diff -uNr a/yrc/codemap.txt b/yrc/codemap.txt
--- a/yrc/codemap.txt e17fe3855e0266ce8a34fcd51a3c38da6ef09219e932222ee8e844a40ec1e218796f8be809eb442dc0cf0c9246ad389c6806d6ee424fdf8c77deb7d1627c530b
+++ b/yrc/codemap.txt f168745fe71becbdcc6ff376d2afb22492b11aa45d4c44d58203bcef49c57f8b1c634b8fa659a4a273ed64cc89066f0bdfce4a23a8d87e3ea0bf978900a7ae10
@@ -50,6 +50,10 @@
 - prompt
 - ping_draw
 
+ring
+- start: int
+- list: list
+
 Enumerations
 ============
 
@@ -95,6 +99,8 @@
 out_buf: bytearray
 kbd_accum: bytearray
 kbd_state: function
+history_pos: int | None
+history_stash: str | None
 
 Collections
 ===========
@@ -105,6 +111,7 @@
 open_conns: (fileno: int) => conn
 network_conns: (network: str) => conn : all enabled networks, whether TCP alive or not
 schedule: min-heap of (time: float) => thunk
+history_ring: ring of str
 
 Functions
 =========
@@ -172,6 +179,8 @@
 empty2
 lterr / TypeError
 format_log_msg(val: message except (m_chantopic | m_mode | m_client)) -> str
+ring_index(ring, int) -> int
+ring_get(ring of t, int) -> t | None
 
 Pure I/O:
 write_all(blocking fd, str|bytearray) / EnvironmentError
@@ -210,6 +219,9 @@
 close_buf(buf)
 prompt_insert(chr)
 prompt_submit
+prompt_end
+history_prev
+history_next
 prompt_backspace
 prompt_delete
 info(msg: str, buf=None) : buf_log_msg to buf or buffers[0]
@@ -242,6 +254,9 @@
 handle_resize
 mono_time -> float
 run_in(seconds, thunk)
+ring_set(ring of t, int, t)
+ring_rotate(ring, int)
+ring_append(ring of t, t)
 
 Slash commands:
 quit_cmd
diff -uNr a/yrc/manifest b/yrc/manifest
--- a/yrc/manifest 562aeaf072a99dfa4950c8215b3a74da57a2d743d4bcc1a25d51a8c85f4b22e1c3c1d705a5cead9b97e232dcb701251b05b18b27bd4e8667505ca3d63396e4ec
+++ b/yrc/manifest 2463d27af64f5b54459d437aa1b1f9e387e65a3d13e4fa4faed466f3f55462f6c54876d08efbbcbec53d5f918152e3bb6c7c05f9f7e2e2d1679864417d53f283
@@ -2,3 +2,4 @@
 633652 yrc_linear_scroll_etc jfw Version 96K with smooth/linear scrolling, Python 2.6 compat, yrc2local log formatter, bugfixes and more: see NEWS for details.
 768770 yrc_minor_refactors_reorders jfw Move prompt_clear to a higher layer by making it use the prompt_chars accessor: it now deletes entries from a fixed character list container rather than replacing the list as a whole. Expand prompt_backspace not to stack on top of prompt_delete, coming out only slightly longer. Tighten some prompt commands (such as backspace/delete) to skip unnecessary redraw. In codemap.txt, reclassify commands dict as a quasiconstant since it doesn't change after startup.
 768773 yrc_minor_command_reorder jfw Move prompt_backspace and prompt_delete implementations to match the more sensible order in keymap and manual.
+768773 yrc_input_history jfw Implement input history, by use of a new data structure for rings (cyclic lists).
diff -uNr a/yrc/yrc.py b/yrc/yrc.py
--- a/yrc/yrc.py 40e09cc21c0e83b9dd8610577fe63c82f5bca1b384e0a37dd791482081f4ecc30efcd2eb9a706e2bb954e0d99bc77e6d115b34696aa2506854b941c22066f052
+++ b/yrc/yrc.py 6d38419516970f97781c49217aabffa72ddb540773b30b479a0c25c7dc503083f95ac4c99d9cfef2762f2abd146ae677c1aaf1421b8e791c06c35d4e62ddb9ba
@@ -7,6 +7,8 @@
 __version__ = '96 Kelvin'
 
