diff --git a/src/brchess.c-move-to-temp-migration-bitboard__brchess.c b/src/brchess.c-move-to-temp-migration-bitboard__brchess.c
new file mode 100644
index 0000000..2661fdf
--- /dev/null
+++ b/src/brchess.c-move-to-temp-migration-bitboard__brchess.c
@@ -0,0 +1,522 @@
+/* brchess.c - main loop.
+ *
+ * Copyright (C) 2021-2023 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+
+#include <err.h>
+#include <stdlib.h>
+#include <string.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+
+#include <br.h>
+#include <list.h>
+#include <debug.h>
+
+#include "brchess.h"
+#include "chessdefs.h"
+#include "board.h"
+#include "piece.h"
+#include "move.h"
+#include "fen.h"
+#include "eval.h"
+#include "eval-simple.h"
+#include "search.h"
+
+struct command {
+    char *name;                                   /* User printable name */
+    int (*func)(pos_t *, char *);                 /* function doing the job */
+    char *doc;                                    /* function doc */
+};
+
+/* readline example inspired by :
+ * - https://thoughtbot.com/blog/tab-completion-in-gnu-readline
+ * - http://web.mit.edu/gnu/doc/html/rlman_2.html
+ */
+char **commands_completion(const char *, int, int);
+char *commands_generator(const char *, int);
+char *escape(const char *);
+int quote_detector(char *, int);
+int execute_line (pos_t *, char *line);
+struct command *find_command (char *);
+char *stripwhite (char *string);
+
+/* The names of functions that actually do the manipulation. */
+int do_help(pos_t *, char*);
+int do_fen(pos_t *, char*);
+int do_init(pos_t *, char*);
+int do_pos(pos_t *, char*);
+int do_genmoves(pos_t *, char*);
+int do_prmoves(pos_t *, char*);
+//int do_prmovepos(pos_t *pos, char *arg);
+int do_prpieces(pos_t *pos, char *arg);
+int do_memstats(pos_t *, char*);
+int do_eval(pos_t *, char*);
+int do_simple_eval(pos_t *, char*);
+int do_move(pos_t *, char*);
+int do_quit(pos_t *, char*);
+int do_debug(pos_t *, char*);
+int do_depth(pos_t *, char*);
+int do_search(pos_t *, char*);
+int do_pvs(pos_t *, char*);
+
+struct command commands[] = {
+    { "help", do_help, "Display this text" },
+    { "?", do_help, "Synonym for 'help'" },
+    { "fen", do_fen, "Set position to FEN" },
+    { "init", do_init, "Set position to normal start position" },
+    { "pos", do_pos, "Print current position" },
+    { "quit", do_quit, "Quit" },
+    { "genmove", do_genmoves, "Generate move list for " },
+    { "prmoves", do_prmoves, "Print position move list" },
+//    { "prmovepos", do_prmovepos, "Print Nth move resulting position" },
+    { "prpieces", do_prpieces, "Print Pieces (from pieces lists)" },
+    { "memstats", do_memstats, "Generate next move list" },
+    { "eval", do_eval, "Eval current position" },
+    { "simple-eval", do_simple_eval, "Simple eval current position" },
+    { "do_move", do_move, "execute nth move on current position" },
+    { "debug", do_debug, "Set log level to LEVEL" },
+    { "depth", do_depth, "Set search depth to N" },
+    { "search", do_search, "Search best move (negamax)" },
+    { "pvs", do_pvs, "Search best move (Principal Variation Search)" },
+    { NULL, (int(*)()) NULL, NULL }
+};
+
+static int done=0;
+static int depth=1;
+
+int brchess(pos_t *pos)
+{
+    char *buffer, *s;
+
+    rl_attempted_completion_function = commands_completion;
+    rl_completer_quote_characters = "'\"";
+    rl_completer_word_break_characters = " ";
+    rl_char_is_quoted_p = &quote_detector;
+
+    while (!done) {
+        buffer = readline("chess> ");
+        if (!buffer)
+            break;
+        /* Remove leading and trailing whitespace from the line.
