diff --git a/inst/include/tidysq/ProtoSq.h b/inst/include/tidysq/ProtoSq.h
index 8ea818f..84ae672 100644
--- a/inst/include/tidysq/ProtoSq.h
+++ b/inst/include/tidysq/ProtoSq.h
@@ -65,7 +65,7 @@ namespace tidysq {
 
         inline bool operator==(const ProtoSq<INTERNAL, PROTO> &other) const {
            if ((alphabet_ != other.alphabet_) || (content_.size() != other.content_.size())) return false;
-           for (typeof(content_.size()) i = 0; i < content_.size(); i++) {
+           for (LenSq i = 0; i < content_.size(); i++) {
                if ((*this)[i] != other[i]) return false;
            }
            return true;
diff --git a/inst/include/tidysq/sqapply.h b/inst/include/tidysq/sqapply.h
index e9794af..63b23aa 100644
--- a/inst/include/tidysq/sqapply.h
+++ b/inst/include/tidysq/sqapply.h
@@ -10,7 +10,7 @@ namespace tidysq {
                        ops::OperationVectorToVector<VECTOR_IN, ELEMENT_IN, VECTOR_OUT, ELEMENT_OUT> &operation) {
         if (operation.may_return_early(vector_in)) return operation.return_early(vector_in);
         VECTOR_OUT ret = operation.initialize_vector_out(vector_in);
-        for (typeof(vector_in.size()) i = 0; i < vector_in.size(); i++) {
+        for (LenSq i = 0; i < vector_in.size(); i++) {
             ret[i] = operation(vector_in[i]);
         }
         return ret;