diff --git a/build.sh b/build.sh
index 516ff1f..e231cb0 100755
--- a/build.sh
+++ b/build.sh
@@ -5,7 +5,7 @@ if [ $1 = "build" ]; then
 
 elif [ $1 = "run" ]; then
     make main
-    ./output/main
+    ./output/main 5000 ./library
 
 elif [ $1 = "debug" ]; then
     echo "Debugging"
diff --git a/src/main.c b/src/main.c
index 28737e3..db541bf 100644
--- a/src/main.c
+++ b/src/main.c
@@ -5,7 +5,7 @@
 #define NOH_IMPLEMENTATION
 #include "noh.h"
 
-
+#define NO_AUTH
 /* To disable Basic auth for testing:
 #define NO_AUTH
 This will ignore any auth headers and always log in with username demo.
@@ -14,8 +14,6 @@ This will ignore any auth headers and always log in with username demo.
 #define SV Noh_String_View
 #define sv noh_sv_from_cstr
 
-Noh_Arena temp;
-
 static enum MHD_Result send_response(struct MHD_Connection *connection, int status, SV message) {
     struct MHD_Response *response = MHD_create_response_from_buffer(
         message.count, (void*)message.elems, MHD_RESPMEM_PERSISTENT);
@@ -26,13 +24,15 @@ static enum MHD_Result send_response(struct MHD_Connection *connection, int stat
     return ret;
 }
 
-static enum MHD_Result handle_opds(struct MHD_Connection *connection, SV url) {
+static enum MHD_Result handle_opds(struct MHD_Connection *connection, SV url, SV username) {
     (void)url;
+    (void)username;
     return send_response(connection, 200, sv("TODO: OPDS\n"));
 }
 
-static enum MHD_Result handle_get(struct MHD_Connection *connection, SV url) {
+static enum MHD_Result handle_get(struct MHD_Connection *connection, SV url, SV username) {
     (void)url;
+    (void)username;
     return send_response(connection, 200, sv("TODO: Get\n"));
 }
 
@@ -40,7 +40,7 @@ bool is_slash(const char c) { return c == '/'; }
 
 static enum MHD_Result request_handler(
         void *cls,
-        struct MHD_Connection *connection, 
+        struct MHD_Connection *connection,
         const char *_url, const char *method, const char *version,
         const char *upload_data, size_t *upload_data_size,
         void **con_cls) {
@@ -67,7 +67,7 @@ static enum MHD_Result request_handler(
     if (strcmp(method, "GET") != 0) return send_response(connection, 405, sv(""));
 
     SV url = sv(_url);
-    noh_sv_trim_left(&url, is_slash);;
+    noh_sv_trim_left(&url, is_slash);
     SV controller = noh_sv_chop_by_delim(&url, '/');
 
     if (noh_sv_eq_ci(controller, sv("opds"))) return handle_opds(connection, url, username);
@@ -75,18 +75,39 @@ static enum MHD_Result request_handler(
     return send_response(connection, 404, sv(""));
 }
 
+void show_usage(char *program_name, char *error) {
+    noh_log(NOH_INFO, "Usage:");
+    noh_log(NOH_INFO, "%s port library_path", program_name);
+    noh_log(NOH_INFO, "  port: The port to listen to, between 1000 and 65535.");
+    noh_log(NOH_INFO, "  library_path: The path where the epub libraries are located.");
+    noh_log(NOH_INFO, "              The root of this path should have a users.txt file with the usernames and passwords of valid users.");
+    noh_log(NOH_INFO, "              For each user, ther must be a subdirectory where this user's library is located.");
+    noh_log(NOH_INFO, "");
+    noh_log(NOH_ERROR, "%s", error);
+    exit(1);
+}
 
-int main(void)
+int main(int argc, char **argv)
 {
-    temp  = noh_arena_init(1 * 1024 * 1024);
+    // Parse input parameters.
+    char *program_name = noh_shift_args(&argc, &argv);
+
+    if (argc < 1) show_usage(program_name, "Port not provided.");
+    char *port_str = noh_shift_args(&argc, &argv);
+
+    int port = atoi(port_str);
+    if (port < 1000 || port > 65535) show_usage(program_name, "Invalid port.");
+
+    if (argc < 1) show_usage(program_name, "Library path not provided.");
+
     struct MHD_Daemon *server;
 
     // Start the HTTP server
     server = MHD_start_daemon(
         MHD_USE_INTERNAL_POLLING_THREAD,
-        5000, 
-        NULL, NULL, 
-        &request_handler, NULL, 
+        port,
+        NULL, NULL,
+        &request_handler, NULL,
         MHD_OPTION_END);
 
     if (!server) {
@@ -94,7 +115,7 @@ int main(void)
         return 1;
     }
 
-    printf("Server is running on http://localhost:5000\n");
+    printf("Server is running on http://localhost:%d\n", port);
 
     // Keep the server running
     getchar();