+         * Then, if there is anything left, add it to the history list
+         * and execute it.
+         */
+        s = stripwhite(buffer);
+
+        if (*s) {
+            add_history(s);
+            execute_line(pos, s);
+        }
+        free(buffer);
+    }
+
+    return 0;
+}
+
+//char **commands_completion(const char *text, int start, int end)
+char **commands_completion(const char *text, __unused int start, __unused int end)
+{
+    rl_attempted_completion_over = 1;
+    return rl_completion_matches(text, commands_generator);
+}
+
+char *commands_generator(const char *text, int state)
+{
+    static int list_index, len;
+    char *name;
+
+    if (!state) {
+        list_index = 0;
+        len = strlen(text);
+    }
+
+    while ((name = commands[list_index++].name)) {
+        if (rl_completion_quote_character) {
+            name = strdup(name);
+        } else {
+            name = escape(name);
+        }
+
+        if (strncmp(name, text, len) == 0) {
+            return name;
+        } else {
+            free(name);
+        }
+    }
+
+    return NULL;
+}
+
+char *escape(const char *original)
+{
+    size_t original_len;
+    size_t i, j;
+    char *escaped, *resized_escaped;
+
+    original_len = strlen(original);
+
+    if (original_len > SIZE_MAX / 2) {
+        errx(1, "string too long to escape");
+    }
+
+    if ((escaped = malloc(2 * original_len + 1)) == NULL) {
+        err(1, NULL);
+    }
+
+    for (i = 0, j = 0; i < original_len; ++i, ++j) {
+        if (original[i] == ' ') {
+            escaped[j++] = '\\';
+        }
+        escaped[j] = original[i];
+    }
+    escaped[j] = '\0';
+
+    if ((resized_escaped = realloc(escaped, j)) == NULL) {
+        free(escaped);
+        resized_escaped = NULL;
+        err(1, NULL);
+    }
+
+    return resized_escaped;
+}
+
+int quote_detector(char *line, int index)
+{
+    return index > 0
+            && line[index - 1] == '\\'
+            &&!quote_detector(line, index - 1);
+}
+
+/* Execute a command line. */
+int execute_line(pos_t *pos, char *line)
+{
+    register int i;
+    struct command *command;
+    char *word;
+
+    /* Isolate the command word. */
+    i = 0;
+    while (line[i] && whitespace(line[i]))
+        i++;
+    word = line + i;
+
+    while (line[i] && !whitespace(line[i]))
+        i++;
+
+    if (line[i])
+        line[i++] = '\0';
+
+    command = find_command(word);
+
+    if (!command) {
+        fprintf(stderr, "%s: Unknown command.\n", word);
+        return -1;
+    }
+
+    /* Get argument to command, if any. */
+    while (whitespace(line[i]))
+        i++;
+
+    word = line + i;
+
+    /* return command number */
+    return (*command->func)(pos, word);
+}
+
+/* Look up NAME as the name of a command, and return a pointer to that
+   command.  Return a NULL pointer if NAME isn't a command name. */
+struct command *find_command(char *name)
+{
+    register int i;
+
+    for (i = 0; commands[i].name; i++)
+        if (strcmp(name, commands[i].name) == 0)
+            return &commands[i];
+
+    return (struct command *)NULL;
+}
+
+/* Strip whitespace from the start and end of STRING.  Return a pointer
+   into STRING. */
+char *stripwhite(char *string)
+{
