diff --git a/libraries/http_client/http_client/http_client.hh b/libraries/http_client/http_client/http_client.hh
index 6c66ad7..a879363 100644
--- a/libraries/http_client/http_client/http_client.hh
+++ b/libraries/http_client/http_client/http_client.hh
@@ -1,5 +1,7 @@
 #pragma once
+#ifndef CURL_STATICLIB
 #define CURL_STATICLIB
+#endif  // CURL_STATICLIB
 #pragma comment(lib, "crypt32")
 #pragma comment(lib, "ws2_32.lib")
 #pragma comment(lib, "Wldap32.lib")
diff --git a/libraries/http_server/http_server/api.hh b/libraries/http_server/http_server/api.hh
index 0746779..32cbcb2 100644
--- a/libraries/http_server/http_server/api.hh
+++ b/libraries/http_server/http_server/api.hh
@@ -24,7 +24,7 @@ template <typename Req, typename Resp> struct api {
 
   typedef api<Req, Resp> self;
 
-  api(): is_global_handler(false), global_handler_(nullptr) { }
+  api() : is_global_handler(false), global_handler_(nullptr) {}
 
   using H = std::function<void(Req&, Resp&)>;
   struct VH {
@@ -65,7 +65,9 @@ template <typename Req, typename Resp> struct api {
 
   void add_subapi(std::string prefix, const self& subapi) {
     subapi.routes_map_.for_all_routes([this, prefix](auto r, VH h) {
-      if (!r.empty() && r.back() == '/')
+      if (r.empty() || r == "/")
+        h.url_spec = prefix;
+      else if (r.back() == '/')
         h.url_spec = prefix + r;
       else
         h.url_spec = prefix + '/' + r;
@@ -83,13 +85,11 @@ template <typename Req, typename Resp> struct api {
     std::cout << std::endl;
   }
   auto call(std::string_view method, std::string_view route, Req& request, Resp& response) const {
-    if(is_global_handler)
-    {
-        global_handler_(request, response);
-        return;
+    if (is_global_handler) {
+      global_handler_(request, response);
+      return;
     }
-    if (route == last_called_route_)
-    {
+    if (route == last_called_route_) {
       if (last_handler_.verb == ANY or parse_verb(method) == last_handler_.verb) {
         request.url_spec = last_handler_.url_spec;
         last_handler_.handler(request, response);
@@ -100,7 +100,8 @@ template <typename Req, typename Resp> struct api {
 
     // skip the last / of the url and trim spaces.
     std::string_view route2(route);
-    while (route2.size() > 1 and (route2[route2.size() - 1] == '/' || route2[route2.size() - 1] == ' '))
+    while (route2.size() > 1 and
+           (route2[route2.size() - 1] == '/' || route2[route2.size() - 1] == ' '))
       route2 = route2.substr(0, route2.size() - 1);
 
     auto it = routes_map_.find(route2);
diff --git a/libraries/http_server/tests/subapi.cc b/libraries/http_server/tests/subapi.cc
index 4141e18..666850c 100644
--- a/libraries/http_server/tests/subapi.cc
+++ b/libraries/http_server/tests/subapi.cc
@@ -6,20 +6,24 @@ using namespace li;
 
 int main() {
 
-  http_api my_api;
-  my_api.get("/") = [&](http_request& request, http_response& response) {
-    response.write("hello world.");
+  http_api root;
+  root.get("/") = [&](http_request& request, http_response& response) { response.write("root"); };
+
+  http_api subapi;
+  subapi.get("/") = [&](http_request& request, http_response& response) {
+    response.write("hello");
   };
 
-  http_api my_api2;
-  my_api2.get("/hello_world") = [&](http_request& request, http_response& response) {
-    response.write("hello world2.");
+  subapi.get("/world") = [&](http_request& request, http_response& response) {
+    response.write("hello world");
   };
 
-  my_api.add_subapi("/sub", my_api2);
+  root.add_subapi("/hello", subapi);
 
