diff --git a/bindings/python/src/alert.cpp b/bindings/python/src/alert.cpp
index 39af92772..db35efffd 100644
--- a/bindings/python/src/alert.cpp
+++ b/bindings/python/src/alert.cpp
@@ -256,6 +256,7 @@ namespace boost
 }
 
 struct dummy3 {};
+struct dummy12 {};
 
 bytes get_pkt_buf(dht_pkt_alert const& alert)
 {
@@ -329,6 +330,34 @@ void bind_alert()
         s.attr("all_categories") = alert::all_categories;
     }
 
+    {
+        scope s = class_<dummy12>("alert_category");
+        s.attr("error") = alert_category::error;
+        s.attr("peer") = alert_category::peer;
+        s.attr("port_mapping") = alert_category::port_mapping;
+        s.attr("storage") = alert_category::storage;
+        s.attr("tracker") = alert_category::tracker;
+        s.attr("connect") = alert_category::connect;
+        s.attr("status") = alert_category::status;
+        s.attr("ip_block") = alert_category::ip_block;
+        s.attr("performance_warning") = alert_category::performance_warning;
+        s.attr("dht") = alert_category::dht;
+        s.attr("stats") = alert_category::stats;
+        s.attr("session_log") = alert_category::session_log;
+        s.attr("torrent_log") = alert_category::torrent_log;
+        s.attr("peer_log") = alert_category::peer_log;
+        s.attr("incoming_request") = alert_category::incoming_request;
+        s.attr("dht_log") = alert_category::dht_log;
+        s.attr("dht_operation") = alert_category::dht_operation;
+        s.attr("port_mapping_log") = alert_category::port_mapping_log;
+        s.attr("picker_log") = alert_category::picker_log;
+        s.attr("file_progress") = alert_category::file_progress;
+        s.attr("piece_progress") = alert_category::piece_progress;
+        s.attr("upload") = alert_category::upload;
+        s.attr("block_progress") = alert_category::block_progress;
+        s.attr("all") = alert_category::all;
+    }
+
     enum_<operation_t>("operation_t")
        .value("unknown", operation_t::unknown)
        .value("bittorrent", operation_t::bittorrent)
diff --git a/docs/gen_reference_doc.py b/docs/gen_reference_doc.py
index f05bf0ce6..44bc031e1 100644
--- a/docs/gen_reference_doc.py
+++ b/docs/gen_reference_doc.py
@@ -80,7 +80,8 @@ static_links = \
     {
         ".. _`BEP 3`: https://www.bittorrent.org/beps/bep_0003.html",
         ".. _`BEP 17`: https://www.bittorrent.org/beps/bep_0017.html",
-        ".. _`BEP 19`: https://www.bittorrent.org/beps/bep_0019.html"
+        ".. _`BEP 19`: https://www.bittorrent.org/beps/bep_0019.html",
+        ".. _`BEP 42`: https://www.bittorrent.org/beps/bep_0042.html"
     }
 
 anon_index = 0
@@ -1101,6 +1102,7 @@ def linkify_symbols(string):
     ret = []
     in_literal = False
     lno = 0
+    return_string = ''
     for line in lines:
         lno += 1
         # don't touch headlines, i.e. lines whose
@@ -1110,6 +1112,12 @@ def linkify_symbols(string):
         else:
             next_line = ''
 
+        if '.. include:: ' in line:
+            return_string += '\n'.join(ret)
+            ret = [line]
+            return_string += dump_link_targets() + '\n'
+            continue
+
         if len(next_line) > 0 and lines[lno].replace('=', ''). \
                 replace('-', '').replace('.', '') == '':
             ret.append(line)
@@ -1174,7 +1182,8 @@ def linkify_symbols(string):
                 # print('  found %s -> %s' % (w, link_name))
                 words[i] = leading + print_link(link_name, symbols[w]) + trailing
         ret.append(' '.join(words))
-    return '\n'.join(ret)
+    return_string += '\n'.join(ret)
+    return return_string
 
 
 link_targets = []
diff --git a/examples/bt-get.cpp b/examples/bt-get.cpp
index d951b7ac1..e6aa8ebed 100644
--- a/examples/bt-get.cpp
+++ b/examples/bt-get.cpp
@@ -47,8 +47,8 @@ int main(int argc, char const* argv[]) try
 		return 1;
 	}
 	lt::settings_pack p;
-	p.set_int(lt::settings_pack::alert_mask, lt::alert::status_notification
-		| lt::alert::error_notification);
+	p.set_int(lt::settings_pack::alert_mask, lt::alert_category::status
+		| lt::alert_category::error);
 	lt::session ses(p);
 
 	lt::add_torrent_params atp = lt::parse_magnet_uri(argv[1]);
diff --git a/examples/bt-get2.cpp b/examples/bt-get2.cpp
index 6853c8e72..cbba225bd 100644
--- a/examples/bt-get2.cpp
+++ b/examples/bt-get2.cpp
@@ -72,9 +72,9 @@ int main(int argc, char const* argv[]) try
 
 	lt::settings_pack pack;
 	pack.set_int(lt::settings_pack::alert_mask
-		, lt::alert::error_notification
-		| lt::alert::storage_notification
-		| lt::alert::status_notification);
+		, lt::alert_category::error
+		| lt::alert_category::storage
+		| lt::alert_category::status);
 
 	lt::session ses(pack);
 	clk::time_point last_save_resume = clk::now();
diff --git a/examples/client_test.cpp b/examples/client_test.cpp
index a5365726b..793e0f1a9 100644
--- a/examples/client_test.cpp
+++ b/examples/client_test.cpp
@@ -582,29 +582,29 @@ void assign_setting(lt::settings_pack& settings, std::string const& key, char co
 			}
 
 			static std::map<lt::string_view, lt::alert_category_t> const alert_categories = {
-				{"error"_sv, alert::error_notification},
-				{"peer"_sv, alert::peer_notification},
-				{"port_mapping"_sv, alert::port_mapping_notification},
-				{"storage"_sv, alert::storage_notification},
-				{"tracker"_sv, alert::tracker_notification},
-				{"connect"_sv, alert::connect_notification},
-				{"status"_sv, alert::status_notification},
-				{"ip_block"_sv, alert::ip_block_notification},
-				{"performance_warning"_sv, alert::performance_warning},
-				{"dht"_sv, alert::dht_notification},
-				{"session_log"_sv, alert::session_log_notification},
-				{"torrent_log"_sv, alert::torrent_log_notification},
-				{"peer_log"_sv, alert::peer_log_notification},
-				{"incoming_request"_sv, alert::incoming_request_notification},
-				{"dht_log"_sv, alert::dht_log_notification},
-				{"dht_operation"_sv, alert::dht_operation_notification},
-				{"port_mapping_log"_sv, alert::port_mapping_log_notification},
-				{"picker_log"_sv, alert::picker_log_notification},
-				{"file_progress"_sv, alert::file_progress_notification},
-				{"piece_progress"_sv, alert::piece_progress_notification},
-				{"upload"_sv, alert::upload_notification},
-				{"block_progress"_sv, alert::block_progress_notification},
-				{"all"_sv, alert::all_categories},
+				{"error"_sv, lt::alert_category::error},
+				{"peer"_sv, lt::alert_category::peer},
+				{"port_mapping"_sv, lt::alert_category::port_mapping},
+				{"storage"_sv, lt::alert_category::storage},
+				{"tracker"_sv, lt::alert_category::tracker},
+				{"connect"_sv, lt::alert_category::connect},
+				{"status"_sv, lt::alert_category::status},
+				{"ip_block"_sv, lt::alert_category::ip_block},
+				{"performance_warning"_sv, lt::alert_category::performance_warning},
+				{"dht"_sv, lt::alert_category::dht},
+				{"session_log"_sv, lt::alert_category::session_log},
+				{"torrent_log"_sv, lt::alert_category::torrent_log},
+				{"peer_log"_sv, lt::alert_category::peer_log},
+				{"incoming_request"_sv, lt::alert_category::incoming_request},
+				{"dht_log"_sv, lt::alert_category::dht_log},
+				{"dht_operation"_sv, lt::alert_category::dht_operation},
+				{"port_mapping_log"_sv, lt::alert_category::port_mapping_log},
+				{"picker_log"_sv, lt::alert_category::picker_log},
+				{"file_progress"_sv, lt::alert_category::file_progress},
+				{"piece_progress"_sv, lt::alert_category::piece_progress},
+				{"upload"_sv, lt::alert_category::upload},
+				{"block_progress"_sv, lt::alert_category::block_progress},
+				{"all"_sv, lt::alert_category::all},
 			};
 
 			std::stringstream flags(value);
@@ -803,11 +803,11 @@ void print_alert(lt::alert const* a, std::string& str)
 {
 	using namespace lt;
 
-	if (a->category() & alert::error_notification)
+	if (a->category() & alert_category::error)
 	{
 		str += esc("31");
 	}
-	else if (a->category() & (alert::peer_notification | alert::storage_notification))
+	else if (a->category() & (alert_category::peer | alert_category::storage))
 	{
 		str += esc("33");
 	}
@@ -1211,20 +1211,20 @@ examples:
 
 	settings.set_str(settings_pack::user_agent, "client_test/" LIBTORRENT_VERSION);
 	settings.set_int(settings_pack::alert_mask
-		, alert::error_notification
-		| alert::peer_notification
-		| alert::port_mapping_notification
-		| alert::storage_notification
-		| alert::tracker_notification
-		| alert::connect_notification
-		| alert::status_notification
-		| alert::ip_block_notification
-		| alert::performance_warning
-		| alert::dht_notification
-		| alert::incoming_request_notification
-		| alert::dht_operation_notification
-		| alert::port_mapping_log_notification
-		| alert::file_progress_notification);
+		, lt::alert_category::error
+		| lt::alert_category::peer
+		| lt::alert_category::port_mapping
+		| lt::alert_category::storage
+		| lt::alert_category::tracker
+		| lt::alert_category::connect
+		| lt::alert_category::status
+		| lt::alert_category::ip_block
+		| lt::alert_category::performance_warning
+		| lt::alert_category::dht
+		| lt::alert_category::incoming_request
+		| lt::alert_category::dht_operation
+		| lt::alert_category::port_mapping_log
+		| lt::alert_category::file_progress);
 
 	lt::time_duration refresh_delay = lt::milliseconds(500);
 	bool rate_limit_locals = false;
diff --git a/examples/upnp_test.cpp b/examples/upnp_test.cpp
index 65e4d2abf..78700eb44 100644
--- a/examples/upnp_test.cpp
+++ b/examples/upnp_test.cpp
@@ -73,7 +73,7 @@ int main(int argc, char*[])
 	}
 
 	settings_pack p;
-	p.set_int(settings_pack::alert_mask, alert::port_mapping_notification);
+	p.set_int(settings_pack::alert_mask, alert_category::port_mapping);
 	lt::session s(p);
 
 	for (;;)
diff --git a/fuzzers/src/peer_conn.cpp b/fuzzers/src/peer_conn.cpp
index 8586be7e9..0e50486c4 100644
--- a/fuzzers/src/peer_conn.cpp
+++ b/fuzzers/src/peer_conn.cpp
@@ -73,10 +73,10 @@ extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv)
 #ifdef DEBUG_LOGGING
 	pack.set_int(settings_pack::alert_mask, 0xffffff);
 #else
-	pack.set_int(settings_pack::alert_mask, alert::connect_notification
-		| alert::error_notification
-		| alert::status_notification
-		| alert::peer_notification);
+	pack.set_int(settings_pack::alert_mask, alert_category::connect
+		| alert_category::error
+		| alert_category::status
+		| alert_category::peer);
 #endif
 
 	pack.set_int(settings_pack::out_enc_policy, settings_pack::pe_disabled);
diff --git a/include/libtorrent/alert.hpp b/include/libtorrent/alert.hpp
index 5fe9e8c79..e10dfe775 100644
--- a/include/libtorrent/alert.hpp
+++ b/include/libtorrent/alert.hpp
@@ -67,8 +67,119 @@ POSSIBILITY OF SUCH DAMAGE.
 