+    register char *s, *t;
+
+    for (s = string; whitespace(*s); s++)
+        ;
+
+    if (*s == 0)
+        return s;
+
+    t = s + strlen(s) - 1;
+    while (t > s && whitespace(*t))
+        t--;
+    *++t = '\0';
+
+    return s;
+}
+
+int do_eval(__unused pos_t *pos, __unused char *arg)
+{
+    eval_t material[2], control[2], mobility[2];
+    for (int color = WHITE; color <= BLACK; ++color) {
+        material[color] = eval_material(pos, color);
+        control[color] = eval_square_control(pos, color);
+        mobility[color] = eval_mobility(pos, color);
+        printf("%s: material=%d mobility=%d controlled=%d\n",
+               color? "Black": "White", material[color],
+               mobility[color], control[color]);
+    }
+    eval_t res = eval(pos);
+    printf("eval = %d centipawns\n", res);
+    return 1;
+}
+
+int do_simple_eval(__unused pos_t *pos, __unused char *arg)
+{
+    eval_t eval = eval_simple(pos);
+    printf("eval = %d centipawns\n", eval);
+    return 1;
+}
+
+int do_fen(pos_t *pos, char *arg)
+{
+    fen2pos(pos, arg);
+    return 1;
+}
+
+int do_init(pos_t *pos, __unused char *arg)
+{
+    pos_startpos(pos);
+    return 1;
+}
+
+int do_pos(pos_t *pos, __unused char *arg)
+{
+    pos_print(pos);
+    return 1;
+}
+
+int do_genmoves(pos_t *pos, __unused char *arg)
+{
+    moves_gen_all(pos);
+    return 1;
+}
+
+int do_prmoves(pos_t *pos, __unused char *arg)
+{
+    uint debug_level = debug_level_get();
+    debug_level_set(1);
+    moves_print(pos, M_PR_SEPARATE | M_PR_NUM | M_PR_LONG);
+    debug_level_set(debug_level);
+    return 1;
+}
+
+/*
+ * int do_prmovepos(pos_t *pos, char *arg)
+ * {
+ *     struct list_head *p_cur, *tmp;
+ *     int movenum = atoi(arg), cur = 0;             /\* starts with 0 *\/
+ *     move_t *move;
+ *
+ *     log_f(1, "%s\n", arg);
+ *     list_for_each_safe(p_cur, tmp, &pos->moves[pos->turn]) {
+ *         move = list_entry(p_cur, move_t, list);
+ *         if (cur++ == movenum) {
+ *             pos_print(move->newpos);
+ *             break;
+ *         }
+ *     }
+ *
+ *     return 1;
+ * }
+ */
+
+int do_prpieces(pos_t *pos, __unused char *arg)
+{
+    log_f(1, "%s\n", arg);
+    pos_pieces_print(pos);
+    return 1;
+}
+
+int do_memstats(__unused pos_t *pos,__unused char *arg)
+{
+    moves_pool_stats();
+    piece_pool_stats();
+    pos_pool_stats();
+    return 1;
+}
+
+int do_move(__unused pos_t *pos, __unused char *arg)
+{
+    int i = 1, nmove = atoi(arg);
+    move_t *move;
+    pos_t *newpos;
+
+    if (list_empty(&pos->moves[pos->turn])) {
+        log_f(1, "No moves list.\n");
+        return 0;
+    }
+    list_for_each_entry(move, &pos->moves[pos->turn], list) {
+        if (i == nmove)
+            goto doit;
+        i++;
+    }
+    log_f(1, "Invalid <%d> move, should be <1-%d>.\n", nmove, i);
+    return 0;
+doit:
+    newpos = move_do(pos, move);
+    pos_print(newpos);
+
+    return 1;
+}
+
+int do_quit(__unused pos_t *pos, __unused char *arg)
+{
+    return done = 1;
+}
+
+int do_debug(__unused pos_t *pos, __unused char *arg)
+{
+    debug_level_set(atoi(arg));
+    return 1;
+}
+
+/* Print out help for ARG, or for all of the commands if ARG is
+   not present. */
+int do_help(__unused pos_t *pos, __unused char *arg)
