HANDSHAKE

a love story in 64 hops

You are SYN. You want ACK. Root is the only one who can give it to you.

Design doc: DESIGN.md.

Run it

python3 /Users/johnking/Documents/handshake/serve.py 8123

Then open http://localhost:8123/. Headphones — every frequency in this is the real frequency and half the mechanics are inaudible without them.

serve.py is http.server plus Cache-Control: no-store, because ES modules cache hard and it makes every edit look like it did nothing.

Controls

WASD	move
SPACE	jump / hold 2600 Hz
mouse	look (click to capture; dragging works too)
E	use
M	traceroute — the level select, and where you drop cargo
P	philes — read what you've picked up
`	hop select (dev)
ESC	release the mouse

It saves. Every hop completes a handshake with the world and writes to localStorage; the boot screen offers R — RESUME when there's something to resume.

What's here

Fourteen playable hops, each a different genre, one renderer.

id	hop	what it is
coldboot	1	FP tutorial in a 512-slot NIC ring buffer, then the DMA rips you out
stack	2–8	7-floor descent, one verb per layer: transcode, keep the session, reassemble in sequence, route within a hop budget, listen-before-transmit with real exponential backoff, ride the waveform. Stateful FIREWALL boss
timewait	9	walking sim. beige room, 50 Hz hum, half-open connections in plastic chairs, FIN by the door
war	10–16	EFnet twin-stick. netsplit riding, ops crowns, and a trojan arms race — four weapons the level patches 70 s after you first use one
smash	17–20	2D side-scroll char buf[64]. canary, return address, NOP sled, shellcode — then NX lands and you build a ret2libc chain out of other people's platforms
worm	21–28	Morris worm RTS, 1-in-7 reinfection locked on. An antidote you can release that travels only over live links, while you are killing links
cuckoo	29–34	LBL 1986 terminal. connection time is visibility. you get caught
board	35–44	the BBS, over three days. busy signal, ANSI painting at live baud, ratios, NUP gate, ANSI bomb, the sysop watching you type, FidoNet, playable LORD and Trade Wars — then LAST CALL, and it closes
shell	43–44	kruuna.helsinki.fi, 1991. always on, 38 users at once, talk(1) character by character, the comp.os.minix post, and a kernel compiling in the background while you use the shell
handshake	45–50	five-boss rhythm arena. dial tone → DTMF → ANSam → V.8bis → carrier
copper	51–58	FP through duct, load coils, a Strowger cathedral, a lineman's handset
bluebox	59–63	playable 13-button blue box. 2600, KP/MF/ST, tandem stacking, then SS7
climb	63→1	on-rails reverse ascent, one gate per era testing the verb it taught you. Spectre is a real split screen, plus Rowhammer and Log4Shell
root	64	the room is empty. then the ACK comes back — and on Tuesday, so does your FidoNet message

The three load-bearing ideas

TTL is the health bar and it only goes down. 64 hops, no healing, ever. Levels aren't hard, they're expensive.

Bandwidth is resolution — src/link.js. One render target and one shader. Your baud rate sets the target height; at 1200 and below the scene renders as ASCII glyphs. HS.link.setBaud(0..6) in the console to see it. The V.8bis fight sets this for real.

Every header you drop is a piece of clothing — makeSyn() in src/kit.js. Seven wireframe shells, one per OSI layer, shed as you descend.

MTU

Files taken off the BBS are lore, and lore is paid for in distance. Two is free; after that you don't fit down the next hop in one piece and every hop costs a TTL per extra fragment. You can put things down again from the traceroute map. That's the whole economy: everything worth reading costs you some of the distance you have left.

Retrain

The line doesn't stay the way you negotiated it. Somewhere after hop 51, wherever you happen to be, it degrades and takes a baud rate off you — and the way to claw it back is the ANSam beat from hop 47: SPACE on the phase reversal, 450 ms, four clean ones. Terminal levels opt out with noRetrain: true, because stealing SPACE from someone mid-sentence isn't a mechanic, it's a bug with a story attached.

The philes

All 200 are written, in src/philes.js, and all 200 are findable. Read them with P.