 namespace libtorrent {
 
-	// hidden
-	using alert_category_t = flags::bitfield_flag<std::uint32_t, struct alert_category_tag>;
+// bitmask type used to define alert categories. Categories can be enabled
+// and disabled by the settings_pack::alert_mask setting. Constants are defined
+// in the lt::alert_category namespace
+using alert_category_t = flags::bitfield_flag<std::uint32_t, struct alert_category_tag>;
+
+namespace alert_category {
+
+	// Enables alerts that report an error. This includes:
+	//
+	// * tracker errors
+	// * tracker warnings
+	// * file errors
+	// * resume data failures
+	// * web seed errors
+	// * .torrent files errors
+	// * listen socket errors
+	// * port mapping errors
+	constexpr alert_category_t error = 0_bit;
+
+	// Enables alerts when peers send invalid requests, get banned or
+	// snubbed.
+	constexpr alert_category_t peer = 1_bit;
+
+	// Enables alerts for port mapping events. For NAT-PMP and UPnP.
+	constexpr alert_category_t port_mapping = 2_bit;
+
+	// Enables alerts for events related to the storage. File errors and
+	// synchronization events for moving the storage, renaming files etc.
+	constexpr alert_category_t storage = 3_bit;
+
+	// Enables all tracker events. Includes announcing to trackers,
+	// receiving responses, warnings and errors.
+	constexpr alert_category_t tracker = 4_bit;
+
+	// Low level alerts for when peers are connected and disconnected.
+	constexpr alert_category_t connect = 5_bit;
+
+		// Enables alerts for when a torrent or the session changes state.
+	constexpr alert_category_t status = 6_bit;
+
+	// Alerts when a peer is blocked by the ip blocker or port blocker.
+	constexpr alert_category_t ip_block = 8_bit;
+
+	// Alerts when some limit is reached that might limit the download
+	// or upload rate.
+	constexpr alert_category_t performance_warning = 9_bit;
+
+	// Alerts on events in the DHT node. For incoming searches or
+	// bootstrapping being done etc.
+	constexpr alert_category_t dht = 10_bit;
+
+	// If you enable these alerts, you will receive a stats_alert
+	// approximately once every second, for every active torrent.
+	// These alerts contain all statistics counters for the interval since
+	// the lasts stats alert.
+	constexpr alert_category_t stats = 11_bit;
+
+	// Enables debug logging alerts. These are available unless libtorrent
+	// was built with logging disabled (``TORRENT_DISABLE_LOGGING``). The
+	// alerts being posted are log_alert and are session wide.
+	constexpr alert_category_t session_log = 13_bit;
+
+	// Enables debug logging alerts for torrents. These are available
+	// unless libtorrent was built with logging disabled
+	// (``TORRENT_DISABLE_LOGGING``). The alerts being posted are
+	// torrent_log_alert and are torrent wide debug events.
+	constexpr alert_category_t torrent_log = 14_bit;
+
+	// Enables debug logging alerts for peers. These are available unless
+	// libtorrent was built with logging disabled
+	// (``TORRENT_DISABLE_LOGGING``). The alerts being posted are
+	// peer_log_alert and low-level peer events and messages.
+	constexpr alert_category_t peer_log = 15_bit;
+
+	// enables the incoming_request_alert.
+	constexpr alert_category_t incoming_request = 16_bit;
+
+	// enables dht_log_alert, debug logging for the DHT
+	constexpr alert_category_t dht_log = 17_bit;
+
+	// enable events from pure dht operations not related to torrents
+	constexpr alert_category_t dht_operation = 18_bit;
+
+	// enables port mapping log events. This log is useful
+	// for debugging the UPnP or NAT-PMP implementation
+	constexpr alert_category_t port_mapping_log = 19_bit;
+
+	// enables verbose logging from the piece picker.
+	constexpr alert_category_t picker_log = 20_bit;
+
+	// alerts when files complete downloading
+	constexpr alert_category_t file_progress = 21_bit;
+
+	// alerts when pieces complete downloading or fail hash check
+	constexpr alert_category_t piece_progress = 22_bit;
+
+	// alerts when we upload blocks to other peers
+	constexpr alert_category_t upload = 23_bit;
+
+	// alerts on individual blocks being requested, downloading, finished,
+	// rejected, time-out and cancelled. This is likely to post alerts at a
+	// high rate.
+	constexpr alert_category_t block_progress = 24_bit;
+
+	// The full bitmask, representing all available categories.
+	//
+	// since the enum is signed, make sure this isn't
+	// interpreted as -1. For instance, boost.python
+	// does that and fails when assigning it to an
+	// unsigned parameter.
+	constexpr alert_category_t all = alert_category_t::all();
+
+} // namespace alert_category
 
 #ifdef __GNUC__
 #pragma GCC diagnostic push
@@ -98,125 +209,38 @@ namespace libtorrent {
 		using category_t = alert_category_t;
 #endif
 
-		// Enables alerts that report an error. This includes:
-		//
-		// * tracker errors
-		// * tracker warnings
-		// * file errors
-		// * resume data failures
-		// * web seed errors
-		// * .torrent files errors
-		// * listen socket errors
-		// * port mapping errors
 		static constexpr alert_category_t error_notification = 0_bit;
-
-		// Enables alerts when peers send invalid requests, get banned or
-		// snubbed.
 		static constexpr alert_category_t peer_notification = 1_bit;
-
-		// Enables alerts for port mapping events. For NAT-PMP and UPnP.
 		static constexpr alert_category_t port_mapping_notification = 2_bit;
-
-		// Enables alerts for events related to the storage. File errors and
-		// synchronization events for moving the storage, renaming files etc.
 		static constexpr alert_category_t storage_notification = 3_bit;
-
-		// Enables all tracker events. Includes announcing to trackers,
-		// receiving responses, warnings and errors.
 		static constexpr alert_category_t tracker_notification = 4_bit;
-
-		// Low level alerts for when peers are connected and disconnected.
 		static constexpr alert_category_t connect_notification = 5_bit;
 #if TORRENT_ABI_VERSION == 1
 		static constexpr alert_category_t TORRENT_DEPRECATED_MEMBER debug_notification = connect_notification;
 #endif
-
-		// Enables alerts for when a torrent or the session changes state.
 		static constexpr alert_category_t status_notification = 6_bit;
-
 #if TORRENT_ABI_VERSION == 1
-		// Alerts for when blocks are requested and completed. Also when
-		// pieces are completed.
 		static constexpr alert_category_t TORRENT_DEPRECATED_MEMBER progress_notification = 7_bit;
 #endif
-
-		// Alerts when a peer is blocked by the ip blocker or port blocker.
 		static constexpr alert_category_t ip_block_notification = 8_bit;
-
-		// Alerts when some limit is reached that might limit the download
-		// or upload rate.
 		static constexpr alert_category_t performance_warning = 9_bit;
-
-		// Alerts on events in the DHT node. For incoming searches or
-		// bootstrapping being done etc.
 		static constexpr alert_category_t dht_notification = 10_bit;
-
-		// If you enable these alerts, you will receive a stats_alert
-		// approximately once every second, for every active torrent.
-		// These alerts contain all statistics counters for the interval since
-		// the lasts stats alert.
 		static constexpr alert_category_t stats_notification = 11_bit;
-
 #if TORRENT_ABI_VERSION == 1
-		// Alerts on RSS related events, like feeds being updated, feed error
-		// conditions and successful RSS feed updates. Enabling this category
-		// will make you receive rss_alert alerts.
 		static constexpr alert_category_t TORRENT_DEPRECATED_MEMBER rss_notification = 12_bit;
 #endif
-
-		// Enables debug logging alerts. These are available unless libtorrent
-		// was built with logging disabled (``TORRENT_DISABLE_LOGGING``). The
-		// alerts being posted are log_alert and are session wide.
 		static constexpr alert_category_t session_log_notification = 13_bit;
-
-		// Enables debug logging alerts for torrents. These are available
-		// unless libtorrent was built with logging disabled
-		// (``TORRENT_DISABLE_LOGGING``). The alerts being posted are
-		// torrent_log_alert and are torrent wide debug events.
 		static constexpr alert_category_t torrent_log_notification = 14_bit;
-
-		// Enables debug logging alerts for peers. These are available unless
-		// libtorrent was built with logging disabled
-		// (``TORRENT_DISABLE_LOGGING``). The alerts being posted are
-		// peer_log_alert and low-level peer events and messages.
 		static constexpr alert_category_t peer_log_notification = 15_bit;
-
-		// enables the incoming_request_alert.
 		static constexpr alert_category_t incoming_request_notification = 16_bit;
-
-		// enables dht_log_alert, debug logging for the DHT
 		static constexpr alert_category_t dht_log_notification = 17_bit;
-
-		// enable events from pure dht operations not related to torrents
 		static constexpr alert_category_t dht_operation_notification = 18_bit;
-
-		// enables port mapping log events. This log is useful
-		// for debugging the UPnP or NAT-PMP implementation
 		static constexpr alert_category_t port_mapping_log_notification = 19_bit;
-
-		// enables verbose logging from the piece picker.
 		static constexpr alert_category_t picker_log_notification = 20_bit;
-
-		// alerts when files complete downloading
 		static constexpr alert_category_t file_progress_notification = 21_bit;
-
-		// alerts when pieces complete downloading or fail hash check
 		static constexpr alert_category_t piece_progress_notification = 22_bit;
-
-		// alerts when we upload blocks to other peers
 		static constexpr alert_category_t upload_notification = 23_bit;
-
-		// alerts on individual blocks being requested, downloading, finished,
-		// rejected, time-out and cancelled. This is likely to post alerts at a
-		// high rate.
 		static constexpr alert_category_t block_progress_notification = 24_bit;
-
-		// The full bitmask, representing all available categories.
-		//
-		// since the enum is signed, make sure this isn't
-		// interpreted as -1. For instance, boost.python
-		// does that and fails when assigning it to an
-		// unsigned parameter.
 		static constexpr alert_category_t all_categories = alert_category_t::all();
 
 		// hidden
diff --git a/include/libtorrent/alert_types.hpp b/include/libtorrent/alert_types.hpp
index 84c3ce74f..1652fd0db 100644
--- a/include/libtorrent/alert_types.hpp
+++ b/include/libtorrent/alert_types.hpp
@@ -233,7 +233,7 @@ TORRENT_VERSION_NAMESPACE_2
 		torrent_added_alert(aux::stack_allocator& alloc, torrent_handle const& h);
 
 		TORRENT_DEFINE_ALERT(torrent_added_alert, 3)
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 	};
 
