diff --git a/TODO.md b/TODO.md
index 2432287..b50c863 100644
--- a/TODO.md
+++ b/TODO.md
@@ -5,8 +5,6 @@
 ## Current work
 
 * pass `indent` to `ColorizeFunc`.
-* `S-TAB` -> untabify
-* `TAB` and `S-TAB` with selected block -> indent, unindent block
 * `TAB` -> complete function name etc.
 * add parametric syntax definitions (nanorc files).
 * should implement a maximum macro length and abort macro learning mode if reached
@@ -128,7 +126,6 @@ both in `strtokey`
 * fix `eb_prev_char` to handle non self-synchronizing charsets
 * auto/mixed eol mode
 * `set-eol-type` should take a string: auto/binary/dos/unix/mac/0/1/2...
-* display `^L` as horizontal line and consider as linebreak character
 * handle zero width codepoints:
   cp="200B" na="ZERO WIDTH SPACE" alias="ZWSP"
   cp="200C" na="ZERO WIDTH NON-JOINER" alias="ZWNJ"
@@ -156,6 +153,7 @@ both in `strtokey`
 * fix current position when changing buffer attached to window
 * fix default wrap setting mess
 * display: add screen dump command and format
+* display `^L` as horizontal line and consider as linebreak character
 * colorize extra `^M` and `^Z` as preproc at end of line prior to calling the syntax highlighter (same as BOM)
 * colorizer bug on **/comp/projects/fractal/fractint/ORGFORM/NOEL-2.FRM** (triple `^M`)
 * display bug on **~/comp/projects/fractal/fractint/ORGFORM/BAILOUT.FRM** (double `^M`)
@@ -211,6 +209,9 @@ insert_window_left()  deletes some left-most windows
 * fix column computation based on display properties:
   (variable pitch, tabs, ^x and \uxxxx stuff -- emacs behaviour) ?
 
+* tag left-view with electric navigation
+* expand / collapse region
+
 ## X11 display / graphics
 
 * handle X11 window manager close window event and exit cleanly
@@ -278,7 +279,6 @@ insert_window_left()  deletes some left-most windows
   * `what-cursor-position` with universal prefix: show popup with long description
   * `compare-windows` should resync from the end of line.
   * `elastic-tabs`
-  * `indent-rigidly`
   * `show-matching-delimiters`
   * blink-and-insert on `) } ] >`
   * `set-gosmacs-bindings` -> `set_emulation("gosmacs")`
diff --git a/extras.c b/extras.c
index 1537a28..41441b6 100644
--- a/extras.c
+++ b/extras.c
@@ -724,12 +724,75 @@ static void do_indent_region(EditState *s, int start, int end)
             (s->mode->indent_func)(s, eb_goto_pos(s->b, line1, 0));
         } else {
             s->offset = eb_goto_pos(s->b, line1, 0);
-            do_tab(s, 1);
+            do_tabulate(s, 1);
         }
     }
     s->offset = eb_goto_eol(s->b, s->offset);
 }
 