-  http_serve(my_api, 12334, s::non_blocking);
-  assert(http_get("http://localhost:12334").body == "hello world.");
-  assert(http_get("http://localhost:12334/").body == "hello world.");
-  assert(http_get("http://localhost:12334/sub/hello_world").body == "hello world2.");
+  http_serve(root, 12334, s::non_blocking);
+  assert(http_get("http://localhost:12334").body == "root");
+  assert(http_get("http://localhost:12334/").body == "root");
+  assert(http_get("http://localhost:12334/hello").body == "hello");
+  assert(http_get("http://localhost:12334/hello/").body == "hello");
+  assert(http_get("http://localhost:12334/hello/world").body == "hello world");
 }
diff --git a/libraries/sql/sql/sql_database.hh b/libraries/sql/sql/sql_database.hh
index 12628b2..a0dabd1 100644
--- a/libraries/sql/sql/sql_database.hh
+++ b/libraries/sql/sql/sql_database.hh
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <deque>
+#include <functional>
 #include <unordered_map>
 
 namespace li {
@@ -211,4 +212,4 @@ template <typename I> struct sql_database {
   inline auto connect() { active_yield yield; return this->connect(yield); }
 };
 
-}
\ No newline at end of file
+}
diff --git a/single_headers/lithium.hh b/single_headers/lithium.hh
index 9e0139d..6709f9e 100644
--- a/single_headers/lithium.hh
+++ b/single_headers/lithium.hh
@@ -1821,7 +1821,9 @@ struct sqlite_database {
 
 #ifndef LITHIUM_SINGLE_HEADER_GUARD_LI_HTTP_CLIENT_HTTP_CLIENT_HH
 #define LITHIUM_SINGLE_HEADER_GUARD_LI_HTTP_CLIENT_HTTP_CLIENT_HH
+#ifndef CURL_STATICLIB
 #define CURL_STATICLIB
+#endif  // CURL_STATICLIB
 #pragma comment(lib, "crypt32")
 #pragma comment(lib, "ws2_32.lib")
 #pragma comment(lib, "Wldap32.lib")
@@ -5490,6 +5492,7 @@ template <typename I> struct sql_database {
 };
 
 }
+
 #endif // LITHIUM_SINGLE_HEADER_GUARD_LI_SQL_SQL_DATABASE_HH
 
 
@@ -6834,7 +6837,7 @@ template <typename Req, typename Resp> struct api {
 
   typedef api<Req, Resp> self;
 
-  api(): is_global_handler(false), global_handler_(nullptr) { }
+  api() : is_global_handler(false), global_handler_(nullptr) {}
 
   using H = std::function<void(Req&, Resp&)>;
   struct VH {
@@ -6875,7 +6878,9 @@ template <typename Req, typename Resp> struct api {
 
   void add_subapi(std::string prefix, const self& subapi) {
     subapi.routes_map_.for_all_routes([this, prefix](auto r, VH h) {
-      if (!r.empty() && r.back() == '/')
+      if (r.empty() || r == "/")
+        h.url_spec = prefix;
+      else if (r.back() == '/')
         h.url_spec = prefix + r;
       else
         h.url_spec = prefix + '/' + r;
@@ -6893,13 +6898,11 @@ template <typename Req, typename Resp> struct api {
     std::cout << std::endl;
   }
   auto call(std::string_view method, std::string_view route, Req& request, Resp& response) const {
-    if(is_global_handler)
-    {
-        global_handler_(request, response);
-        return;
+    if (is_global_handler) {
+      global_handler_(request, response);
+      return;
     }
-    if (route == last_called_route_)
-    {
+    if (route == last_called_route_) {
       if (last_handler_.verb == ANY or parse_verb(method) == last_handler_.verb) {
         request.url_spec = last_handler_.url_spec;
         last_handler_.handler(request, response);
@@ -6910,7 +6913,8 @@ template <typename Req, typename Resp> struct api {
 
     // skip the last / of the url and trim spaces.
     std::string_view route2(route);
-    while (route2.size() > 1 and (route2[route2.size() - 1] == '/' || route2[route2.size() - 1] == ' '))
+    while (route2.size() > 1 and
+           (route2[route2.size() - 1] == '/' || route2[route2.size() - 1] == ' '))
       route2 = route2.substr(0, route2.size() - 1);
 
     auto it = routes_map_.find(route2);
diff --git a/single_headers/lithium_http_client.hh b/single_headers/lithium_http_client.hh
index f22e0c8..07dda67 100644
--- a/single_headers/lithium_http_client.hh
+++ b/single_headers/lithium_http_client.hh
@@ -32,7 +32,9 @@
 