@@ -265,7 +265,7 @@ TORRENT_VERSION_NAMESPACE_2
 			, torrent_handle const& h, sha1_hash const& ih);
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_removed_alert, 4, alert_priority_critical)
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 		sha1_hash info_hash;
 	};
@@ -288,7 +288,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(read_piece_alert, 5, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::storage;
 		std::string message() const override;
 
 		error_code const error;
@@ -316,7 +316,7 @@ TORRENT_VERSION_NAMESPACE_2
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #endif
 		static constexpr alert_category_t static_category =
-			alert::file_progress_notification
+			alert_category::file_progress
 			PROGRESS_NOTIFICATION
 		;
 #ifdef __GNUC__
@@ -338,7 +338,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(file_renamed_alert, 7, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::storage;
 		std::string message() const override;
 
 		char const* new_name() const;
@@ -374,7 +374,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(file_rename_failed_alert, 8, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::storage;
 
 		std::string message() const override;
 
@@ -481,7 +481,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(performance_alert, 9)
 
-		static constexpr alert_category_t static_category = alert::performance_warning;
+		static constexpr alert_category_t static_category = alert_category::performance_warning;
 
 		std::string message() const override;
 
@@ -498,7 +498,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(state_changed_alert, 10, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 
 		std::string message() const override;
 
@@ -527,7 +527,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(tracker_error_alert, 11, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::tracker_notification | alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::tracker | alert_category::error;
 		std::string message() const override;
 
 		int const times_in_row;
@@ -557,7 +557,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(tracker_warning_alert, 12)
 
-		static constexpr alert_category_t static_category = alert::tracker_notification | alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::tracker | alert_category::error;
 		std::string message() const override;
 
 		// the message associated with this warning
@@ -582,7 +582,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(scrape_reply_alert, 13, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::tracker_notification;
+		static constexpr alert_category_t static_category = alert_category::tracker;
 		std::string message() const override;
 
 		// the data returned in the scrape response. These numbers
@@ -606,7 +606,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(scrape_failed_alert, 14, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::tracker_notification | alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::tracker | alert_category::error;
 		std::string message() const override;
 
 		// the error itself. This may indicate that the tracker sent an error
@@ -639,7 +639,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(tracker_reply_alert, 15)
 
-		static constexpr alert_category_t static_category = alert::tracker_notification;
+		static constexpr alert_category_t static_category = alert_category::tracker;
 		std::string message() const override;
 
 		// tells how many peers the tracker returned in this response. This is
@@ -661,7 +661,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_reply_alert, 16)
 
-		static constexpr alert_category_t static_category = alert::dht_notification | alert::tracker_notification;
+		static constexpr alert_category_t static_category = alert_category::dht | alert_category::tracker;
 		std::string message() const override;
 
 		int const num_peers;
@@ -679,7 +679,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(tracker_announce_alert, 17)
 
-		static constexpr alert_category_t static_category = alert::tracker_notification;
+		static constexpr alert_category_t static_category = alert_category::tracker;
 		std::string message() const override;
 
 		// specifies what event was sent to the tracker. It is defined as:
@@ -701,7 +701,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(hash_failed_alert, 18)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 
 		piece_index_t const piece_index;
@@ -717,7 +717,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(peer_ban_alert, 19)
 
-		static constexpr alert_category_t static_category = alert::peer_notification;
+		static constexpr alert_category_t static_category = alert_category::peer;
 		std::string message() const override;
 	};
 
@@ -731,7 +731,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(peer_unsnubbed_alert, 20)
 
-		static constexpr alert_category_t static_category = alert::peer_notification;
+		static constexpr alert_category_t static_category = alert_category::peer;
 		std::string message() const override;
 	};
 
@@ -745,7 +745,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(peer_snubbed_alert, 21)
 
-		static constexpr alert_category_t static_category = alert::peer_notification;
+		static constexpr alert_category_t static_category = alert_category::peer;
 		std::string message() const override;
 	};
 
@@ -760,7 +760,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(peer_error_alert, 22)
 
-		static constexpr alert_category_t static_category = alert::peer_notification;
+		static constexpr alert_category_t static_category = alert_category::peer;
 		std::string message() const override;
 
 		// a 0-terminated string of the low-level operation that failed, or nullptr if
@@ -785,7 +785,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(peer_connect_alert, 23)
 
-		static constexpr alert_category_t static_category = alert::connect_notification;
+		static constexpr alert_category_t static_category = alert_category::connect;
 		std::string message() const override;
 
 		int const socket_type;
@@ -803,7 +803,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(peer_disconnected_alert, 24)
 
-		static constexpr alert_category_t static_category = alert::connect_notification;
+		static constexpr alert_category_t static_category = alert_category::connect;
 		std::string message() const override;
 
 		// the kind of socket this peer was connected over
@@ -838,7 +838,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(invalid_request_alert, 25)
 
-		static constexpr alert_category_t static_category = alert::peer_notification;
+		static constexpr alert_category_t static_category = alert_category::peer;
 		std::string message() const override;
 
 		// the request we received from the peer
@@ -867,7 +867,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_finished_alert, 26, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 	};
 
@@ -890,7 +890,7 @@ TORRENT_VERSION_NAMESPACE_2
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #endif
 		static constexpr alert_category_t static_category =
-			alert::piece_progress_notification
+			alert_category::piece_progress
 			PROGRESS_NOTIFICATION
 		;
 #ifdef __GNUC__
@@ -917,8 +917,8 @@ TORRENT_VERSION_NAMESPACE_2
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #endif
 		static constexpr alert_category_t static_category =
-			alert::block_progress_notification
-			| alert::peer_notification
+			alert_category::block_progress
+			| alert_category::peer
 			PROGRESS_NOTIFICATION
 		;
 #ifdef __GNUC__
@@ -945,8 +945,8 @@ TORRENT_VERSION_NAMESPACE_2
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #endif
 		static constexpr alert_category_t static_category =
-			alert::block_progress_notification
-			| alert::peer_notification
+			alert_category::block_progress
+			| alert_category::peer
 			PROGRESS_NOTIFICATION
 		;
 #ifdef __GNUC__
@@ -973,7 +973,7 @@ TORRENT_VERSION_NAMESPACE_2
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #endif
 		static constexpr alert_category_t static_category =
-			alert::block_progress_notification
+			alert_category::block_progress
 			PROGRESS_NOTIFICATION
 		;
 #ifdef __GNUC__
@@ -1000,7 +1000,7 @@ TORRENT_VERSION_NAMESPACE_2
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #endif
 		static constexpr alert_category_t static_category =
-			alert::block_progress_notification
+			alert_category::block_progress
 			PROGRESS_NOTIFICATION
 		;
 #ifdef __GNUC__
@@ -1026,7 +1026,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(unwanted_block_alert, 32)
 
-		static constexpr alert_category_t static_category = alert::peer_notification;
+		static constexpr alert_category_t static_category = alert_category::peer;
 		std::string message() const override;
 
 		int const block_index;
@@ -1046,7 +1046,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(storage_moved_alert, 33, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::storage;
 		std::string message() const override;
 
 		// the path the torrent was moved to
@@ -1071,7 +1071,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(storage_moved_failed_alert, 34, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::storage;
 		std::string message() const override;
 
 		error_code const error;
@@ -1108,7 +1108,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_deleted_alert, 35, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::storage;
 		std::string message() const override;
 
 		sha1_hash info_hash;
@@ -1124,8 +1124,8 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_delete_failed_alert, 36, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification
-			| alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::storage
+			| alert_category::error;
 		std::string message() const override;
 
 		// tells you why it failed.
@@ -1153,7 +1153,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(save_resume_data_alert, 37, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::storage;
 		std::string message() const override;
 
 		// the ``params`` structure is populated with the fields to be passed to
@@ -1177,8 +1177,8 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(save_resume_data_failed_alert, 38, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::storage_notification
-			| alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::storage
+			| alert_category::error;
 		std::string message() const override;
 
 		// the error code from the resume_data failure
@@ -1199,7 +1199,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_paused_alert, 39, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 	};
 
@@ -1212,7 +1212,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_resumed_alert, 40, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 	};
 
@@ -1225,7 +1225,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_checked_alert, 41, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 	};
 
@@ -1240,7 +1240,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(url_seed_alert, 42)
 
-		static constexpr alert_category_t static_category = alert::peer_notification | alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::peer | alert_category::error;
 		std::string message() const override;
 
 		// the error the web seed encountered. If this is not set, the server
@@ -1278,9 +1278,9 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(file_error_alert, 43, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::status_notification
-			| alert::error_notification
-			| alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::status
+			| alert_category::error
+			| alert_category::storage;
 		std::string message() const override;
 
 		// the error code describing the error.
@@ -1315,7 +1315,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(metadata_failed_alert, 44)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		// indicates what failed when parsing the metadata. This error is
@@ -1357,7 +1357,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(metadata_received_alert, 45)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 	};
 
@@ -1375,7 +1375,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(udp_error_alert, 46)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		// the source address associated with the error (if any)
@@ -1399,7 +1399,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(external_ip_alert, 47)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 
 		// the IP address that is believed to be our external IP
@@ -1458,7 +1458,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(listen_failed_alert, 48, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::status_notification | alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::status | alert_category::error;
 		std::string message() const override;
 
 		// the network device libtorrent attempted to listen on, or the IP address
@@ -1542,7 +1542,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(listen_succeeded_alert, 49, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 
 		// the address libtorrent ended up listening on. This address
@@ -1580,8 +1580,8 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(portmap_error_alert, 50)
 
-		static constexpr alert_category_t static_category = alert::port_mapping_notification
-			| alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::port_mapping
+			| alert_category::error;
 		std::string message() const override;
 
 		// refers to the mapping index of the port map that failed, i.e.
@@ -1613,7 +1613,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(portmap_alert, 51)
 
-		static constexpr alert_category_t static_category = alert::port_mapping_notification;
+		static constexpr alert_category_t static_category = alert_category::port_mapping;
 		std::string message() const override;
 
 		// refers to the mapping index of the port map that failed, i.e.
@@ -1646,7 +1646,7 @@ TORRENT_VERSION_NAMESPACE_2
 	// UPnP or NAT-PMP. They contain a log line and the type (0 = NAT-PMP
 	// and 1 = UPnP). Displaying these messages to an end user is only useful
 	// for debugging the UPnP or NAT-PMP implementation. This alert is only
-	// posted if the alert::port_mapping_log_notification flag is enabled in
+	// posted if the alert_category::port_mapping_log flag is enabled in
 	// the alert mask.
 	struct TORRENT_EXPORT portmap_log_alert final : alert
 	{
@@ -1655,7 +1655,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(portmap_log_alert, 52)
 
-		static constexpr alert_category_t static_category = alert::port_mapping_log_notification;
+		static constexpr alert_category_t static_category = alert_category::port_mapping_log;
 		std::string message() const override;
 
 		portmap_transport const map_transport;
@@ -1688,8 +1688,8 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(fastresume_rejected_alert, 53, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::status_notification
-			| alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::status
+			| alert_category::error;
 		std::string message() const override;
 
 		error_code error;
@@ -1730,7 +1730,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(peer_blocked_alert, 54)
 
-		static constexpr alert_category_t static_category = alert::ip_block_notification;
+		static constexpr alert_category_t static_category = alert_category::ip_block;
 		std::string message() const override;
 
 		enum reason_t
@@ -1759,7 +1759,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_announce_alert, 55)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 		std::string message() const override;
 
 		aux::noexcept_movable<address> ip;
@@ -1776,7 +1776,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_get_peers_alert, 56)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 		std::string message() const override;
 
 		sha1_hash info_hash;
@@ -1795,7 +1795,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(stats_alert, 57)
 
