diff --git a/CHANGELOG.md b/CHANGELOG.md
index de9c7fe..5bfab60 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Negative numbers!
 - Version command via `:version` in REPL or `--version`, `-v` in command line.
 - Introduced start synchronization with builtins: `peers` and `start`
+- Connection with MIDI ports via parameters dropped in favour of function using context system: `port`
+- Listing ports via REPL command: `:ports` instead of commandline parameter
 
 ### Removed
 
diff --git a/musique/interpreter/builtin_functions.cc b/musique/interpreter/builtin_functions.cc
index aacc498..e692d64 100644
--- a/musique/interpreter/builtin_functions.cc
+++ b/musique/interpreter/builtin_functions.cc
@@ -322,13 +322,13 @@ Forward_Implementation(builtin_down, range<Range_Direction::Down>)
 static auto builtin_program_change(Interpreter &i, std::vector<Value> args) -> Result<Value> {
 	if (auto a = match<Number>(args)) {
 		auto [program] = *a;
-		i.midi_connection->send_program_change(0, program.as_int());
+		i.current_context->port->send_program_change(0, program.as_int());
 		return Value{};
 	}
 
 	if (auto a = match<Number, Number>(args)) {
 		auto [chan, program] = *a;
-		i.midi_connection->send_program_change(chan.as_int(), program.as_int());
+		i.current_context->port->send_program_change(chan.as_int(), program.as_int());
 		return Value{};
 	}
 
@@ -430,7 +430,7 @@ static Result<Value> builtin_par(Interpreter &interpreter, std::vector<Value> ar
 
 	for (auto const& note : chord->notes) {
 		if (note.base) {
-			interpreter.midi_connection->send_note_on(0, *note.into_midi_note(), 127);
+			interpreter.current_context->port->send_note_on(0, *note.into_midi_note(), 127);
 		}
 	}
 
@@ -438,7 +438,7 @@ static Result<Value> builtin_par(Interpreter &interpreter, std::vector<Value> ar
 
 	for (auto const& note : chord->notes) {
 		if (note.base) {
-			interpreter.midi_connection->send_note_off(0, *note.into_midi_note(), 127);
+			interpreter.current_context->port->send_note_off(0, *note.into_midi_note(), 127);
 		}
 	}
 	return result;
@@ -552,8 +552,8 @@ static Result<Value> builtin_sim(Interpreter &interpreter, std::vector<Value> ar
 			start_time = dur;
 		}
 		switch (instruction.action) {
-		break; case Instruction::On:  interpreter.midi_connection->send_note_on(0, instruction.note, 127);
-		break; case Instruction::Off: interpreter.midi_connection->send_note_off(0, instruction.note, 127);
+		break; case Instruction::On:  interpreter.current_context->port->send_note_on(0, instruction.note, 127);
+		break; case Instruction::Off: interpreter.current_context->port->send_note_off(0, instruction.note, 127);
 		}
 	}
 
@@ -1377,7 +1377,7 @@ static Result<Value> builtin_note_on(Interpreter &interpreter, std::vector<Value
 {
 	if (auto a = match<Number, Number, Number>(args)) {
 		auto [chan, note, vel] = *a;
-		interpreter.midi_connection->send_note_on(chan.as_int(), note.as_int(), vel.as_int());
+		interpreter.current_context->port->send_note_on(chan.as_int(), note.as_int(), vel.as_int());
 		return Value {};
 	}
 
@@ -1385,7 +1385,7 @@ static Result<Value> builtin_note_on(Interpreter &interpreter, std::vector<Value
 		auto [chan, chord, vel] = *a;
 		for (auto note : chord.notes) {
 			note = interpreter.current_context->fill(note);
-			interpreter.midi_connection->send_note_on(chan.as_int(), *note.into_midi_note(), vel.as_int());
+			interpreter.current_context->port->send_note_on(chan.as_int(), *note.into_midi_note(), vel.as_int());
 		}
 		return Value{};
 	}
@@ -1414,7 +1414,7 @@ static Result<Value> builtin_note_off(Interpreter &interpreter, std::vector<Valu
 {
 	if (auto a = match<Number, Number>(args)) {
 		auto [chan, note] = *a;
-		interpreter.midi_connection->send_note_off(chan.as_int(), note.as_int(), 127);
+		interpreter.current_context->port->send_note_off(chan.as_int(), note.as_int(), 127);
 		return Value {};
 	}
 
