diff --git a/CMakeLists.txt b/CMakeLists.txt
index 50bc886..572de7c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.25)
 project(dynamic_program CXX)
 
 set(CMAKE_CXX_STANDARD 20)
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wpedantic -Werror")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wpedantic -Werror -lreadline")
 set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O3")
 
 find_package(cpr)
@@ -11,7 +11,7 @@ FIND_PACKAGE( Boost 1.81 COMPONENTS program_options REQUIRED )
 include_directories(.)
 INCLUDE_DIRECTORIES( ${Boost_INCLUDE_DIR} )
 
-add_executable(dynamic_program main.cpp game_state.h)
+add_executable(dynamic_program main.cpp game_state.h cli_interface.cpp)
 
 target_link_libraries(dynamic_program cpr)
 TARGET_LINK_LIBRARIES(dynamic_program Boost::program_options )
diff --git a/cli_interface.cpp b/cli_interface.cpp
new file mode 100644
index 0000000..0f4ec78
--- /dev/null
+++ b/cli_interface.cpp
@@ -0,0 +1,155 @@
+#include <cstdio>
+#include <readline/readline.h>
+#include <iostream>
+#include <memory>
+#include <cmath>
+#include "game_state.h"
+
+namespace Hanabi {
+
+    std::ostream& operator<<(std::ostream& os, const std::optional<probability_t>& prob) {
+        if (prob.has_value()) {
+            os << prob.value() << " ~ " << std::setprecision(5) << boost::rational_cast<double>(prob.value()) * 100 << "%";
+        } else {
+            os << "unknown";
+        }
+        return os;
+    }
+
+    std::string read_line_memory_safe(const char *prompt) {
+        char *line = readline(prompt);
+        std::string ret;
+        if (line == nullptr) {
+            ret = "";
+        } else {
+            ret = std::string(line);
+        }
+        free(line);
+        return ret;
+    }
+
+    Card parse_card(std::string card_str) {
+        if(card_str.size() != 2) {
+            return unknown_card;
+        }
+        constexpr std::array<char, 6> color_initials = {'r', 'y', 'g', 'b', 'p', 't'};
+        auto it = std::find(color_initials.begin(), color_initials.end(), card_str[0]);
+        if (it == color_initials.end()) {
+            return unknown_card;
+        }
+        const suit_t suit = std::distance(color_initials.begin(), it);
+        try {
+            const rank_t rank = 5 - std::stoi(card_str.substr(1, 1));
+            return Card {suit, rank};
+        } catch(std::invalid_argument&) {
+            return unknown_card;
+        }
+    }
+
+    bool ask_for_card_and_rotate_draw(const std::shared_ptr<HanabiStateIF>& game, hand_index_t index, bool play) {
+        const auto next_states = game->possible_next_states(index, play);
+        if (next_states.size() <= 1) {
+            return true;
+        }
+        std::cout << "Choose drawn card: " << std::endl;
+        for(const auto &[card_multiplicity, probability]: next_states) {
+            if (game->is_trash(card_multiplicity.card)) {
+                std::cout << "kt " << std::endl;
+            } else {
+                std::cout << card_multiplicity.card << " ";
+            }
+            std::cout << "(" << card_multiplicity.multiplicity << " copie(s) in draw) " << probability << std::endl;
+        }
+        const std::string card_str = read_line_memory_safe("draw? ");
+        const Card drawn_card = parse_card(card_str);
+        if (drawn_card == unknown_card) {
+            std::cout << "Could not parse card " << card_str << std::endl;
+            return false;
+        }
+
+        if (std::find_if(next_states.begin(), next_states.end(), [&drawn_card](const std::pair<CardMultiplicity, std::optional<probability_t>>& pair) {
+            return pair.first.card.suit == drawn_card.suit and pair.first.card.rank == drawn_card.rank;
+        }) == next_states.end()) {
+            std::cout << "That card is not in the draw pile" << std::endl;
+        };
+        game->rotate_next_draw(drawn_card);
+        return true;
+    }
+
+    [[noreturn]] void cli(const std::shared_ptr<HanabiStateIF>& game) {
+        while (true) {
+            const std::string prompt = read_line_memory_safe("> ");
+
+            if (prompt.starts_with("help")) {
+                std::cout << "state: print information on current game state" << std::endl;
+                std::cout << "clue: give a clue" << std::endl;
+                std::cout << "play <card>: play specified card" << std::endl;
+                std::cout << "discard <card>: discard specified card" << std::endl;
+                std::cout << "revert: revert last turn of game" << std::endl;
+                std::cout << "actions: display list of reasonable actions to take and their winning chances" << std::endl;
+                continue;
+            }
+
+            if (prompt.starts_with("state")) {
+                std::cout << *game << std::endl;
+                const std::optional<probability_t> prob = game->lookup();
+                std::cout << "Winning chance: " << prob << std::endl;
+                continue;
+            }
+
+            if (prompt.starts_with("revert")) {
+                std::cout << "Reverting one turn" << std::endl;
+                game->revert();
+                continue;
+            }
+
+            if (prompt.starts_with("play")) {
+                const Card card = parse_card(prompt.substr(5,2));
+                if (card == unknown_card) {
+                    std::cout << "Could not parse card " << prompt.substr(5,2) << std::endl;
+                    continue;
+                }
+                const hand_index_t index = game->find_card_in_hand(card);
+                if (index == hand_index_t(-1)) {
+                    std::cout << "This card is not in the current players hand, aborting." << std::endl;
+                }
+                if (!ask_for_card_and_rotate_draw(game, index, true)) {
+                    continue;
+                }
+                game->play(index);
+                continue;
+            }
+
+            if (prompt.starts_with("discard")) {
+                const Card card = parse_card(prompt.substr(8,2));
+                if (card == unknown_card) {
+                    std::cout << "Could not parse card " << prompt.substr(5,2) << std::endl;
+                    continue;
+                }
+                const hand_index_t index = game->find_card_in_hand(card);
+                if (index == hand_index_t(-1)) {
+                    std::cout << "This card is not in the current players hand, aborting." << std::endl;
+                }
+                if (!ask_for_card_and_rotate_draw(game, index, false)) {
+                    continue;
+                }
+                game->discard(index);
+                continue;
+            }
+
+            if (prompt.starts_with("clue")) {
+                game->clue();
+                continue;
+            }
+
+            if (prompt.starts_with("actions")) {
+                for (const auto &[action, probability] : game->get_reasonable_actions()) {
+                    std::cout << action << ": " << probability << std::endl;
+                }
+                continue;
+            }
+
+            std::cout << "Unrecognized command. Type 'help' for a list of available commands." << std::endl;
+        }
+    }
+}
\ No newline at end of file
diff --git a/cli_interface.h b/cli_interface.h
new file mode 100644
index 0000000..21e05d6
--- /dev/null
+++ b/cli_interface.h
@@ -0,0 +1,12 @@
+#ifndef DYNAMIC_PROGRAM_CLI_INTERFACE_H
+#define DYNAMIC_PROGRAM_CLI_INTERFACE_H
+
+#include <memory>
+#include "game_state.h"
+
+namespace Hanabi {
+    [[noreturn]] [[noreturn]] void cli(const std::shared_ptr<HanabiStateIF>& game);
+}
+
+
+#endif //DYNAMIC_PROGRAM_CLI_INTERFACE_H
diff --git a/game_state.h b/game_state.h
index c0cbe3c..438eb17 100644
--- a/game_state.h
+++ b/game_state.h
@@ -8,6 +8,7 @@
 #include <cstddef>
 #include <unordered_map>
 #include <bitset>
+#include <vector>
 #include <limits>
 #include <optional>
 #include <boost/container/static_vector.hpp>
@@ -48,9 +49,9 @@ namespace Hanabi {
         bool in_starting_hand;
         bool initial_trash;
 