-		static constexpr alert_category_t static_category = alert::stats_notification;
+		static constexpr alert_category_t static_category = alert_category::stats;
 		std::string message() const override;
 
 		enum stats_channel
@@ -1846,7 +1846,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(cache_flushed_alert, 58, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::storage_notification;
+		static constexpr alert_category_t static_category = alert_category::storage;
 	};
 
 #if TORRENT_ABI_VERSION == 1
@@ -1873,7 +1873,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(anonymous_mode_alert, 59)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		enum kind_t
@@ -1908,7 +1908,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(lsd_peer_alert, 60)
 
-		static constexpr alert_category_t static_category = alert::peer_notification;
+		static constexpr alert_category_t static_category = alert_category::peer;
 		std::string message() const override;
 	};
 
@@ -1923,7 +1923,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(trackerid_alert, 61)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 
 		// The tracker ID returned by the tracker
@@ -1946,7 +1946,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_bootstrap_alert, 62)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 		std::string message() const override;
 	};
 
@@ -1959,7 +1959,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_error_alert, 64, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::error_notification | alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::error | alert_category::status;
 		std::string message() const override;
 
 		// specifies which error the torrent encountered.
@@ -1990,7 +1990,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_need_cert_alert, 65, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 #if TORRENT_ABI_VERSION == 1
 		error_code const TORRENT_DEPRECATED_MEMBER error;
@@ -2011,7 +2011,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(incoming_connection_alert, 66)
 
-		static constexpr alert_category_t static_category = alert::peer_notification;
+		static constexpr alert_category_t static_category = alert_category::peer;
 		std::string message() const override;
 
 		// tells you what kind of socket the connection was accepted
@@ -2051,7 +2051,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(add_torrent_alert, 67, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 
 		// a copy of the parameters used when adding the torrent, it can be used
@@ -2074,7 +2074,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(state_update_alert, 68, alert_priority_high)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 
 		// contains the torrent status of all torrents that changed since last
@@ -2101,7 +2101,7 @@ TORRENT_VERSION_NAMESPACE_2
 			, error_code const& ec);
 		TORRENT_DEFINE_ALERT(mmap_cache_alert, 69)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		error_code const error;
@@ -2149,7 +2149,7 @@ TORRENT_VERSION_NAMESPACE_2
 #endif
 #endif
 
-		static constexpr alert_category_t static_category = alert::stats_notification;
+		static constexpr alert_category_t static_category = alert_category::stats;
 		std::string message() const override;
 
 		// An array are a mix of *counters* and *gauges*, which meanings can be
@@ -2198,7 +2198,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(torrent_update_alert, 71, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::status_notification;
+		static constexpr alert_category_t static_category = alert_category::status;
 		std::string message() const override;
 
 		// ``old_ih`` and ``new_ih`` are the previous and new info-hash for the torrent, respectively.
@@ -2223,7 +2223,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_error_alert, 73)
 
-		static constexpr alert_category_t static_category = alert::error_notification | alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::error | alert_category::dht;
 		std::string message() const override;
 
 		// the error code
@@ -2254,7 +2254,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(dht_immutable_item_alert, 74, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 
 		std::string message() const override;
 
@@ -2277,7 +2277,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(dht_mutable_item_alert, 75, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 		std::string message() const override;
 
 		// the public key that was looked up
@@ -2318,7 +2318,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_put_alert, 76)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 		std::string message() const override;
 
 		// the target hash the item was stored under if this was an *immutable*
@@ -2347,7 +2347,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(i2p_alert, 77)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		// the error that occurred in the i2p SAM connection
@@ -2365,7 +2365,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_outgoing_get_peers_alert, 78)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 		std::string message() const override;
 
 		// the info_hash of the torrent we're looking for peers for.
@@ -2386,7 +2386,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 	// This alert is posted by some session wide event. Its main purpose is
 	// trouble shooting and debugging. It's not enabled by the default alert
-	// mask and is enabled by the ``alert::session_log_notification`` bit.
+	// mask and is enabled by the ``alert_category::session_log`` bit.
 	// Furthermore, it's by default disabled as a build configuration.
 	struct TORRENT_EXPORT log_alert final : alert
 	{
@@ -2396,7 +2396,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(log_alert, 79)
 
-		static constexpr alert_category_t static_category = alert::session_log_notification;
+		static constexpr alert_category_t static_category = alert_category::session_log;
 		std::string message() const override;
 
 		// returns the log message
@@ -2415,7 +2415,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 	// This alert is posted by torrent wide events. It's meant to be used for
 	// trouble shooting and debugging. It's not enabled by the default alert
-	// mask and is enabled by the ``alert::torrent_log_notification`` bit. By
+	// mask and is enabled by the ``alert_category::torrent_log`` bit. By
 	// default it is disabled as a build configuration.
 	struct TORRENT_EXPORT torrent_log_alert final : torrent_alert
 	{
@@ -2425,7 +2425,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(torrent_log_alert, 80)
 
-		static constexpr alert_category_t static_category = alert::torrent_log_notification;
+		static constexpr alert_category_t static_category = alert_category::torrent_log;
 		std::string message() const override;
 
 		// returns the log message
@@ -2443,7 +2443,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 	// This alert is posted by events specific to a peer. It's meant to be used
 	// for trouble shooting and debugging. It's not enabled by the default alert
-	// mask and is enabled by the ``alert::peer_log_notification`` bit. By
+	// mask and is enabled by the ``alert_category::peer_log`` bit. By
 	// default it is disabled as a build configuration.
 	struct TORRENT_EXPORT peer_log_alert final : peer_alert
 	{
@@ -2466,7 +2466,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(peer_log_alert, 81)
 
-		static constexpr alert_category_t static_category = alert::peer_log_notification;
+		static constexpr alert_category_t static_category = alert_category::peer_log;
 		std::string message() const override;
 
 		// string literal indicating the kind of event. For messages, this is the
@@ -2497,7 +2497,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(lsd_error_alert, 82)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		// The error code
@@ -2562,7 +2562,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_stats_alert, 83)
 
-		static constexpr alert_category_t static_category = alert::stats_notification;
+		static constexpr alert_category_t static_category = alert_category::stats;
 		std::string message() const override;
 
 		// a vector of the currently running DHT lookups.
@@ -2575,7 +2575,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 	// posted every time an incoming request from a peer is accepted and queued
 	// up for being serviced. This alert is only posted if
-	// the alert::incoming_request_notification flag is enabled in the alert
+	// the alert_category::incoming_request flag is enabled in the alert
 	// mask.
 	struct TORRENT_EXPORT incoming_request_alert final : peer_alert
 	{
@@ -2584,7 +2584,7 @@ TORRENT_VERSION_NAMESPACE_2
 			, peer_request r, torrent_handle h
 			, tcp::endpoint const& ep, peer_id const& peer_id);
 
-		static constexpr alert_category_t static_category = alert::incoming_request_notification;
+		static constexpr alert_category_t static_category = alert_category::incoming_request;
 		TORRENT_DEFINE_ALERT(incoming_request_alert, 84)
 
 		std::string message() const override;
@@ -2610,7 +2610,7 @@ TORRENT_VERSION_NAMESPACE_2
 		dht_log_alert(aux::stack_allocator& alloc
 			, dht_module_t m, char const* fmt, va_list v);
 
-		static constexpr alert_category_t static_category = alert::dht_log_notification;
+		static constexpr alert_category_t static_category = alert_category::dht_log;
 		TORRENT_DEFINE_ALERT(dht_log_alert, 85)
 
 		std::string message() const override;
@@ -2627,7 +2627,7 @@ TORRENT_VERSION_NAMESPACE_2
 	};
 
 	// This alert is posted every time a DHT message is sent or received. It is
-	// only posted if the ``alert::dht_log_notification`` alert category is
+	// only posted if the ``alert_category::dht_log`` alert category is
 	// enabled. It contains a verbatim copy of the message.
 	struct TORRENT_EXPORT dht_pkt_alert final : alert
 	{
@@ -2638,7 +2638,7 @@ TORRENT_VERSION_NAMESPACE_2
 		dht_pkt_alert(aux::stack_allocator& alloc, span<char const> buf
 			, dht_pkt_alert::direction_t d, udp::endpoint const& ep);
 
-		static constexpr alert_category_t static_category = alert::dht_log_notification;
+		static constexpr alert_category_t static_category = alert_category::dht_log;
 		TORRENT_DEFINE_ALERT(dht_pkt_alert, 86)
 
 		std::string message() const override;
@@ -2675,7 +2675,7 @@ TORRENT_VERSION_NAMESPACE_2
 			, sha1_hash const& ih
 			, std::vector<tcp::endpoint> const& v);
 
-		static constexpr alert_category_t static_category = alert::dht_operation_notification;
+		static constexpr alert_category_t static_category = alert_category::dht_operation;
 		TORRENT_DEFINE_ALERT(dht_get_peers_reply_alert, 87)
 
 		std::string message() const override;
@@ -2712,7 +2712,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT_PRIO(dht_direct_response_alert, 88, alert_priority_critical)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 		std::string message() const override;
 
 		void const* userdata;
@@ -2745,7 +2745,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(picker_log_alert, 89)
 
-		static constexpr alert_category_t static_category = alert::picker_log_notification;
+		static constexpr alert_category_t static_category = alert_category::picker_log;
 		std::string message() const override;
 
 		static constexpr picker_flags_t partial_ratio = 0_bit;
@@ -2787,7 +2787,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(session_error_alert, 90)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		// The error code, if one is associated with this error
@@ -2810,7 +2810,7 @@ TORRENT_VERSION_NAMESPACE_2
 
 		TORRENT_DEFINE_ALERT(dht_live_nodes_alert, 91)
 
-		static constexpr alert_category_t static_category = alert::dht_notification;
+		static constexpr alert_category_t static_category = alert_category::dht;
 		std::string message() const override;
 
 		// the local DHT node's node-ID this routing table belongs to
@@ -2843,7 +2843,7 @@ TORRENT_VERSION_NAMESPACE_2
 		explicit session_stats_header_alert(aux::stack_allocator& alloc);
 		TORRENT_DEFINE_ALERT(session_stats_header_alert, 92)
 
-		static constexpr alert_category_t static_category = alert::stats_notification;
+		static constexpr alert_category_t static_category = alert_category::stats;
 		std::string message() const override;
 	};
 
@@ -2859,7 +2859,7 @@ TORRENT_VERSION_NAMESPACE_2
 			, std::vector<sha1_hash> const& samples
 			, std::vector<std::pair<sha1_hash, udp::endpoint>> const& nodes);
 
-		static constexpr alert_category_t static_category = alert::dht_operation_notification;
+		static constexpr alert_category_t static_category = alert_category::dht_operation;
 		TORRENT_DEFINE_ALERT(dht_sample_infohashes_alert, 93)
 
 		std::string message() const override;
@@ -2919,7 +2919,7 @@ TORRENT_VERSION_NAMESPACE_2
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #endif
 		static constexpr alert_category_t static_category =
-			alert::upload_notification
+			alert_category::upload
 			PROGRESS_NOTIFICATION
 		;
 #ifdef __GNUC__
@@ -2942,7 +2942,7 @@ TORRENT_VERSION_NAMESPACE_2
 			, std::bitset<num_alert_types> const&);
 		TORRENT_DEFINE_ALERT_PRIO(alerts_dropped_alert, 95, alert_priority_critical + 1)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		// a bitmask indicating which alerts were dropped. Each bit represents the
@@ -2960,7 +2960,7 @@ TORRENT_VERSION_NAMESPACE_2
 			, tcp::endpoint const& ep, operation_t operation, error_code const& ec);
 		TORRENT_DEFINE_ALERT(socks5_alert, 96)
 