+void do_indent_rigidly(EditState *s, int start, int end, int argval)
+{
+    int col_num, line1, line2;
+
+    if (argval == NO_ARG) {
+        // enter interactive mode
+        QEmacsState *qs = s->qe_state;
+        if (!qs->first_transient_key) {
+            s->region_style = QE_STYLE_REGION_HILITE;
+            put_status(s, "indent the region interactively with TAB, left, right, S-left, S-right");
+            qe_register_transient_binding(qs, "indent-rigidly-left", "left");
+            qe_register_transient_binding(qs, "indent-rigidly-right", "right");
+            qe_register_transient_binding(qs, "indent-rigidly-left-to-tab-stop", "S-left, S-TAB");
+            qe_register_transient_binding(qs, "indent-rigidly-right-to-tab-stop", "S-right, TAB");
+        }
+        return;
+    }
+
+    /* Swap point and mark so mark <= point */
+    if (end < start) {
+        int tmp = start;
+        end = start;
+        start = tmp;
+    }
+    /* We do it with lines to avoid offset variations during indenting */
+    eb_get_pos(s->b, &line1, &col_num, start);
+    eb_get_pos(s->b, &line2, &col_num, end);
+
+    if (col_num == 0)
+        line2--;
+
+    /* Iterate over all lines inside block */
+    //s->b->mark = eb_goto_bol(s->b, start);
+    for (; line1 <= line2; line1++) {
+        int offset = eb_goto_pos(s->b, line1, 0);
+        int off1, off2;
+        int indent = find_indent(s, offset, 0, &off1);
+        int new_indent = max_int(0, indent + argval);
+        if (eb_nextc(s->b, off1, &off2) == '\n')
+            new_indent = 0;
+        make_indent(s, offset, off1, 0, new_indent);
+    }
+    //s->offset = eb_goto_eol(s->b, s->offset);
+}
+
+static void do_indent_rigidly_to_tab_stop(EditState *s, int start, int end, int dir) {
+    int tw = s->b->tab_width > 0 ? s->b->tab_width : DEFAULT_TAB_WIDTH;
+    int indent = s->indent_size > 0 ? s->indent_size : tw;
+
+    do_indent_rigidly(s, start, end, indent * dir);
+}
+
+static void do_untabulate(EditState *s) {
+    if (s->region_style) {
+        do_indent_rigidly_to_tab_stop(s, s->b->mark, s->offset, -1);
+    } else {
+        // FIXME: should decrease indentation at s->offset
+        int start = eb_goto_bol(s->b, s->offset);
+        int end = eb_goto_eol(s->b, s->offset);
+        do_indent_rigidly_to_tab_stop(s, start, end, -1);
+    }
+}
+
 void do_show_date_and_time(EditState *s, int argval)
 {
     time_t t = argval;
@@ -2612,6 +2675,24 @@ static const CmdDef extra_commands[] = {
     CMD2( "indent-buffer", "",
           "Indent each nonblank line in the buffer",
           do_indent_region, ESii, "*" "ze")
+    CMD2( "indent-rigidly", "C-x TAB",
+          "Indent the region interactively",
+          do_indent_rigidly, ESiii, "*" "md" "P")
+    CMD3( "indent-rigidly-left", "",
+          "Decrease the region indentation",
+          do_indent_rigidly, ESiii, "*" "md" "v", -1)
+    CMD3( "indent-rigidly-right", "",
+          "Increase the region indentation",
+          do_indent_rigidly, ESiii, "*" "md" "v", +1)
+    CMD3( "indent-rigidly-left-to-tab-stop", "",
+          "Decrease the region indentation by one tab",
+          do_indent_rigidly_to_tab_stop, ESiii, "*" "md" "v", -1)
+    CMD3( "indent-rigidly-right-to-tab-stop", "",
+          "Increase the region indentation by one tab",
+          do_indent_rigidly_to_tab_stop, ESiii, "*" "md" "v", +1)
+    CMD2( "untabulate", "S-TAB",
+          "Decrease indentation",
+          do_untabulate, ES, "*")
 
     CMD2( "show-date-and-time", "C-x t",
           "Show current date and time",
diff --git a/lang/clang.c b/lang/clang.c
index 7fb8e00..19f55be 100644
--- a/lang/clang.c
+++ b/lang/clang.c
@@ -1121,11 +1121,12 @@ done:
 
 static void do_c_indent(EditState *s)
 {
-    if (eb_is_in_indentation(s->b, s->offset)
+    if (!s->region_style
+    &&  eb_is_in_indentation(s->b, s->offset)
     &&  s->qe_state->last_cmd_func != (CmdFunc)do_c_indent) {
         c_indent_line(s, s->offset);
     } else {
-        do_tab(s, 1);
+        do_tabulate(s, 1);
     }
 }
 
diff --git a/modes/shell.c b/modes/shell.c
index c4a24b8..f2e1e6e 100644
--- a/modes/shell.c
+++ b/modes/shell.c
@@ -3157,6 +3157,7 @@ static void do_shell_tabulate(EditState *e)
     if (e->interactive) {
         shell_write_char(e, 9);
     } else {
+        //do_tabulate(s, 1);
         text_write_char(e, 9);
     }
 }
diff --git a/qe.c b/qe.c
index cac6f76..d895c3f 100644
--- a/qe.c
+++ b/qe.c
@@ -1042,7 +1042,7 @@ void do_backspace(EditState *s, int argval)
     if (argval == NO_ARG) {
         // XXX: this does not work for c-mode
         // XXX: should implement backward-delete-char-untabify instead
-        if (s->qe_state->last_cmd_func == (CmdFunc)do_tab
+        if (s->qe_state->last_cmd_func == (CmdFunc)do_tabulate
         &&  !s->indent_tabs_mode && !s->multi_cursor_active) {
             /* Delete tab or indentation? */
             do_undo(s);
@@ -1926,17 +1926,86 @@ void do_overwrite_mode(EditState *s, int argval) {
     put_status(s, "Overwrite mode is %s", s->overwrite ? "on" : "off");
 }
 