@@ -1423,7 +1423,7 @@ static Result<Value> builtin_note_off(Interpreter &interpreter, std::vector<Valu
 
 		for (auto note : chord.notes) {
 			note = interpreter.current_context->fill(note);
-			interpreter.midi_connection->send_note_off(chan.as_int(), *note.into_midi_note(), 127);
+			interpreter.current_context->port->send_note_off(chan.as_int(), *note.into_midi_note(), 127);
 		}
 		return Value{};
 	}
@@ -1601,6 +1601,39 @@ static Result<Value> builtin_peers(Interpreter &interpreter, std::vector<Value>)
 	return Number(interpreter.starter.peers());
 }
 
+static Result<Value> builtin_port(Interpreter &interpreter, std::vector<Value> args)
+{
+	if (args.empty()) {
+		for (auto const& [key, port] : Context::established_connections) {
+			if (port == interpreter.current_context->port) {
+				return std::visit(Overloaded {
+					[](midi::connections::Virtual_Port) { return Value(Symbol("virtual")); },
+					[](midi::connections::Established_Port port) { return Value(Number(port)); },
+				}, key);
+			}
+		}
+		unreachable();
+	}
+
+	if (auto a = match<Number>(args)) {
+		auto [port_number] = *a;
+		Try(interpreter.current_context->connect(port_number.floor().as_int()));
+		return {};
+	}
+
+	if (auto a = match<Symbol>(args)) {
+		auto [port_type] = *a;
+		if (port_type == "virtual") {
+			Try(interpreter.current_context->connect(std::nullopt));
+			return {};
+		}
+
+		unimplemented();
+	}
+
+	unimplemented();
+}
+
 void Interpreter::register_builtin_functions()
 {
 	auto &global = *Env::global;
@@ -1635,6 +1668,7 @@ void Interpreter::register_builtin_functions()
 	global.force_define("pgmchange",      builtin_program_change);
 	global.force_define("pick",           builtin_pick);
 	global.force_define("play",           builtin_play);
+	global.force_define("port",           builtin_port);
 	global.force_define("program_change", builtin_program_change);
 	global.force_define("range",          builtin_range);
 	global.force_define("reverse",        builtin_reverse);
diff --git a/musique/interpreter/context.cc b/musique/interpreter/context.cc
index 281860f..c2cc51f 100644
--- a/musique/interpreter/context.cc
+++ b/musique/interpreter/context.cc
@@ -12,3 +12,49 @@ std::chrono::duration<float> Context::length_to_duration(std::optional<Number> l
 	auto const len = length ? *length : this->length;
 	return std::chrono::duration<float>(float(len.num * (60.f / (float(bpm) / 4))) / len.den);
 }
+
+template<>
+struct std::hash<midi::connections::Key>
+{
+	std::size_t operator()(midi::connections::Key const& value) const
+	{
+		using namespace midi::connections;
+		return hash_combine(value.index(), std::visit(Overloaded {
+			[](Virtual_Port) { return 0u; },
+			[](Established_Port port) { return port; },
+		}, value));
+	}
+};
+
+std::unordered_map<midi::connections::Key, std::shared_ptr<midi::Connection>> Context::established_connections;
+
+/// Establish connection to given port
+std::optional<Error> Context::connect(std::optional<Port_Number> port_number)
+{
+	// FIXME This function doesn't support creating virtual ports when established ports are available
+	using namespace midi::connections;
+	auto const key = port_number ? Key(*port_number) : Key(Virtual_Port{});
+
+	if (auto it = established_connections.find(key); it != established_connections.end()) {
+		port = it->second;
+		return std::nullopt;
+	}
+
+	if (port_number) {
+		auto connection = std::make_shared<midi::Rt_Midi>();
+		connection->connect_output(*port_number);
+		established_connections[*port_number] = connection;
+		port = connection;
+		return std::nullopt;
+	}
+
+	auto connection = std::make_shared<midi::Rt_Midi>();
+	if (connection->connect_or_create_output()) {
+		established_connections[0u] = connection;
+	} else {
+		established_connections[Virtual_Port{}] = connection;
+	}
+	port = connection;
+	return std::nullopt;
+}
+
diff --git a/musique/interpreter/context.hh b/musique/interpreter/context.hh
index c85c0e2..5ab8412 100644
--- a/musique/interpreter/context.hh
+++ b/musique/interpreter/context.hh
@@ -1,11 +1,25 @@
 #ifndef MUSIQUE_CONTEXT_HH
 #define MUSIQUE_CONTEXT_HH
 