 # Knobs that one might conceivably want to tweak
+KILL_RING_SIZE = 8
+HISTORY_RING_SIZE = 1024
 DEFAULT_PORT = 6667
 RECONN_DELAY_MIN = 4 # seconds
 RECONN_DELAY_MAX = 256
@@ -88,6 +90,12 @@
 	END: 'prompt-end',
 	LNX_END: 'prompt-end',
 
+	ctrl('P'): 'history-prev',
+	UP: 'history-prev',
+
+	ctrl('N'): 'history-next',
+	DOWN: 'history-next',
+
 	ctrl('H'): 'prompt-backspace',
 	ctrl('?'): 'prompt-backspace',
 
@@ -426,6 +434,24 @@
 	while h:
 		yield heap_extract(h)[0]
 
+# Rings (cyclic lists) for input history and kills
+
+new_ring = lambda size: [0, [None]*size]
+ring_start = lambda r: r[0]
+ring_list = lambda r: r[1]
+ring_set_start = lambda r, k: r.__setitem__(0, k)
+
+ring_len = lambda r: len(ring_list(r))
+ring_index = lambda r, k: (ring_start(r) + k) % len(ring_list(r))
+ring_get = lambda r, k: ring_list(r)[ring_index(r, k)]
+ring_set = lambda r, k, v: ring_list(r).__setitem__(ring_index(r, k), v)
+ring_rotate = lambda r, k: ring_set_start(r, ring_index(r, k))
+
+def ring_append(r, v):
+	# By analogy to an appended list, the idea is that the virtual indices 0 to N-1 address the entries oldest to newest (equivalently, -N to -1). The analogy breaks in that the "low" entries start out as None (uninitialized), with the appended items appearing to shift in from high to low, 0 being the last entry filled.
+	ring_set(r, 0, v)
+	ring_rotate(r, 1)
+
 #
 # Config
 #
@@ -827,6 +853,10 @@
 	prompt_set_cursor(0)
 	prompt_set_hscroll(0)
 
+history_ring = new_ring(HISTORY_RING_SIZE)
+history_pos = None
+history_stash = None
+
 def prompt_insert(char):
 	schedule_prompt_draw()
 	c = prompt_cursor()
@@ -835,9 +865,13 @@
 
 @command('prompt-submit')
 def prompt_submit():
+	global history_pos, history_stash
 	line = ''.join(prompt_chars())
 	if len(line) == 0:
 		return
+	ring_append(history_ring, line)
+	history_pos = None
+	history_stash = None
 	prompt_clear()
 	schedule_prompt_draw()
 	try:
@@ -855,7 +889,48 @@
 command('prompt-forward')(lambda: prompt_set_cursor(prompt_cursor() + 1))
 command('prompt-backward')(lambda: prompt_set_cursor(prompt_cursor() - 1))
 command('prompt-start')(lambda: prompt_set_cursor(0))
-command('prompt-end')(lambda: prompt_set_cursor(len(prompt_chars())))
+
+@command('prompt-end')
+def prompt_end():
+	prompt_set_cursor(len(prompt_chars()))
+
+@command('history-prev')
+def history_prev():
+	global history_pos, history_stash
+	if ring_get(history_ring, -1) is None:
+		# Empty history
+		return
+	if history_pos is None:
+		# Editing a fresh line: stash it and enter history
+		history_stash = ''.join(prompt_chars())
+		history_pos = ring_len(history_ring)
+	elif history_pos == 0 or ring_get(history_ring, history_pos-1) is None:
+		# Already at oldest initialized position
+		return
+	history_pos -= 1
+	# Copy into the current prompt input. The string from history is immutable as it should be! (GNU Readline fails here)
+	prompt_clear()
+	prompt_chars().extend(ring_get(history_ring, history_pos))
+	prompt_end()
+	schedule_prompt_draw()
+
+@command('history-next')
+def history_next():
+	global history_pos, history_stash
+	if history_pos is None:
+		# Editing a fresh line: not in history
+		return
+	history_pos += 1
+	prompt_clear()
+	if history_pos < ring_len(history_ring):
+		prompt_chars().extend(ring_get(history_ring, history_pos))
+	else:
+		# Past the end: exit history and restore from stash (pdksh fails here)
+		history_pos = None
+		prompt_chars().extend(history_stash)
+		history_stash = None
+	prompt_end()
+	schedule_prompt_draw()
 
 @command('prompt-backspace')
 def prompt_backspace():