-		static constexpr alert_category_t static_category = alert::error_notification;
+		static constexpr alert_category_t static_category = alert_category::error;
 		std::string message() const override;
 
 		// the error
diff --git a/include/libtorrent/session.hpp b/include/libtorrent/session.hpp
index df332f815..d19cb17ae 100644
--- a/include/libtorrent/session.hpp
+++ b/include/libtorrent/session.hpp
@@ -276,7 +276,7 @@ namespace aux {
 		TORRENT_DEPRECATED
 		session(fingerprint const& print
 			, session_flags_t const flags = start_default_features | add_default_plugins
-			, alert_category_t const alert_mask = alert::error_notification)
+			, alert_category_t const alert_mask = alert_category::error)
 		{
 			settings_pack pack;
 			pack.set_int(settings_pack::alert_mask, int(alert_mask));
@@ -297,7 +297,7 @@ namespace aux {
 			, std::pair<int, int> listen_port_range
 			, char const* listen_interface = "0.0.0.0"
 			, session_flags_t const flags = start_default_features | add_default_plugins
-			, alert_category_t const alert_mask = alert::error_notification)
+			, alert_category_t const alert_mask = alert_category::error)
 		{
 			TORRENT_ASSERT(listen_port_range.first > 0);
 			TORRENT_ASSERT(listen_port_range.first <= listen_port_range.second);
diff --git a/include/libtorrent/session_handle.hpp b/include/libtorrent/session_handle.hpp
index b1af3de5d..1b17bf9e5 100644
--- a/include/libtorrent/session_handle.hpp
+++ b/include/libtorrent/session_handle.hpp
@@ -39,7 +39,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/torrent_handle.hpp"
 #include "libtorrent/add_torrent_params.hpp"
 #include "libtorrent/disk_io_thread.hpp" // for cached_piece_info
-#include "libtorrent/alert.hpp" // alert::error_notification
+#include "libtorrent/alert.hpp" // alert_category::error
 #include "libtorrent/peer_class.hpp"
 #include "libtorrent/peer_class_type_filter.hpp"
 #include "libtorrent/peer_id.hpp"
diff --git a/include/libtorrent/settings_pack.hpp b/include/libtorrent/settings_pack.hpp
index 8341673f6..0ddbe7994 100644
--- a/include/libtorrent/settings_pack.hpp
+++ b/include/libtorrent/settings_pack.hpp
@@ -801,9 +801,8 @@ namespace aux {
 			// changes are taken in consideration.
 			enable_ip_notifier,
 
-			// when this is true, nodes whose IDs are derived from their source IP
-			// according to BEP 42 (https://www.bittorrent.org/beps/bep_0042.html) are
-			// preferred in the routing table.
+			// when this is true, nodes whose IDs are derived from their source
+			// IP according to `BEP 42`_ are preferred in the routing table.
 			dht_prefer_verified_node_ids,
 
 			// when this is true, create an affinity for downloading 4 MiB extents
@@ -1650,7 +1649,7 @@ namespace aux {
 			// retry a failed port bind
 			max_retry_port_bind,
 
-			// a bitmask combining flags from alert::category_t defining which
+			// a bitmask combining flags from alert_category_t defining which
 			// kinds of alerts to receive
 			alert_mask,
 
diff --git a/simulation/test_auto_manage.cpp b/simulation/test_auto_manage.cpp
index 706411691..e6e0ba114 100644
--- a/simulation/test_auto_manage.cpp
+++ b/simulation/test_auto_manage.cpp
@@ -656,7 +656,7 @@ TORRENT_TEST(resume_reject_when_paused)
 {
 	run_test(
 		[](settings_pack& sett) {
-			sett.set_int(settings_pack::alert_mask, alert::all_categories);
+			sett.set_int(settings_pack::alert_mask, alert_category::all);
 		},
 
 		[](lt::session& ses) {
@@ -729,7 +729,7 @@ TORRENT_TEST(no_resume_when_paused)
 {
 	run_test(
 		[](settings_pack& sett) {
-			sett.set_int(settings_pack::alert_mask, alert::all_categories);
+			sett.set_int(settings_pack::alert_mask, alert_category::all);
 		},
 
 		[](lt::session& ses) {
@@ -797,7 +797,7 @@ TORRENT_TEST(no_resume_when_started)
 {
 	run_test(
 		[](settings_pack& sett) {
-			sett.set_int(settings_pack::alert_mask, alert::all_categories);
+			sett.set_int(settings_pack::alert_mask, alert_category::all);
 		},
 
 		[](lt::session& ses) {
diff --git a/simulation/test_dht.cpp b/simulation/test_dht.cpp
index 72ad11a8c..c9c285859 100644
--- a/simulation/test_dht.cpp
+++ b/simulation/test_dht.cpp
@@ -90,7 +90,7 @@ void bootstrap_session(std::vector<dht_network*> networks, lt::session& ses)
 	ses.load_state(e);
 	lt::settings_pack pack;
 	pack.set_bool(lt::settings_pack::enable_dht, true);
-	pack.set_int(lt::settings_pack::alert_mask, lt::alert::all_categories);
+	pack.set_int(lt::settings_pack::alert_mask, lt::alert_category::all);
 	ses.apply_settings(pack);
 }
 #endif // TORRENT_DISABLE_DHT
diff --git a/simulation/test_session.cpp b/simulation/test_session.cpp
index d53c47b74..c0322ce33 100644
--- a/simulation/test_session.cpp
+++ b/simulation/test_session.cpp
@@ -78,7 +78,7 @@ TORRENT_TEST(ip_notifier_setting)
 		, [](lt::settings_pack& pack)
 		{
 			pack.set_int(settings_pack::tick_interval, 1000);
-			pack.set_int(settings_pack::alert_mask, alert::all_categories);
+			pack.set_int(settings_pack::alert_mask, alert_category::all);
 		}
 		// add torrent
 		, [](lt::add_torrent_params&) {}
@@ -146,7 +146,7 @@ TORRENT_TEST(add_extension_while_transfer)
 		, [](lt::settings_pack& pack)
 		{
 			pack.set_int(settings_pack::tick_interval, 1000);
-			pack.set_int(settings_pack::alert_mask, alert::all_categories);
+			pack.set_int(settings_pack::alert_mask, alert_category::all);
 		}
 		// add torrent
 		, [](lt::add_torrent_params&) {}
@@ -191,9 +191,9 @@ TORRENT_TEST(tie_listen_ports)
 	// create session
 	auto pack = settings();
 	pack.set_str(settings_pack::listen_interfaces, "0.0.0.0:0");
-	pack.set_int(settings_pack::alert_mask, alert::error_notification
-		| alert::status_notification
-		| alert::torrent_log_notification);
+	pack.set_int(settings_pack::alert_mask, alert_category::error
+		| alert_category::status
+		| alert_category::torrent_log);
 
 	auto ses = std::make_shared<lt::session>(pack, ios);
 
diff --git a/simulation/test_swarm.cpp b/simulation/test_swarm.cpp
index f581feb78..a142198f2 100644
--- a/simulation/test_swarm.cpp
+++ b/simulation/test_swarm.cpp
@@ -587,7 +587,7 @@ TORRENT_TEST(torrent_completed_alert)
 		// add session
 		, [](lt::settings_pack& pack)
 		{
-			pack.set_int(lt::settings_pack::alert_mask, alert::file_progress_notification);
+			pack.set_int(lt::settings_pack::alert_mask, alert_category::file_progress);
 		}
 		// add torrent
 		, [](lt::add_torrent_params&) {}
@@ -625,7 +625,7 @@ TORRENT_TEST(block_uploaded_alert)
 		, [](lt::settings_pack& pack)
 		{
 			pack.set_int(lt::settings_pack::alert_mask,
-				alert::upload_notification | alert::status_notification);
+				alert_category::upload | alert_category::status);
 		}
 		// add torrent
 		, [](lt::add_torrent_params&) {}
diff --git a/simulation/test_torrent_status.cpp b/simulation/test_torrent_status.cpp
index 8c0b6be88..ab81c9dd2 100644
--- a/simulation/test_torrent_status.cpp
+++ b/simulation/test_torrent_status.cpp
@@ -388,7 +388,7 @@ TORRENT_TEST(alert_order)
 	setup_swarm(1, swarm_test::upload
 		// add session
 		, [](lt::settings_pack& sett) {
-			sett.set_int(settings_pack::alert_mask, alert::all_categories);
+			sett.set_int(settings_pack::alert_mask, alert_category::all);
 		}
 		// add torrent
 		, [](lt::add_torrent_params ) {}
diff --git a/simulation/test_tracker.cpp b/simulation/test_tracker.cpp
index e82d26254..ed87de636 100644
--- a/simulation/test_tracker.cpp
+++ b/simulation/test_tracker.cpp
@@ -1305,9 +1305,9 @@ void test_tracker_tiers(lt::settings_pack pack
 {
 	using namespace libtorrent;
 
-	pack.set_int(settings_pack::alert_mask, alert::error_notification
-		| alert::status_notification
-		| alert::torrent_log_notification);
+	pack.set_int(settings_pack::alert_mask, alert_category::error
+		| alert_category::status
+		| alert_category::torrent_log);
 
 	// setup the simulation
 	struct sim_config : sim::default_config
diff --git a/src/session_handle.cpp b/src/session_handle.cpp
index e315edd8f..478ac5e78 100644
--- a/src/session_handle.cpp
+++ b/src/session_handle.cpp
@@ -1182,14 +1182,14 @@ namespace {
 		alert_category_t m = {};
 		switch (s)
 		{
-			case alert::debug: m = alert::all_categories; break;
-			case alert::info: m = alert::all_categories & ~(alert::debug_notification
-				| alert::progress_notification | alert::dht_notification); break;
-			case alert::warning: m = alert::all_categories & ~(alert::debug_notification
-				| alert::status_notification | alert::progress_notification
-				| alert::dht_notification); break;
-			case alert::critical: m = alert::error_notification | alert::storage_notification; break;
-			case alert::fatal: m = alert::error_notification; break;
+			case alert::debug: m = alert_category::all; break;
+			case alert::info: m = alert_category::all & ~(alert::debug_notification
+				| alert::progress_notification | alert_category::dht); break;
+			case alert::warning: m = alert_category::all & ~(alert::debug_notification
+				| alert_category::status | alert::progress_notification
+				| alert_category::dht); break;
+			case alert::critical: m = alert_category::error | alert_category::storage; break;
+			case alert::fatal: m = alert_category::error; break;
 			case alert::none: m = {}; break;
 		}
 
