diff --git a/blankie/murl.cpp b/blankie/murl.cpp
index 2dddfc0..2c69865 100644
--- a/blankie/murl.cpp
+++ b/blankie/murl.cpp
@@ -189,20 +189,20 @@ static inline void hexencode(char c, char out[2]) {
     char nibble1 = (c >> 4) & 0xF;
     char nibble2 = c & 0xF;
 
-    auto hexencode = [](char nibble) -> char {
-        return nibble < 10
+    auto hexencode = [](char nibble) {
+        return static_cast<char>(nibble < 10
             ? '0' + nibble
-            : 'A' + nibble - 10;
+            : 'A' + nibble - 10);
     };
     out[0] = hexencode(nibble1);
     out[1] = hexencode(nibble2);
 }
 
 static inline char hexdecode(char nibble1, char nibble2) {
-    auto hexdecode = [](char nibble) -> char {
-        if (nibble >= '0' && nibble <= '9') return nibble - '0';
-        if (nibble >= 'A' && nibble <= 'F') return nibble - 'A' + 10;
-        if (nibble >= 'a' && nibble <= 'f') return nibble - 'a' + 10;
+    auto hexdecode = [](char nibble) {
+        if (nibble >= '0' && nibble <= '9') return static_cast<char>(nibble - '0');
+        if (nibble >= 'A' && nibble <= 'F') return static_cast<char>(nibble - 'A' + 10);
+        if (nibble >= 'a' && nibble <= 'f') return static_cast<char>(nibble - 'a' + 10);
         throw std::invalid_argument("Invalid percent-encoded nibble received");
     };