+{
+    int i;
+    int printed = 0;
+
+    for (i = 0; commands[i].name; i++) {
+        if (!*arg || (strcmp(arg, commands[i].name) == 0)) {
+            printf("%-11.11s%s.\n", commands[i].name, commands[i].doc);
+            printed++;
+        }
+    }
+
+    if (!printed) {
+        printf("No commands match `%s'.  Possibilties are:\n", arg);
+
+        for (i = 0; commands[i].name; i++) {
+            /* Print in six columns. */
+            if (printed == 6) {
+                printed = 0;
+                printf("\n");
+            }
+
+            printf("%s\t", commands[i].name);
+            printed++;
+        }
+
+        if (printed)
+            printf("\n");
+    }
+    return 0;
+}
+
+int do_depth(__unused pos_t *pos, char *arg)
+{
+    depth = atoi(arg);
+    printf("depth = %d\n", depth);
+    return 1;
+
+}
+
+int do_search(pos_t *pos, __unused char *arg)
+{
+    int debug_level = debug_level_get();
+    float timer1, timer2, nodes_sec;
+
+    timer1 = debug_timer_elapsed();
+    negamax(pos, depth, pos->turn == WHITE ? 1 : -1);
+    timer2 = debug_timer_elapsed();
+    nodes_sec = (float) pos->node_count / ((float) (timer2 - timer1) / (float)NANOSEC);
+    log(1, "best=");
+    debug_level_set(1);
+    move_print(0, pos->bestmove, 0);
+    debug_level_set(debug_level);
+    log(1, " negamax=%d\n", pos->bestmove->negamax);
+    printf("Depth:%d Nodes:%luK time:%.02fs (%.0f kn/s)\n", depth,
+           pos->node_count / 1000, (timer2 - timer1)/NANOSEC, nodes_sec/1000);
+    return 1;
+}
+
+int do_pvs(pos_t *pos, __unused char *arg)
+{
+    int debug_level = debug_level_get();
+    float timer1, timer2, nodes_sec;
+    eval_t _pvs;
+
+    timer1 = debug_timer_elapsed();
+    moves_gen_eval_sort(pos);
+    _pvs = pvs(pos, depth, EVAL_MIN, EVAL_MAX, pos->turn == WHITE ? 1 : -1);
+    timer2 = debug_timer_elapsed();
+    nodes_sec = (float) pos->node_count / ((float) (timer2 - timer1) / (float)NANOSEC);
+    log(1, "best=");
+    if (pos->bestmove) {
+        debug_level_set(1);
+        move_print(0, pos->bestmove, 0);
+        debug_level_set(debug_level);
+        log(1, " pvs=%d stored=%d\n", _pvs, pos->bestmove->negamax);
+    } else {
+        log(1, "<no-best-move>");
+    }
+    printf("Depth:%d Nodes:%luK time:%.02fs (%.0f kn/s)\n", depth,
+           pos->node_count / 1000, (timer2 - timer1)/NANOSEC, nodes_sec/1000);
+    return 1;
+}
+
+/** main()
+ * options:
+ int brchess(pos_t *pos)
+ *
+ */
+static int usage(char *prg)
+{
+    fprintf(stderr, "Usage: %s [-ilw] [file...]\n", prg);
+    return 1;
+}
+
+#include <unistd.h>
+
+int main(int ac, char **av)
+{
+    pos_t *pos;
+    int opt;
+
+    piece_pool_init();
+    moves_pool_init();
+    pos_pool_init();
+    pos = pos_get();
+    debug_init(1, stderr, true);
+    eval_simple_init();
+
+    while ((opt = getopt(ac, av, "d:f:")) != -1) {
+        switch (opt) {
+            case 'd':
+                debug_level_set(atoi(optarg));
+                break;
+            case 'f':
+                fen2pos(pos, optarg);
+                break;
+            default:
+                return usage(*av);
+        }
+    }
+    if (optind < ac)
+        return usage(*av);
+
+    return brchess(pos);
+}