-        Card &operator++();
+        inline Card &operator++();
 
-        const Card operator++(int);
+        inline const Card operator++(int);
 
         auto operator<=>(const Card &) const = default;
     };
@@ -67,7 +68,7 @@ namespace std {
 
 namespace Hanabi {
 
-std::ostream &operator<<(std::ostream &os, const Card &card);
+inline std::ostream &operator<<(std::ostream &os, const Card &card);
 
 constexpr Card r0 = {0, 5};
 constexpr Card r1 = {0, 4};
@@ -99,7 +100,7 @@ std::ostream& operator<<(std::ostream &os, const Stacks<num_suits> &stacks);
 
 struct CardMultiplicity {
   Card card;
-  std::uint8_t multiplicity;
+  unsigned multiplicity;
 
   auto operator<=>(const CardMultiplicity &) const = default;
 };
@@ -150,7 +151,7 @@ struct Action {
     Card card {};
 };
 
-std::ostream& operator<<(std::ostream& os, const Action& action);
+inline std::ostream& operator<<(std::ostream& os, const Action& action);
 
 /** Would like to have 2 versions:
  * All:
@@ -181,8 +182,10 @@ public:
     virtual void init_backtracking_information() = 0;
     virtual probability_t evaluate_state() = 0;
 
+    virtual std::optional<probability_t> lookup() const = 0;
+
     virtual std::vector<std::pair<Action, std::optional<probability_t>>> get_reasonable_actions() = 0;
-    virtual std::vector<std::pair<CardMultiplicity,probability_t>> possible_next_states(hand_index_t index, bool play) = 0;
+    virtual std::vector<std::pair<CardMultiplicity, std::optional<probability_t>>> possible_next_states(hand_index_t index, bool play) = 0;
 
     virtual ~HanabiStateIF() = default;
 