diff --git a/src/settings_pack.cpp b/src/settings_pack.cpp
index 15d9c8e42..b2dc63d83 100644
--- a/src/settings_pack.cpp
+++ b/src/settings_pack.cpp
@@ -333,7 +333,7 @@ constexpr int CLOSE_FILE_INTERVAL = 0;
 		SET(connect_seed_every_n_download, 10, nullptr),
 		SET(max_http_recv_buffer_size, 4*1024*204, nullptr),
 		SET(max_retry_port_bind, 10, nullptr),
-		SET(alert_mask, int(static_cast<std::uint32_t>(alert::error_notification)), &session_impl::update_alert_mask),
+		SET(alert_mask, int(static_cast<std::uint32_t>(alert_category::error)), &session_impl::update_alert_mask),
 		SET(out_enc_policy, settings_pack::pe_enabled, nullptr),
 		SET(in_enc_policy, settings_pack::pe_enabled, nullptr),
 		SET(allowed_enc_level, settings_pack::pe_both, nullptr),
diff --git a/test/settings.cpp b/test/settings.cpp
index 9082c456d..01f5d2250 100644
--- a/test/settings.cpp
+++ b/test/settings.cpp
@@ -39,24 +39,24 @@ using namespace lt;
 lt::settings_pack settings()
 {
 	alert_category_t const mask =
-		alert::error_notification
-		| alert::peer_notification
-		| alert::port_mapping_notification
-		| alert::storage_notification
-		| alert::tracker_notification
-		| alert::connect_notification
-		| alert::status_notification
-		| alert::ip_block_notification
-		| alert::dht_notification
-		| alert::session_log_notification
-		| alert::torrent_log_notification
-		| alert::peer_log_notification
-		| alert::incoming_request_notification
-		| alert::dht_log_notification
-		| alert::dht_operation_notification
-		| alert::port_mapping_log_notification
-		| alert::file_progress_notification
-		| alert::piece_progress_notification;
+		alert_category::error
+		| alert_category::peer
+		| alert_category::port_mapping
+		| alert_category::storage
+		| alert_category::tracker
+		| alert_category::connect
+		| alert_category::status
+		| alert_category::ip_block
+		| alert_category::dht
+		| alert_category::session_log
+		| alert_category::torrent_log
+		| alert_category::peer_log
+		| alert_category::incoming_request
+		| alert_category::dht_log
+		| alert_category::dht_operation
+		| alert_category::port_mapping_log
+		| alert_category::file_progress
+		| alert_category::piece_progress;
 
 	settings_pack pack;
 	pack.set_bool(settings_pack::enable_lsd, false);
diff --git a/test/test_alert_manager.cpp b/test/test_alert_manager.cpp
index 48ec63ab5..5277dba02 100644
--- a/test/test_alert_manager.cpp
+++ b/test/test_alert_manager.cpp
@@ -44,7 +44,7 @@ using namespace lt;
 
 TORRENT_TEST(limit)
 {
-	alert_manager mgr(500, alert::all_categories);
+	alert_manager mgr(500, alert_category::all);
 
 	TEST_EQUAL(mgr.alert_queue_size_limit(), 500);
 	TEST_EQUAL(mgr.pending(), false);
@@ -83,7 +83,7 @@ TORRENT_TEST(limit)
 TORRENT_TEST(limit_int_max)
 {
 	int const inf = std::numeric_limits<int>::max();
-	alert_manager mgr(inf, alert::all_categories);
+	alert_manager mgr(inf, alert_category::all);
 
 	TEST_EQUAL(mgr.alert_queue_size_limit(), inf);
 
@@ -101,7 +101,7 @@ TORRENT_TEST(limit_int_max)
 
 TORRENT_TEST(priority_limit)
 {
-	alert_manager mgr(100, alert::all_categories);
+	alert_manager mgr(100, alert_category::all);
 
 	TEST_EQUAL(mgr.alert_queue_size_limit(), 100);
 
@@ -132,7 +132,7 @@ void test_notify_fun(int& cnt)
 TORRENT_TEST(notify_function)
 {
 	int cnt = 0;
-	alert_manager mgr(100, alert::all_categories);
+	alert_manager mgr(100, alert_category::all);
 
 	TEST_EQUAL(mgr.alert_queue_size_limit(), 100);
 	TEST_EQUAL(mgr.pending(), false);
@@ -191,7 +191,7 @@ TORRENT_TEST(extensions)
 {
 #ifndef TORRENT_DISABLE_EXTENSIONS
 	memset(plugin_alerts, 0, sizeof(plugin_alerts));
-	alert_manager mgr(100, alert::all_categories);
+	alert_manager mgr(100, alert_category::all);
 
 	mgr.add_extension(std::make_shared<test_plugin>(0));
 	mgr.add_extension(std::make_shared<test_plugin>(1));
@@ -228,7 +228,7 @@ void post_torrent_added(alert_manager* mgr)
 
 TORRENT_TEST(wait_for_alert)
 {
-	alert_manager mgr(100, alert::all_categories);
+	alert_manager mgr(100, alert_category::all);
 
 	time_point start = clock_type::now();
 
@@ -270,7 +270,7 @@ TORRENT_TEST(wait_for_alert)
 
 TORRENT_TEST(alert_mask)
 {
-	alert_manager mgr(100, alert::all_categories);
+	alert_manager mgr(100, alert_category::all);
 
 	TEST_CHECK(mgr.should_post<add_torrent_alert>());
 	TEST_CHECK(mgr.should_post<torrent_paused_alert>());
@@ -283,7 +283,7 @@ TORRENT_TEST(alert_mask)
 
 TORRENT_TEST(dropped_alerts)
 {
-	alert_manager mgr(1, alert::all_categories);
+	alert_manager mgr(1, alert_category::all);
 
 	// nothing has dropped yet
 	mgr.emplace_alert<torrent_finished_alert>(torrent_handle());
@@ -302,7 +302,7 @@ TORRENT_TEST(dropped_alerts)
 
 TORRENT_TEST(alerts_dropped_alert)
 {
-	alert_manager mgr(1, alert::all_categories);
+	alert_manager mgr(1, alert_category::all);
 
 	mgr.emplace_alert<torrent_finished_alert>(torrent_handle());
 	mgr.emplace_alert<torrent_finished_alert>(torrent_handle());
@@ -333,7 +333,7 @@ struct post_plugin : lt::plugin
 // plugin handler
 TORRENT_TEST(recursive_alerts)
 {
-	alert_manager mgr(100, alert::all_categories);
+	alert_manager mgr(100, alert_category::all);
 	auto pl = std::make_shared<post_plugin>(mgr);
 	mgr.add_extension(pl);
 
diff --git a/test/test_alert_types.cpp b/test/test_alert_types.cpp
index ecffb14a1..f427b219f 100644
--- a/test/test_alert_types.cpp
+++ b/test/test_alert_types.cpp
@@ -51,7 +51,7 @@ TORRENT_TEST(alerts_types)
 	TEST_EQUAL(torrent_alert::alert_type, 0);
 	TEST_EQUAL(peer_alert::alert_type, 1);
 	TEST_EQUAL(tracker_alert::alert_type, 2);
-	TEST_EQUAL(alert::debug_notification, alert::connect_notification);
+	TEST_EQUAL(alert::debug_notification, alert_category::connect);
 #endif
 
 #define TEST_ALERT_TYPE(name, seq, prio, cat) \
@@ -63,7 +63,7 @@ TORRENT_TEST(alerts_types)
 	count_alert_types++
 
 #if TORRENT_ABI_VERSION == 1
-	TEST_ALERT_TYPE(torrent_added_alert, 3, 0, alert::status_notification);
+	TEST_ALERT_TYPE(torrent_added_alert, 3, 0, alert_category::status);
 #else
 	++count_alert_types;
 #endif
@@ -74,111 +74,111 @@ TORRENT_TEST(alerts_types)
 #define PROGRESS_NOTIFICATION
 #endif
 