-#include <musique/common.hh>
-#include <musique/value/note.hh>
-#include <musique/value/number.hh>
 #include <chrono>
 #include <memory>
+#include <musique/common.hh>
+#include <musique/errors.hh>
+#include <musique/midi/midi.hh>
+#include <musique/value/note.hh>
+#include <musique/value/number.hh>
+
+namespace midi::connections
+{
+	using Established_Port = unsigned int;
+
+	struct Virtual_Port
+	{
+		bool operator==(Virtual_Port const&) const = default;
+	};
+
+	using Key = std::variant<Established_Port, Virtual_Port>;
+}
 
 /// Context holds default values for music related actions
 struct Context
@@ -19,6 +33,19 @@ struct Context
 	/// Default BPM
 	unsigned bpm = 120;
 
+	/// Port that is currently used
+	std::shared_ptr<midi::Connection> port;
+
+	using Port_Number = unsigned int;
+
+	/// Connections that have been established so far
+	static std::unordered_map<midi::connections::Key, std::shared_ptr<midi::Connection>> established_connections;
+
+	/// Establish connection to given port
+	///
+	/// If port number wasn't provided connect to first existing one or create one
+	std::optional<Error> connect(std::optional<Port_Number>);
+
 	/// Fills empty places in Note like octave and length with default values from context
 	Note fill(Note) const;
 
diff --git a/musique/interpreter/interpreter.cc b/musique/interpreter/interpreter.cc
index 10ac1e8..796bef8 100644
--- a/musique/interpreter/interpreter.cc
+++ b/musique/interpreter/interpreter.cc
@@ -7,7 +7,6 @@
 #include <random>
 #include <thread>
 
-midi::Connection *Interpreter::midi_connection = nullptr;
 std::unordered_map<std::string, Intrinsic> Interpreter::operators {};
 
 /// Registers constants like `fn = full note = 1/1`
@@ -265,7 +264,7 @@ std::optional<Error> Interpreter::play(Chord chord)
 	// Turn all notes on
 	for (auto const& note : chord.notes) {
 		if (note.base) {
-			midi_connection->send_note_on(0, *note.into_midi_note(), 127);
+			current_context->port->send_note_on(0, *note.into_midi_note(), 127);
 		}
 	}
 
@@ -276,16 +275,16 @@ std::optional<Error> Interpreter::play(Chord chord)
 			std::this_thread::sleep_for(ctx.length_to_duration(*note.length));
 		}
 		if (note.base) {
-			midi_connection->send_note_off(0, *note.into_midi_note(), 127);
+			current_context->port->send_note_off(0, *note.into_midi_note(), 127);
 		}
 	}
 
 	return {};
 }
 
-std::optional<Error> ensure_midi_connection_available(Interpreter &i, std::string_view operation_name)
+std::optional<Error> ensure_midi_connection_available(Interpreter &interpreter, std::string_view operation_name)
 {
-	if (i.midi_connection == nullptr || !i.midi_connection->supports_output()) {
+	if (interpreter.current_context->port == nullptr || !interpreter.current_context->port->supports_output()) {
 		return Error {
 			.details = errors::Operation_Requires_Midi_Connection {
 				.is_input = false,
diff --git a/musique/interpreter/interpreter.hh b/musique/interpreter/interpreter.hh
index d7ac8cf..325006c 100644
--- a/musique/interpreter/interpreter.hh
+++ b/musique/interpreter/interpreter.hh
@@ -10,10 +10,6 @@
 /// Given program tree evaluates it into Value
 struct Interpreter
 {
-	/// MIDI connection that is used to play music.
-	/// It's optional for simple interpreter testing.
-	static midi::Connection *midi_connection;
-
 	/// Operators defined for language
 	static std::unordered_map<std::string, Intrinsic> operators;
 