@@ -192,6 +195,8 @@ protected:
     friend std::ostream& operator<<(std::ostream&, HanabiStateIF const&);
 };
 
+inline std::ostream &operator<<(std::ostream &os, HanabiStateIF const &hanabi_state);
+
 template <suit_t num_suits, player_t num_players, hand_index_t hand_size>
 class HanabiState : public HanabiStateIF {
 public:
@@ -221,7 +226,7 @@ public:
     std::optional<probability_t> lookup() const;
 
     std::vector<std::pair<Action, std::optional<probability_t>>> get_reasonable_actions() final;
-    std::vector<std::pair<CardMultiplicity,probability_t>> possible_next_states(hand_index_t index, bool play) final;
+    std::vector<std::pair<CardMultiplicity, std::optional<probability_t>>> possible_next_states(hand_index_t index, bool play) final;
 
     auto operator<=>(const HanabiState &) const = default;
 
@@ -274,7 +279,7 @@ private:
     unsigned long discard_and_potentially_update(hand_index_t index);
     unsigned long play_and_potentially_update(hand_index_t index);
 
-    unsigned long draw(hand_index_t index);
+    unsigned draw(hand_index_t index);
 
     void revert_draw(hand_index_t index, Card discarded_card);
     void revert_clue();
diff --git a/game_state.hpp b/game_state.hpp
index 0cfa684..1815a09 100644
--- a/game_state.hpp
+++ b/game_state.hpp
@@ -244,7 +244,7 @@ namespace Hanabi {
     }
 
     template<suit_t num_suits, player_t num_players, hand_index_t hand_size>
-    unsigned long HanabiState<num_suits, num_players, hand_size>::draw(uint8_t index) {
+    unsigned HanabiState<num_suits, num_players, hand_size>::draw(uint8_t index) {
         ASSERT(index < _hands[_turn].size());
 
         // update card position of the card we are about to discard
@@ -470,18 +470,17 @@ namespace Hanabi {
     }
 
     template<suit_t num_suits, player_t num_players, hand_index_t hand_size>
-    std::vector<std::pair<CardMultiplicity, probability_t>> HanabiState<num_suits, num_players, hand_size>::possible_next_states(hand_index_t index, bool play) {
-        std::vector<std::pair<CardMultiplicity, probability_t>> next_states;
-        do_for_each_potential_draw(index, play, [this, &next_states](unsigned long multiplicity){
+    std::vector<std::pair<CardMultiplicity, std::optional<probability_t>>> HanabiState<num_suits, num_players, hand_size>::possible_next_states(hand_index_t index, bool play) {
+        std::vector<std::pair<CardMultiplicity, std::optional<probability_t>>> next_states;
+        do_for_each_potential_draw(index, play, [this, &next_states, &index](unsigned multiplicity){
             auto prob = lookup();
-            ASSERT(lookup().has_value());
 
             // bit hacky to get drawn card here
             decr_turn();
-            const CardMultiplicity drawn_card = {_hands[_turn], multiplicity};
+            const CardMultiplicity drawn_card = {_hands[_turn][index], multiplicity};
             incr_turn();
 
-            next_states.emplace_back(drawn_card, prob.value());
+            next_states.emplace_back(drawn_card, prob);
         });
         return next_states;
     }
diff --git a/main.cpp b/main.cpp
index 7c7d620..a93b399 100644
--- a/main.cpp
+++ b/main.cpp
@@ -11,6 +11,7 @@
 #include "game_state.h"
 #include "download.h"
 #include "myassert.h"
+#include "cli_interface.h"
 
 
 namespace Hanabi {
@@ -23,20 +24,6 @@ namespace Hanabi {
         std::cout << "Probability with optimal play: " << res << std::endl;
         std::cout << "Enumerated " << game->enumerated_states() << " states" << std::endl;
         std::cout << "Visited " << game->position_tablebase().size() << " unique game states. " << std::endl;
-
-        game->rotate_next_draw(r1);
-        game->discard(0);
-
-        game->rotate_next_draw(r1);
-        game->play(game->find_card_in_hand(y3));
-
-        game->clue();
-
-        game->rotate_next_draw(r1);
-        game->play(game->find_card_in_hand(y4));
-
-        std::cout << *game << std::endl;
-
         for (const auto &[action, probability] : game->get_reasonable_actions()) {
             std::cout << action;
             if(probability.has_value()) {
@@ -52,6 +39,10 @@ namespace Hanabi {
             biggest_key = std::max(biggest_key, key);
         }
         std::cout << "Biggest key generated is " << biggest_key << std::endl;
+
+        auto game_shared = std::shared_ptr<HanabiStateIF>(game.release());
+        auto states = game_shared->possible_next_states(0, false);
+        cli(game_shared);
     }
 
     void print_sizes() {