The voice rule is the whole thing: each one is written by somebody, in the year it happened, who did not know they were in a game. Nobody explains anything for the player's benefit and nothing is written in hindsight.

Where they live follows from that. The board is 1991, so the board cannot carry a file about WannaCry — it carries the seven read-online areas (g-philes, the law, the scene, virus, the iron, telephony, unix), and reading is free while downloading costs MTU, which is how a real board worked. Everything after 1992 is on the climb, because the climb is the only level that travels forwards in time: thirty-six years bolted to the shaft wall, going past at speed. You get the file for having been there whether or not you turned your head, and they arrive quietly — thirty-six notifications in fifty seconds is a wall, not a level, so ctx.phile(id, …, quiet) collects them and the count lands once at the top.

node tools/philecheck.mjs — duplicate ids in an object literal overwrite silently, which cost an hour once. It also reports anything written but not placed in a level.

Audio

src/audio.js — every tone is oscillators, nothing is sampled, and every frequency is the real one: 350+440 dial tone, the DTMF matrix, R1 MF pairs with real 100 ms KP / 60 ms digit timing, 2600 Hz, ANSam at 2100 Hz reversing phase every 450 ms, Bell 103 FSK. About 300 lines and zero megabytes.

The score

src/score.js — no level gets a chord somebody picked because it sounded nice. Every bed is derived from a real number belonging to its era:

hop	built from
coldboot / stack	1000 Hz, the reference tone every piece of telecoms test gear agrees on, folded down
timewait	50 Hz mains and its harmonics — the room's own hum is the whole score
war	the 1800 Hz V.32 carrier, folded, with dial-up hiss under it
smash	0x90 — the NOP byte read as 144 Hz, so the sled has a pitch
worm	seven partials, and the seventh one is wrong
cuckoo	45.45 baud, the Model 33 teletype rate, as a clock
board	the 1200 Hz V.22bis carrier, folded four times — the doc's own instruction
shell	the 750 Hz terminal bell over Helsinki's 50 Hz mains
handshake	nothing. The fight is the score and anything under it is noise
copper	20 Hz ringing current, 50 Hz mains, 10 pps Strowger stepping — three real clocks beating against each other
bluebox	the six MF tones. Literally what a blue box contains
climb	all of it at once
root	2600 Hz, folded six times until it is a low room tone, finally at rest

Some come out beautiful and some come out ugly. That's correct — a 1980 exchange wasn't tuned to A=440, and pretending otherwise would be the same lie as setting the ANSI art in a proportional font.

Layout

index.html          shell, all CSS, importmap
serve.py            dev server, no-store
src/main.js         router, TTL, traceroute map, the loop
src/link.js         bandwidth → resolution. the post shader.
src/audio.js        every tone in the game
src/term.js         80x25 cell terminal, pipe colours, CP437 blocks as geometry
src/kit.js          body/collision, camera rigs, SYN, labels, seeded rng
src/input.js        keys, pointer lock, the ANSI bomb's remap table
src/hud.js          status line, subtitles, title cards, NO CARRIER
src/levels/*.js     one file per hop
vendor/             three.js r17x, vendored

Each level exports { id, hop, title, via, baud, mount(ctx), update(dt,t,ctx), unmount(ctx) }. ctx hands it a fresh scene, camera and collision world, plus say/card/hint/phile/ spendTTL/setBaud/next. Genre switches are just different camera + controller modules over one renderer — that's the whole trick.

Dev handles

HS on window: HS.goto(id), HS.link.setBaud(n), HS.game, HS.philes, HS.run(n) — drives n frames by hand, because requestAnimationFrame is throttled to zero in a hidden tab and that makes the game look broken when it's only asleep.

Skipped

• Multiplayer (CHECKSUM) — the Journey-style anonymous pass-by. Needs a server; add when there's something to connect to.
• Playing both fragments — fragmenting costs TTL, it doesn't split you into two packets you alternate between. Add when a level has a corridor narrow enough to need it.
• Levels run 5–12 minutes against a design doc that asks for 5–20. The genres, mechanics and set pieces are all in — the duration is still short. See STAGES.md for a per-hop breakdown of what's in and what's next.