-	TEST_ALERT_TYPE(torrent_removed_alert, 4, 2, alert::status_notification);
-	TEST_ALERT_TYPE(read_piece_alert, 5, 2, alert::storage_notification);
-	TEST_ALERT_TYPE(file_completed_alert, 6, 0, PROGRESS_NOTIFICATION alert::file_progress_notification);
-	TEST_ALERT_TYPE(file_renamed_alert, 7, 2, alert::storage_notification);
-	TEST_ALERT_TYPE(file_rename_failed_alert, 8, 2, alert::storage_notification);
-	TEST_ALERT_TYPE(performance_alert, 9, 0, alert::performance_warning);
-	TEST_ALERT_TYPE(state_changed_alert, 10, 1, alert::status_notification);
-	TEST_ALERT_TYPE(tracker_error_alert, 11, 1, alert::tracker_notification | alert::error_notification);
-	TEST_ALERT_TYPE(tracker_warning_alert, 12, 0, alert::tracker_notification | alert::error_notification);
-	TEST_ALERT_TYPE(scrape_reply_alert, 13, 2, alert::tracker_notification);
-	TEST_ALERT_TYPE(scrape_failed_alert, 14, 2, alert::tracker_notification | alert::error_notification);
-	TEST_ALERT_TYPE(tracker_reply_alert, 15, 0, alert::tracker_notification);
-	TEST_ALERT_TYPE(dht_reply_alert, 16, 0, alert::dht_notification | alert::tracker_notification);
-	TEST_ALERT_TYPE(tracker_announce_alert, 17, 0, alert::tracker_notification);
-	TEST_ALERT_TYPE(hash_failed_alert, 18, 0, alert::status_notification);
-	TEST_ALERT_TYPE(peer_ban_alert, 19, 0, alert::peer_notification);
-	TEST_ALERT_TYPE(peer_unsnubbed_alert, 20, 0, alert::peer_notification);
-	TEST_ALERT_TYPE(peer_snubbed_alert, 21, 0, alert::peer_notification);
-	TEST_ALERT_TYPE(peer_error_alert, 22, 0, alert::peer_notification);
-	TEST_ALERT_TYPE(peer_connect_alert, 23, 0, alert::connect_notification);
-	TEST_ALERT_TYPE(peer_disconnected_alert, 24, 0, alert::connect_notification);
-	TEST_ALERT_TYPE(invalid_request_alert, 25, 0, alert::peer_notification);
-	TEST_ALERT_TYPE(torrent_finished_alert, 26, 1, alert::status_notification);
-	TEST_ALERT_TYPE(piece_finished_alert, 27, 0, PROGRESS_NOTIFICATION alert::piece_progress_notification);
-	TEST_ALERT_TYPE(request_dropped_alert, 28, 0, PROGRESS_NOTIFICATION alert::block_progress_notification | alert::peer_notification);
-	TEST_ALERT_TYPE(block_timeout_alert, 29, 0, PROGRESS_NOTIFICATION alert::block_progress_notification | alert::peer_notification);
-	TEST_ALERT_TYPE(block_finished_alert, 30, 0, PROGRESS_NOTIFICATION alert::block_progress_notification);
-	TEST_ALERT_TYPE(block_downloading_alert, 31, 0, PROGRESS_NOTIFICATION alert::block_progress_notification);
-	TEST_ALERT_TYPE(unwanted_block_alert, 32, 0, alert::peer_notification);
-	TEST_ALERT_TYPE(storage_moved_alert, 33, 2, alert::storage_notification);
-	TEST_ALERT_TYPE(storage_moved_failed_alert, 34, 2, alert::storage_notification);
-	TEST_ALERT_TYPE(torrent_deleted_alert, 35, 2, alert::storage_notification);
-	TEST_ALERT_TYPE(torrent_delete_failed_alert, 36, 2, alert::storage_notification | alert::error_notification);
-	TEST_ALERT_TYPE(save_resume_data_alert, 37, 2, alert::storage_notification);
-	TEST_ALERT_TYPE(save_resume_data_failed_alert, 38, 2, alert::storage_notification | alert::error_notification);
-	TEST_ALERT_TYPE(torrent_paused_alert, 39, 1, alert::status_notification);
-	TEST_ALERT_TYPE(torrent_resumed_alert, 40, 1, alert::status_notification);
-	TEST_ALERT_TYPE(torrent_checked_alert, 41, 1, alert::status_notification);
-	TEST_ALERT_TYPE(url_seed_alert, 42, 0, alert::peer_notification | alert::error_notification);
-	TEST_ALERT_TYPE(file_error_alert, 43, 1, alert::status_notification | alert::error_notification | alert::storage_notification);
-	TEST_ALERT_TYPE(metadata_failed_alert, 44, 0, alert::error_notification);
-	TEST_ALERT_TYPE(metadata_received_alert, 45, 0, alert::status_notification);
-	TEST_ALERT_TYPE(udp_error_alert, 46, 0, alert::error_notification);
-	TEST_ALERT_TYPE(external_ip_alert, 47, 0, alert::status_notification);
-	TEST_ALERT_TYPE(listen_failed_alert, 48, 2, alert::status_notification | alert::error_notification);
-	TEST_ALERT_TYPE(listen_succeeded_alert, 49, 2, alert::status_notification);
-	TEST_ALERT_TYPE(portmap_error_alert, 50, 0, alert::port_mapping_notification | alert::error_notification);
-	TEST_ALERT_TYPE(portmap_alert, 51, 0, alert::port_mapping_notification);
-	TEST_ALERT_TYPE(portmap_log_alert, 52, 0, alert::port_mapping_log_notification);
-	TEST_ALERT_TYPE(fastresume_rejected_alert, 53, 2, alert::status_notification | alert::error_notification);
-	TEST_ALERT_TYPE(peer_blocked_alert, 54, 0, alert::ip_block_notification);
-	TEST_ALERT_TYPE(dht_announce_alert, 55, 0, alert::dht_notification);
-	TEST_ALERT_TYPE(dht_get_peers_alert, 56, 0, alert::dht_notification);
-	TEST_ALERT_TYPE(stats_alert, 57, 0, alert::stats_notification);
-	TEST_ALERT_TYPE(cache_flushed_alert, 58, 1, alert::storage_notification);
+	TEST_ALERT_TYPE(torrent_removed_alert, 4, 2, alert_category::status);
+	TEST_ALERT_TYPE(read_piece_alert, 5, 2, alert_category::storage);
+	TEST_ALERT_TYPE(file_completed_alert, 6, 0, PROGRESS_NOTIFICATION alert_category::file_progress);
+	TEST_ALERT_TYPE(file_renamed_alert, 7, 2, alert_category::storage);
+	TEST_ALERT_TYPE(file_rename_failed_alert, 8, 2, alert_category::storage);
+	TEST_ALERT_TYPE(performance_alert, 9, 0, alert_category::performance_warning);
+	TEST_ALERT_TYPE(state_changed_alert, 10, 1, alert_category::status);
+	TEST_ALERT_TYPE(tracker_error_alert, 11, 1, alert_category::tracker | alert_category::error);
+	TEST_ALERT_TYPE(tracker_warning_alert, 12, 0, alert_category::tracker | alert_category::error);
+	TEST_ALERT_TYPE(scrape_reply_alert, 13, 2, alert_category::tracker);
+	TEST_ALERT_TYPE(scrape_failed_alert, 14, 2, alert_category::tracker | alert_category::error);
+	TEST_ALERT_TYPE(tracker_reply_alert, 15, 0, alert_category::tracker);
+	TEST_ALERT_TYPE(dht_reply_alert, 16, 0, alert_category::dht | alert_category::tracker);
+	TEST_ALERT_TYPE(tracker_announce_alert, 17, 0, alert_category::tracker);
+	TEST_ALERT_TYPE(hash_failed_alert, 18, 0, alert_category::status);
+	TEST_ALERT_TYPE(peer_ban_alert, 19, 0, alert_category::peer);
+	TEST_ALERT_TYPE(peer_unsnubbed_alert, 20, 0, alert_category::peer);
+	TEST_ALERT_TYPE(peer_snubbed_alert, 21, 0, alert_category::peer);
+	TEST_ALERT_TYPE(peer_error_alert, 22, 0, alert_category::peer);
+	TEST_ALERT_TYPE(peer_connect_alert, 23, 0, alert_category::connect);
+	TEST_ALERT_TYPE(peer_disconnected_alert, 24, 0, alert_category::connect);
+	TEST_ALERT_TYPE(invalid_request_alert, 25, 0, alert_category::peer);
+	TEST_ALERT_TYPE(torrent_finished_alert, 26, 1, alert_category::status);
+	TEST_ALERT_TYPE(piece_finished_alert, 27, 0, PROGRESS_NOTIFICATION alert_category::piece_progress);
+	TEST_ALERT_TYPE(request_dropped_alert, 28, 0, PROGRESS_NOTIFICATION alert_category::block_progress | alert_category::peer);
+	TEST_ALERT_TYPE(block_timeout_alert, 29, 0, PROGRESS_NOTIFICATION alert_category::block_progress | alert_category::peer);
+	TEST_ALERT_TYPE(block_finished_alert, 30, 0, PROGRESS_NOTIFICATION alert_category::block_progress);
+	TEST_ALERT_TYPE(block_downloading_alert, 31, 0, PROGRESS_NOTIFICATION alert_category::block_progress);
+	TEST_ALERT_TYPE(unwanted_block_alert, 32, 0, alert_category::peer);
+	TEST_ALERT_TYPE(storage_moved_alert, 33, 2, alert_category::storage);
+	TEST_ALERT_TYPE(storage_moved_failed_alert, 34, 2, alert_category::storage);
+	TEST_ALERT_TYPE(torrent_deleted_alert, 35, 2, alert_category::storage);
+	TEST_ALERT_TYPE(torrent_delete_failed_alert, 36, 2, alert_category::storage | alert_category::error);
+	TEST_ALERT_TYPE(save_resume_data_alert, 37, 2, alert_category::storage);
+	TEST_ALERT_TYPE(save_resume_data_failed_alert, 38, 2, alert_category::storage | alert_category::error);
+	TEST_ALERT_TYPE(torrent_paused_alert, 39, 1, alert_category::status);
+	TEST_ALERT_TYPE(torrent_resumed_alert, 40, 1, alert_category::status);
+	TEST_ALERT_TYPE(torrent_checked_alert, 41, 1, alert_category::status);
+	TEST_ALERT_TYPE(url_seed_alert, 42, 0, alert_category::peer | alert_category::error);
+	TEST_ALERT_TYPE(file_error_alert, 43, 1, alert_category::status | alert_category::error | alert_category::storage);
+	TEST_ALERT_TYPE(metadata_failed_alert, 44, 0, alert_category::error);
+	TEST_ALERT_TYPE(metadata_received_alert, 45, 0, alert_category::status);
+	TEST_ALERT_TYPE(udp_error_alert, 46, 0, alert_category::error);
+	TEST_ALERT_TYPE(external_ip_alert, 47, 0, alert_category::status);
+	TEST_ALERT_TYPE(listen_failed_alert, 48, 2, alert_category::status | alert_category::error);
+	TEST_ALERT_TYPE(listen_succeeded_alert, 49, 2, alert_category::status);
+	TEST_ALERT_TYPE(portmap_error_alert, 50, 0, alert_category::port_mapping | alert_category::error);
+	TEST_ALERT_TYPE(portmap_alert, 51, 0, alert_category::port_mapping);
+	TEST_ALERT_TYPE(portmap_log_alert, 52, 0, alert_category::port_mapping_log);
+	TEST_ALERT_TYPE(fastresume_rejected_alert, 53, 2, alert_category::status | alert_category::error);
+	TEST_ALERT_TYPE(peer_blocked_alert, 54, 0, alert_category::ip_block);
+	TEST_ALERT_TYPE(dht_announce_alert, 55, 0, alert_category::dht);
+	TEST_ALERT_TYPE(dht_get_peers_alert, 56, 0, alert_category::dht);
+	TEST_ALERT_TYPE(stats_alert, 57, 0, alert_category::stats);
+	TEST_ALERT_TYPE(cache_flushed_alert, 58, 1, alert_category::storage);
 #if TORRENT_ABI_VERSION == 1
-	TEST_ALERT_TYPE(anonymous_mode_alert, 59, 0, alert::error_notification);
+	TEST_ALERT_TYPE(anonymous_mode_alert, 59, 0, alert_category::error);
 #else
 	count_alert_types++;
 #endif
-	TEST_ALERT_TYPE(lsd_peer_alert, 60, 0, alert::peer_notification);
-	TEST_ALERT_TYPE(trackerid_alert, 61, 0, alert::status_notification);
-	TEST_ALERT_TYPE(dht_bootstrap_alert, 62, 0, alert::dht_notification);
+	TEST_ALERT_TYPE(lsd_peer_alert, 60, 0, alert_category::peer);
+	TEST_ALERT_TYPE(trackerid_alert, 61, 0, alert_category::status);
+	TEST_ALERT_TYPE(dht_bootstrap_alert, 62, 0, alert_category::dht);
 	count_alert_types++; // 63 is gone
-	TEST_ALERT_TYPE(torrent_error_alert, 64, 1, alert::error_notification | alert::status_notification);
-	TEST_ALERT_TYPE(torrent_need_cert_alert, 65, 2, alert::status_notification);
-	TEST_ALERT_TYPE(incoming_connection_alert, 66, 0, alert::peer_notification);
-	TEST_ALERT_TYPE(add_torrent_alert, 67, 2, alert::status_notification);
-	TEST_ALERT_TYPE(state_update_alert, 68, 1, alert::status_notification);
+	TEST_ALERT_TYPE(torrent_error_alert, 64, 1, alert_category::error | alert_category::status);
+	TEST_ALERT_TYPE(torrent_need_cert_alert, 65, 2, alert_category::status);
+	TEST_ALERT_TYPE(incoming_connection_alert, 66, 0, alert_category::peer);
+	TEST_ALERT_TYPE(add_torrent_alert, 67, 2, alert_category::status);
+	TEST_ALERT_TYPE(state_update_alert, 68, 1, alert_category::status);
 #if TORRENT_ABI_VERSION == 1
-	TEST_ALERT_TYPE(mmap_cache_alert, 69, 0, alert::error_notification);
+	TEST_ALERT_TYPE(mmap_cache_alert, 69, 0, alert_category::error);
 #else
 	count_alert_types++;
 #endif
-	TEST_ALERT_TYPE(session_stats_alert, 70, 2, alert::stats_notification);
+	TEST_ALERT_TYPE(session_stats_alert, 70, 2, alert_category::stats);
 #if TORRENT_ABI_VERSION == 1
-	TEST_ALERT_TYPE(torrent_update_alert, 71, 2, alert::status_notification);
+	TEST_ALERT_TYPE(torrent_update_alert, 71, 2, alert_category::status);
 #else
 	count_alert_types++;
 #endif
 	count_alert_types++; // 72 is gone
-	TEST_ALERT_TYPE(dht_error_alert, 73, 0, alert::error_notification | alert::dht_notification);
-	TEST_ALERT_TYPE(dht_immutable_item_alert, 74, 2, alert::dht_notification);
-	TEST_ALERT_TYPE(dht_mutable_item_alert, 75, 2, alert::dht_notification);
-	TEST_ALERT_TYPE(dht_put_alert, 76, 0, alert::dht_notification);
-	TEST_ALERT_TYPE(i2p_alert, 77, 0, alert::error_notification);
-	TEST_ALERT_TYPE(dht_outgoing_get_peers_alert, 78, 0, alert::dht_notification);
-	TEST_ALERT_TYPE(log_alert, 79, 0, alert::session_log_notification);
-	TEST_ALERT_TYPE(torrent_log_alert, 80, 0, alert::torrent_log_notification);
-	TEST_ALERT_TYPE(peer_log_alert, 81, 0, alert::peer_log_notification);
-	TEST_ALERT_TYPE(lsd_error_alert, 82, 0, alert::error_notification);
-	TEST_ALERT_TYPE(dht_stats_alert, 83, 0, alert::stats_notification);
-	TEST_ALERT_TYPE(incoming_request_alert, 84, 0, alert::incoming_request_notification);
-	TEST_ALERT_TYPE(dht_log_alert, 85, 0, alert::dht_log_notification);
-	TEST_ALERT_TYPE(dht_pkt_alert, 86, 0, alert::dht_log_notification);
-	TEST_ALERT_TYPE(dht_get_peers_reply_alert, 87, 0, alert::dht_operation_notification);
-	TEST_ALERT_TYPE(dht_direct_response_alert, 88, 2, alert::dht_notification);
-	TEST_ALERT_TYPE(picker_log_alert, 89, 0, alert::picker_log_notification);
-	TEST_ALERT_TYPE(session_error_alert, 90, 0, alert::error_notification);
-	TEST_ALERT_TYPE(dht_live_nodes_alert, 91, 0, alert::dht_notification);
-	TEST_ALERT_TYPE(session_stats_header_alert, 92, 0, alert::stats_notification);
-	TEST_ALERT_TYPE(dht_sample_infohashes_alert, 93, 0, alert::dht_operation_notification);
-	TEST_ALERT_TYPE(block_uploaded_alert, 94, 0, PROGRESS_NOTIFICATION alert::upload_notification);
-	TEST_ALERT_TYPE(alerts_dropped_alert, 95, 3, alert::error_notification);
-	TEST_ALERT_TYPE(socks5_alert, 96, 0, alert::error_notification);
+	TEST_ALERT_TYPE(dht_error_alert, 73, 0, alert_category::error | alert_category::dht);
+	TEST_ALERT_TYPE(dht_immutable_item_alert, 74, 2, alert_category::dht);
+	TEST_ALERT_TYPE(dht_mutable_item_alert, 75, 2, alert_category::dht);
+	TEST_ALERT_TYPE(dht_put_alert, 76, 0, alert_category::dht);
+	TEST_ALERT_TYPE(i2p_alert, 77, 0, alert_category::error);
+	TEST_ALERT_TYPE(dht_outgoing_get_peers_alert, 78, 0, alert_category::dht);
+	TEST_ALERT_TYPE(log_alert, 79, 0, alert_category::session_log);
+	TEST_ALERT_TYPE(torrent_log_alert, 80, 0, alert_category::torrent_log);
+	TEST_ALERT_TYPE(peer_log_alert, 81, 0, alert_category::peer_log);
+	TEST_ALERT_TYPE(lsd_error_alert, 82, 0, alert_category::error);
+	TEST_ALERT_TYPE(dht_stats_alert, 83, 0, alert_category::stats);
+	TEST_ALERT_TYPE(incoming_request_alert, 84, 0, alert_category::incoming_request);
+	TEST_ALERT_TYPE(dht_log_alert, 85, 0, alert_category::dht_log);
+	TEST_ALERT_TYPE(dht_pkt_alert, 86, 0, alert_category::dht_log);
+	TEST_ALERT_TYPE(dht_get_peers_reply_alert, 87, 0, alert_category::dht_operation);
+	TEST_ALERT_TYPE(dht_direct_response_alert, 88, 2, alert_category::dht);
+	TEST_ALERT_TYPE(picker_log_alert, 89, 0, alert_category::picker_log);
+	TEST_ALERT_TYPE(session_error_alert, 90, 0, alert_category::error);
+	TEST_ALERT_TYPE(dht_live_nodes_alert, 91, 0, alert_category::dht);
+	TEST_ALERT_TYPE(session_stats_header_alert, 92, 0, alert_category::stats);
+	TEST_ALERT_TYPE(dht_sample_infohashes_alert, 93, 0, alert_category::dht_operation);
+	TEST_ALERT_TYPE(block_uploaded_alert, 94, 0, PROGRESS_NOTIFICATION alert_category::upload);
+	TEST_ALERT_TYPE(alerts_dropped_alert, 95, 3, alert_category::error);
+	TEST_ALERT_TYPE(socks5_alert, 96, 0, alert_category::error);
 
