
+    ESP_ELFSYM_EXPORT(tolower),
+    ESP_ELFSYM_EXPORT(toupper),
     // ESP-IDF
     ESP_ELFSYM_EXPORT(esp_log_write),
     ESP_ELFSYM_EXPORT(esp_log_timestamp),