 #ifndef LITHIUM_SINGLE_HEADER_GUARD_LI_HTTP_CLIENT_HTTP_CLIENT_HH
 #define LITHIUM_SINGLE_HEADER_GUARD_LI_HTTP_CLIENT_HTTP_CLIENT_HH
+#ifndef CURL_STATICLIB
 #define CURL_STATICLIB
+#endif  // CURL_STATICLIB
 #pragma comment(lib, "crypt32")
 #pragma comment(lib, "ws2_32.lib")
 #pragma comment(lib, "Wldap32.lib")
diff --git a/single_headers/lithium_http_server.hh b/single_headers/lithium_http_server.hh
index 1266d16..7f4700a 100644
--- a/single_headers/lithium_http_server.hh
+++ b/single_headers/lithium_http_server.hh
@@ -3654,7 +3654,7 @@ template <typename Req, typename Resp> struct api {
 
   typedef api<Req, Resp> self;
 
-  api(): is_global_handler(false), global_handler_(nullptr) { }
+  api() : is_global_handler(false), global_handler_(nullptr) {}
 
   using H = std::function<void(Req&, Resp&)>;
   struct VH {
@@ -3695,7 +3695,9 @@ template <typename Req, typename Resp> struct api {
 
   void add_subapi(std::string prefix, const self& subapi) {
     subapi.routes_map_.for_all_routes([this, prefix](auto r, VH h) {
-      if (!r.empty() && r.back() == '/')
+      if (r.empty() || r == "/")
+        h.url_spec = prefix;
+      else if (r.back() == '/')
         h.url_spec = prefix + r;
       else
         h.url_spec = prefix + '/' + r;
@@ -3713,13 +3715,11 @@ template <typename Req, typename Resp> struct api {
     std::cout << std::endl;
   }
   auto call(std::string_view method, std::string_view route, Req& request, Resp& response) const {
-    if(is_global_handler)
-    {
-        global_handler_(request, response);
-        return;
+    if (is_global_handler) {
+      global_handler_(request, response);
+      return;
     }
-    if (route == last_called_route_)
-    {
+    if (route == last_called_route_) {
       if (last_handler_.verb == ANY or parse_verb(method) == last_handler_.verb) {
         request.url_spec = last_handler_.url_spec;
         last_handler_.handler(request, response);
@@ -3730,7 +3730,8 @@ template <typename Req, typename Resp> struct api {
 
     // skip the last / of the url and trim spaces.
     std::string_view route2(route);
-    while (route2.size() > 1 and (route2[route2.size() - 1] == '/' || route2[route2.size() - 1] == ' '))
+    while (route2.size() > 1 and
+           (route2[route2.size() - 1] == '/' || route2[route2.size() - 1] == ' '))
       route2 = route2.substr(0, route2.size() - 1);
 
     auto it = routes_map_.find(route2);
diff --git a/single_headers/lithium_mysql.hh b/single_headers/lithium_mysql.hh
index 35f7fce..14ae02c 100644
--- a/single_headers/lithium_mysql.hh
+++ b/single_headers/lithium_mysql.hh
@@ -13,6 +13,7 @@
 #include <cassert>
 #include <cstring>
 #include <deque>
+#include <functional>
 #include <iostream>
 #include <map>
 #include <memory>
@@ -2518,6 +2519,7 @@ template <typename I> struct sql_database {
 };
 
 }
+
 #endif // LITHIUM_SINGLE_HEADER_GUARD_LI_SQL_SQL_DATABASE_HH
 
 
diff --git a/single_headers/lithium_pgsql.hh b/single_headers/lithium_pgsql.hh
index 0811052..1a6240b 100644
--- a/single_headers/lithium_pgsql.hh
+++ b/single_headers/lithium_pgsql.hh
@@ -14,6 +14,7 @@
 #include <cassert>
 #include <cstring>
 #include <deque>
+#include <functional>
 #include <iostream>
 #if __APPLE__
 #include <libkern/OSByteOrder.h>
@@ -2192,6 +2193,7 @@ template <typename I> struct sql_database {
 };
 
 }
+
 #endif // LITHIUM_SINGLE_HEADER_GUARD_LI_SQL_SQL_DATABASE_HH