diff --git a/musique/main.cc b/musique/main.cc
index 15c4fc9..a62a4d6 100644
--- a/musique/main.cc
+++ b/musique/main.cc
@@ -68,11 +68,6 @@ static T pop(std::span<char const*> &span)
 		"usage: musique <options> [filename]\n"
 		"  where filename is path to file with Musique code that will be executed\n"
 		"  where options are:\n"
-		"    -o,--output PORT\n"
-		"      provides output port, a place where Musique produces MIDI messages\n"
-		"    -l,--list\n"
-		"      lists all available MIDI ports and quit\n"
-		"\n"
 		"    -c,--run CODE\n"
 		"      executes given code\n"
 		"    -I,--interactive,--repl\n"
@@ -105,6 +100,7 @@ void print_repl_help()
 		":!<command> - allows for execution of any shell command\n"
 		":clear - clears screen\n"
 		":load <file> - loads file into Musique session\n"
+		":ports - print list available ports"
 		;
 }
 
@@ -164,33 +160,16 @@ struct Runner
 {
 	static inline Runner *the;
 
-	midi::Rt_Midi midi;
 	Interpreter interpreter;
 
 	/// Setup interpreter and midi connection with given port
-	explicit Runner(std::optional<unsigned> output_port)
-		: midi()
-		, interpreter{}
+	explicit Runner()
+		: interpreter{}
 	{
 		ensure(the == nullptr, "Only one instance of runner is supported");
 		the = this;
 
-		interpreter.midi_connection = &midi;
-		if (output_port) {
-			midi.connect_output(*output_port);
-			if (!quiet_mode) {
-				std::cout << "Connected MIDI output to port " << *output_port << ". Ready to play!" << std::endl;
-			}
-		} else {
-			bool connected_to_existing_port = midi.connect_or_create_output();
-			if (!quiet_mode) {
-				if (connected_to_existing_port) {
-					std::cout << "Connected MIDI output to port " << midi.output->getPortName(0) << std::endl;
-				} else {
-					std::cout << "Created new MIDI output port 'Musique'. Ready to play!" << std::endl;
-				}
-			}
-		}
+		interpreter.current_context->connect(std::nullopt);
 
 		Env::global->force_define("say", +[](Interpreter &interpreter, std::vector<Value> args) -> Result<Value> {
 			for (auto it = args.begin(); it != args.end(); ++it) {
@@ -340,6 +319,14 @@ static Result<bool> handle_repl_session_commands(std::string_view input, Runner
 				return std::nullopt;
 			}
 		},
+
+		Command {
+			"ports",
+			+[](Runner&, std::optional<std::string_view>) -> std::optional<Error> {
+				midi::Rt_Midi{}.list_ports(std::cout);
+				return {};
+			},
+		},
 	};
 
 	if (input.starts_with('!')) {
@@ -384,9 +371,6 @@ static std::optional<Error> Main(std::span<char const*> args)
 		std::string_view argument;
 	};
 
-	// Arbitraly chosen for conviniance of the author
-	std::optional<unsigned> output_port{};
-
 	std::vector<Run> runnables;
 
 	while (not args.empty()) {
@@ -397,11 +381,6 @@ static std::optional<Error> Main(std::span<char const*> args)
 			continue;
 		}
 
-		if (arg == "-l" || arg == "--list") {
-			midi::Rt_Midi{}.list_ports(std::cout);
-			return {};
-		}
-
 		if (arg == "-c" || arg == "--run") {
 			if (args.empty()) {
 				std::cerr << "musique: error: option " << arg << " requires an argument" << std::endl;
@@ -439,15 +418,6 @@ static std::optional<Error> Main(std::span<char const*> args)
 			return {};
 		}
 
-		if (arg == "-o" || arg == "--output") {
-			if (args.empty()) {
-				std::cerr << "musique: error: option " << arg << " requires an argument" << std::endl;
-				std::exit(1);
-			}
-			output_port = pop<unsigned>(args);
-			continue;
-		}
-
 		if (arg == "-h" || arg == "--help") {
 			usage();
 		}
@@ -456,7 +426,7 @@ static std::optional<Error> Main(std::span<char const*> args)
 		std::exit(1);
 	}
 
-	Runner runner{output_port};
+	Runner runner;
 
 	for (auto const& [type, argument] : runnables) {
 		if (type == Run::Argument) {