-void do_tab(EditState *s, int argval)
+/* get the indentation width at a given offset */
+int find_indent(EditState *s, int offset, int pos, int *offsetp) {
+    int tw = s->b->tab_width > 0 ? s->b->tab_width : 8;
+    int offset1;
+    for (;; offset = offset1) {
+        char32_t c = eb_nextc(s->b, offset, &offset1);
+        if (c == '\t')
+            pos += tw - (pos % tw);
+        else if (c == ' ')
+            pos++;
+        else
+            break;
+    }
+    *offsetp = offset;
+    return pos;
+}
+
+static void get_indent_chars(EditState *s, int pos, int target,
+                             int *ptabs, int *pspaces)
 {
+    int tabs = 0, spaces = 0;
+    if (target > pos) {
+        if (s->indent_tabs_mode) {
+            int tw = s->b->tab_width > 0 ? s->b->tab_width : 8;
+            while (target >= pos + tw - pos % tw) {
+                tabs++;
+                pos += tw - pos % tw;
+            }
+        }
+        spaces = target - pos;
+    }
+    *ptabs = tabs;
+    *pspaces = spaces;
+}
+
+/* replace characters in region with specified TABs and spaces */
+static int replace_indent(EditState *s, int offset, int end, int tabs, int spaces) {
+    int offset1;
+    while (offset < end) {
+        char32_t c = eb_nextc(s->b, offset, &offset1);
+        if (tabs && c == '\t') {
+            tabs--;
+        } else
+        if (spaces && c == ' ') {
+            spaces--;
+        } else {
+            break;
+        }
+        offset = offset1;
+    }
+    eb_delete_range(s->b, offset, end);
+    offset += eb_insert_char32_n(s->b, offset, '\t', tabs);
+    offset += eb_insert_char32_n(s->b, offset, ' ', spaces);
+    return offset;
+}
+
+int make_indent(EditState *s, int offset, int end, int pos, int target) {
+    int tabs, spaces;
+    get_indent_chars(s, pos, target, &tabs, &spaces);
+    return replace_indent(s, offset, end, tabs, spaces);
+}
+
+void do_tabulate(EditState *s, int argval)
+{
+    int tw = s->b->tab_width > 0 ? s->b->tab_width : DEFAULT_TAB_WIDTH;
+    int indent = s->indent_size > 0 ? s->indent_size : tw;
+
     /* CG: should do smart complete, smart indent, insert tab */
+#ifndef CONFIG_TINY
+    if (s->region_style) {
+        do_indent_rigidly(s, s->b->mark, s->offset, indent);
+        return;
+    }
+#endif
     if (s->indent_tabs_mode) {
         do_char(s, '\t', argval);
     } else {
         int offset = s->offset;
         int offset0 = eb_goto_bol(s->b, offset);
         int col = 0;
-        int tw = s->b->tab_width > 0 ? s->b->tab_width : DEFAULT_TAB_WIDTH;
-        int indent = s->indent_size > 0 ? s->indent_size : tw;
 
         while (offset0 < offset) {
             char32_t c = eb_nextc(s->b, offset0, &offset0);
@@ -10330,10 +10399,10 @@ static const CmdDef basic_commands[] = {
           do_char, ESii, "*"
           "n{Insert char: }[charname]|charvalue|"
           "p")
-    /* do_tab will not change read only buffer */
+    /* do_tabulate will not change read only buffer */
     CMD2( "tabulate", "TAB",
           "Insert a TAB or spaces according to indent-tabs-mode",
-          do_tab, ESi, "p")
+          do_tabulate, ESi, "p")
     //CMD2( "space", "SPC", "Insert a space", do_space, ESi, "*" "P")
     CMD2( "quoted-insert", "C-q",
           "Read next input character and insert it",
diff --git a/qe.h b/qe.h
index cf074b0..cb454aa 100644
--- a/qe.h
+++ b/qe.h
@@ -1502,7 +1502,7 @@ void do_newline(EditState *s);
 void do_open_line(EditState *s);
 void do_backspace(EditState *s, int argval);
 void do_delete_char(EditState *s, int argval);
-void do_tab(EditState *s, int argval);
+void do_tabulate(EditState *s, int argval);
 EditBuffer *new_yank_buffer(QEmacsState *qs, EditBuffer *base);
 void do_append_next_kill(EditState *s);
 void do_kill(EditState *s, int p1, int p2, int dir, int keep);
@@ -1585,6 +1585,8 @@ void do_toggle_truncate_lines(EditState *s);
 void do_word_wrap(EditState *s);
 void do_count_lines(EditState *s);
 void do_what_cursor_position(EditState *s);
+int find_indent(EditState *s, int offset, int pos, int *offsetp);
+int make_indent(EditState *s, int offset, int end, int pos, int target);
 void do_set_tab_width(EditState *s, int tab_width);
 void do_set_indent_width(EditState *s, int indent_width);
 void do_set_indent_tabs_mode(EditState *s, int val);
@@ -1762,6 +1764,7 @@ void do_compare_windows(EditState *s, int argval);
 void do_compare_files(EditState *s, const char *filename, int bflags);
 void do_delete_horizontal_space(EditState *s);
 void do_show_date_and_time(EditState *s, int argval);
+void do_indent_rigidly(EditState *s, int start, int end, int argval);
 
 enum {
     CMD_TRANSPOSE_CHARS = 1,