 #undef TEST_ALERT_TYPE
 
@@ -254,7 +254,7 @@ TORRENT_TEST(dht_live_nodes_alert)
 
 TORRENT_TEST(session_stats_alert)
 {
-	alert_manager mgr(1, alert::stats_notification);
+	alert_manager mgr(1, alert_category::stats);
 
 	std::vector<alert*> alerts;
 	counters cnt;
diff --git a/test/test_lsd.cpp b/test/test_lsd.cpp
index 8bd96b2bc..18444e2aa 100644
--- a/test/test_lsd.cpp
+++ b/test/test_lsd.cpp
@@ -53,12 +53,12 @@ void test_lsd()
 	session_proxy p2;
 
 	settings_pack pack;
-	pack.set_int(settings_pack::alert_mask, alert::error_notification
-		| alert::session_log_notification
-		| alert::torrent_log_notification
-		| alert::peer_log_notification
-		| alert::ip_block_notification
-		| alert::status_notification);
+	pack.set_int(settings_pack::alert_mask, alert_category::error
+		| alert_category::session_log
+		| alert_category::torrent_log
+		| alert_category::peer_log
+		| alert_category::ip_block
+		| alert_category::status);
 	pack.set_bool(settings_pack::enable_dht, false);
 	pack.set_bool(settings_pack::enable_lsd, true);
 	pack.set_bool(settings_pack::enable_upnp, false);
diff --git a/test/test_remap_files.cpp b/test/test_remap_files.cpp
index 8dbfb55cb..f653670ed 100644
--- a/test/test_remap_files.cpp
+++ b/test/test_remap_files.cpp
@@ -72,8 +72,8 @@ void test_remap_files(storage_mode_t storage_mode = storage_mode_sparse)
 
 	t->remap_files(fs);
 
-	auto const alert_mask = alert::all_categories
-		& ~alert::stats_notification;
+	auto const alert_mask = alert_category::all
+		& ~alert_category::stats;
 
 	session_proxy p1;
 
diff --git a/test/test_session.cpp b/test/test_session.cpp
index ed24eb17e..a84640c14 100644
--- a/test/test_session.cpp
+++ b/test/test_session.cpp
@@ -460,7 +460,7 @@ TORRENT_TEST(init_dht_default_bootstrap)
 {
 	settings_pack p = settings();
 	p.set_bool(settings_pack::enable_dht, true);
-	p.set_int(settings_pack::alert_mask, alert::all_categories);
+	p.set_int(settings_pack::alert_mask, alert_category::all);
 	// default value
 	p.set_str(settings_pack::dht_bootstrap_nodes, "dht.libtorrent.org:25401");
 
@@ -474,7 +474,7 @@ TORRENT_TEST(init_dht_invalid_bootstrap)
 {
 	settings_pack p = settings();
 	p.set_bool(settings_pack::enable_dht, true);
-	p.set_int(settings_pack::alert_mask, alert::all_categories);
+	p.set_int(settings_pack::alert_mask, alert_category::all);
 	// no default value
 	p.set_str(settings_pack::dht_bootstrap_nodes, "test.libtorrent.org:25401:8888");
 
@@ -488,7 +488,7 @@ TORRENT_TEST(init_dht_empty_bootstrap)
 {
 	settings_pack p = settings();
 	p.set_bool(settings_pack::enable_dht, true);
-	p.set_int(settings_pack::alert_mask, alert::all_categories);
+	p.set_int(settings_pack::alert_mask, alert_category::all);
 	// empty value
 	p.set_str(settings_pack::dht_bootstrap_nodes, "");
 
@@ -504,7 +504,7 @@ TORRENT_TEST(dht_upload_rate_overflow_pack)
 	// make sure this doesn't cause an overflow
 	p.set_int(settings_pack::dht_upload_rate_limit, std::numeric_limits<int>::max());
 	p.set_int(settings_pack::alert_mask, alert_category_t(std::uint32_t(p.get_int(settings_pack::alert_mask)))
-		| alert::dht_log_notification);
+		| alert_category::dht_log);
 	p.set_bool(settings_pack::enable_dht, true);
 	lt::session s(p);
 
@@ -520,7 +520,7 @@ TORRENT_TEST(dht_upload_rate_overflow)
 	settings_pack p = settings();
 	p.set_bool(settings_pack::enable_dht, true);
 	p.set_int(settings_pack::alert_mask, alert_category_t(std::uint32_t(p.get_int(settings_pack::alert_mask)))
-		| alert::dht_log_notification);
+		| alert_category::dht_log);
 	lt::session s(p);
 
 	// make sure this doesn't cause an overflow
@@ -577,7 +577,7 @@ TORRENT_TEST(reopen_network_sockets)
 	};
 
 	settings_pack p = settings();
-	p.set_int(settings_pack::alert_mask, alert::all_categories);
+	p.set_int(settings_pack::alert_mask, alert_category::all);
 	p.set_str(settings_pack::listen_interfaces, "127.0.0.1:6881l");
 
 	p.set_bool(settings_pack::enable_upnp, true);
diff --git a/test/test_torrent.cpp b/test/test_torrent.cpp
index a1e866840..d76172dbe 100644
--- a/test/test_torrent.cpp
+++ b/test/test_torrent.cpp
@@ -78,7 +78,7 @@ bool prioritize_files(torrent_handle const& h, aux::vector<download_priority_t,
 void test_running_torrent(std::shared_ptr<torrent_info> info, std::int64_t file_size)
 {
 	settings_pack pack = settings();
-	pack.set_int(settings_pack::alert_mask, alert::piece_progress_notification | alert::storage_notification);
+	pack.set_int(settings_pack::alert_mask, alert_category::piece_progress | alert_category::storage);
 	pack.set_str(settings_pack::listen_interfaces, "0.0.0.0:48130");
 	pack.set_int(settings_pack::max_retry_port_bind, 10);
 	lt::session ses(pack);
@@ -231,7 +231,7 @@ TORRENT_TEST(total_wanted)
 	auto info = std::make_shared<torrent_info>(tmp, from_span);
 
 	settings_pack pack = settings();
-	pack.set_int(settings_pack::alert_mask, alert::storage_notification);
+	pack.set_int(settings_pack::alert_mask, alert_category::storage);
 	pack.set_str(settings_pack::listen_interfaces, "0.0.0.0:48130");
 	pack.set_int(settings_pack::max_retry_port_bind, 10);
 	lt::session ses(pack);
@@ -761,7 +761,7 @@ TORRENT_TEST(symlinks_restore)
 	p.flags &= ~lt::torrent_flags::paused;
 	p.save_path = work_dir;
 	settings_pack pack = settings();
-	pack.set_int(libtorrent::settings_pack::alert_mask, libtorrent::alert::status_notification | libtorrent::alert::error_notification);
+	pack.set_int(libtorrent::settings_pack::alert_mask, libtorrent::alert_category::status | libtorrent::alert_category::error);
 	lt::session ses(std::move(pack));
 	ses.add_torrent(p);