diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3699522b..2df3738a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,7 +6,7 @@ cmake_minimum_required(VERSION 3.8)
 
 project("Libmultiprocess" CXX)
 if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
-  set(CMAKE_CXX_STANDARD 17)
+  set(CMAKE_CXX_STANDARD 20)
   set(CMAKE_CXX_STANDARD_REQUIRED YES)
 endif()
 
diff --git a/example/calculator.cpp b/example/calculator.cpp
index 4290d687..ae69ce8a 100644
--- a/example/calculator.cpp
+++ b/example/calculator.cpp
@@ -3,6 +3,7 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <calculator.h>
+#include <charconv>
 #include <fstream>
 #include <init.capnp.h>
 #include <init.capnp.proxy.h> // NOLINT(misc-include-cleaner)
@@ -44,8 +45,12 @@ int main(int argc, char** argv)
         std::cout << "Usage: mpcalculator <fd>\n";
         return 1;
     }
+    int fd;
+    if (std::from_chars(argv[1], argv[1] + strlen(argv[1]), fd).ec != std::errc{}) {
+        std::cerr << argv[1] << " is not a number or is larger than an int\n";
+        return 1;
+    }
     mp::EventLoop loop("mpcalculator", LogPrint);
-    const int fd = std::stoi(argv[1]);
     std::unique_ptr<Init> init = std::make_unique<InitImpl>();
     mp::ServeStream<InitInterface>(loop, fd, *init);
     loop.loop();
diff --git a/example/example.cpp b/example/example.cpp
index a4f84c55..878ad4c5 100644
--- a/example/example.cpp
+++ b/example/example.cpp
@@ -3,6 +3,7 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <filesystem>
+#include <format>
 #include <fstream>
 #include <future>
 #include <init.capnp.h>
@@ -25,7 +26,7 @@ static auto Spawn(mp::EventLoop& loop, const std::string& process_argv0, const s
         fs::path path = process_argv0;
         path.remove_filename();
         path.append(new_exe_name);
-        return {path.string(), std::to_string(fd)};
+        return {path.string(), std::format("{:d}", fd)};
     });
     return std::make_tuple(mp::ConnectStream<InitInterface>(loop, fd), pid);
 }
diff --git a/example/printer.cpp b/example/printer.cpp
index ccaed689..9f85d450 100644
--- a/example/printer.cpp
+++ b/example/printer.cpp
@@ -2,6 +2,7 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include <charconv>
 #include <fstream>
 #include <init.capnp.h>
 #include <init.capnp.proxy.h> // NOLINT(misc-include-cleaner)
@@ -37,8 +38,12 @@ int main(int argc, char** argv)
         std::cout << "Usage: mpprinter <fd>\n";
         return 1;
     }
+    int fd;
+    if (std::from_chars(argv[1], argv[1] + strlen(argv[1]), fd).ec != std::errc{}) {
+        std::cerr << argv[1] << " is not a number or is larger than an int\n";
+        return 1;
+    }
     mp::EventLoop loop("mpprinter", LogPrint);
-    const int fd = std::stoi(argv[1]);
     std::unique_ptr<Init> init = std::make_unique<InitImpl>();
     mp::ServeStream<InitInterface>(loop, fd, *init);
     loop.loop();
diff --git a/src/mp/gen.cpp b/src/mp/gen.cpp
index c4d9a516..267c2837 100644
--- a/src/mp/gen.cpp
+++ b/src/mp/gen.cpp
@@ -13,6 +13,7 @@
 #include <errno.h>
 #include <fstream>
 #include <functional>
+#include <iostream>
 #include <kj/array.h>
 #include <kj/common.h>
 #include <kj/filesystem.h>
@@ -637,7 +638,7 @@ static void Generate(kj::StringPtr src_prefix,
 int main(int argc, char** argv)
 {
     if (argc < 3) {
-        fprintf(stderr, "Usage: " PROXY_BIN " SRC_PREFIX INCLUDE_PREFIX SRC_FILE [IMPORT_PATH...]\n");
+        std::cerr << "Usage: " << PROXY_BIN << " SRC_PREFIX INCLUDE_PREFIX SRC_FILE [IMPORT_PATH...]\n";
         exit(1);
     }
     std::vector<kj::StringPtr> import_paths;
diff --git a/src/mp/util.cpp b/src/mp/util.cpp
index 691ae0b3..15c40b33 100644
--- a/src/mp/util.cpp
+++ b/src/mp/util.cpp
@@ -6,6 +6,7 @@
 #include <mp/util.h>
 
 #include <errno.h>
+#include <format>
 #include <kj/common.h>
 #include <kj/string-tree.h>
 #include <pthread.h>
@@ -85,9 +86,7 @@ std::string LogEscape(const kj::StringTree& string)
             if (c == '\\') {
                 result.append("\\\\");
             } else if (c < 0x20 || c > 0x7e) {
-                char escape[4];
-                snprintf(escape, 4, "\\%02x", c);
-                result.append(escape);
+                result.append(std::format("\\{:02x}", c));
             } else {
                 result.push_back(c);
             }
diff --git a/test/mp/test/test.cpp b/test/mp/test/test.cpp
index 7721d41f..7fc64f67 100644
--- a/test/mp/test/test.cpp
+++ b/test/mp/test/test.cpp
@@ -11,6 +11,7 @@
 #include <cstdio>
 #include <future>
 #include <functional>
+#include <iostream>
 #include <memory>
 #include <kj/common.h>
 #include <kj/memory.h>
@@ -27,7 +28,9 @@ KJ_TEST("Call FooInterface methods")
     std::promise<std::unique_ptr<ProxyClient<messages::FooInterface>>> foo_promise;
     std::function<void()> disconnect_client;
     std::thread thread([&]() {
-        EventLoop loop("mptest", [](bool raise, const std::string& log) { printf("LOG%i: %s\n", raise, log.c_str()); });
+        EventLoop loop("mptest", [](bool raise, const std::string& log) {
+            std::cout << "LOG" << raise << ": " << log << "\n";
+        });
         auto pipe = loop.m_io_context.provider->newTwoWayPipe();
 
         auto connection_client = std::make_unique<Connection>(loop, kj::mv(pipe.ends[0]));