diff --git a/daemon/common/config-file.hpp b/daemon/common/config-file.hpp
index c58de29..39cc2ed 100644
--- a/daemon/common/config-file.hpp
+++ b/daemon/common/config-file.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2021,  Regents of the University of California,
+ * Copyright (c) 2014-2022,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -105,9 +105,9 @@
   static T
   parseNumber(const ConfigSection& node, const std::string& key, const std::string& sectionName)
   {
-    static_assert(std::is_arithmetic<T>::value, "T must be an arithmetic type");
+    static_assert(std::is_arithmetic_v<T>);
 
-    boost::optional<T> value = node.get_value_optional<T>();
+    auto value = node.get_value_optional<T>();
     // Unsigned logic is workaround for https://redmine.named-data.net/issues/4489
     if (value &&
         (std::is_signed<T>() || node.get_value<std::string>().find("-") == std::string::npos)) {
@@ -132,7 +132,7 @@
   static void
   checkRange(T value, T min, T max, const std::string& key, const std::string& sectionName)
   {
-    static_assert(std::is_integral<T>::value, "T must be an integral type");
+    static_assert(std::is_integral_v<T>);
 
     if (value < min || value > max) {
       NDN_THROW(Error("Invalid value '" + to_string(value) + "' for option '" + key +