Slingshot Speeders v0.1.3 is up on https://slingshotspeeders.com/. Play in the browser. No install.

Home

• Home is MENU plus Sign in with Google. Account, standings, FAQ, and the rest live on their own pages.
• Sign in with Google sits on home next to HOW TO PLAY. YOUR RUNS follows that account.
• YOUR RUNS has SIGN OUT when you are signed in.
• Signed-in pilots get a public profile (/u/…) with rating, Season Alpha points, Trefoil Elo, and Watch links.
• Profile links are a short code, not a row number. Gold names like /u/james stay.
• Public profile names homemade maps, shows career totals (distance, Δv, time, maps won), and paints an alpha supporter gold name.
• Profile and Usage plot each stat on its own chart — distance, Δv, time, plays, and wins, not stacked on one graph.
• Home ALPHA SUPPORTER COMMUNITY MAPS is open whether you are signed in or not. MapMake stays for signed-in alpha supporters.
• MapMake has one HOME. The ship HUD (speed, Δv, chips) only shows when you PLAY the draft.
• STANDINGS is Season Alpha: championship points from SCORE / TIME / Δv, and a separate Trefoil Elo. It resets when Season 0 starts.
• Home maps are Easy, then Medium, then Hard. Temple is Medium. Rendezvous is last (Hard).
• Prime is the beginner map: two small wells side by side. Start clockwise on the left; capture the green ring on the right.
• Temple no longer has a New! mark.
• MENU closes when you click off it.
• MENU Sign out sits at the bottom when you are signed in. Hover stays inside the panel.
• MENU has Race standard — the Stock ship every public board uses.
• Signed in? PLAY uses your name. No YOUR NAME prompt. Alpha supporter names are gold on SCORE / TIME / Δv.
• SCORE and TIME numbers are white, so gold names stand out.
• SCORE / TIME / Δv headers are white with a border when selected — not gold.
• 1 flying is white, in a small outline next to the map name.
• Profile tabs switch — Maps, History, Trefoil, Share.
• Copy link lives on Share. Sign out is in Menu. Alpha supporter is a gold badge next to the name. The round portrait is the trefoil.
• FAQ answers how Season Alpha ranks work — championship points, the 0–1000 rating, and Trefoil Elo.

Play

• A 3 · 2 · 1 counts you in before the ship moves. The clock and the tape start when it hits zero. Restart is a quick 1.
• Official runs save after the 3-2-1 — Orion and the rest.
• Other pilots flying the same map show up beside you, dimmed. They cannot push you or crash you, and your run is still your own.
• Empty tank is not a lose. You keep coasting. Crash or the 10-minute cap still ends the run. On Trefoil you can burn the last of the tank and glide over the line.
• Trefoil fastest only lists real finishes. A crash is not 0s.
• Trefoil RECENT / FASTEST turn white with a border when selected.
• Every map has a JOIN card now, and home shows how many pilots are on each one.
• Home map names say 1 flying when someone is on that map — not a missing-font box.
• Spectate: SHIP / WORLD / FREE at the bottom, and LOBBY opens the JOIN card so you can fly or watch again without going home.
• Homemade maps capture a closed orbit in the green ring, same as Orion.
• Capture needs a full loop inside the green ring. A nearby well yanking you out the other side does not count.
• A closed orbit inside the green ring is a win even if another well would tug it later.
• A win on a homemade map shows up on that map's SCORE / TIME / Δv so you can watch it.
• Homemade maps with moving wells start those wells in the same place every play.

Ship

• Kill-rot dumps spin faster and stops clean. It no longer crawls at the end.
• RCS and Q/E jets shoot out the way they push, same white exhaust as the main engine.
• The stock ship leaves a white exhaust trail when you burn the main engine.
• Main-engine smoke is left behind the ship and fades, not stuck to the tail.
• Main-engine exhaust is smoke left behind the ship — no tail flame.
• Main-engine smoke is a wider plume and hangs a bit longer.
• Afterburn throws a bigger, faster jet than regular main. Exhaust puffs are finer and shoot out quicker.
• 5 hides the trajectory line. Same control in Watch. 4 is still arrows.
• The trajectory line is back in play. 5 still hides it.
• Every well now draws a faint outer circle: that is how far its gravity reaches before it fades to nothing. The ring is quieter so it does not shout over the well.

Watch

• After rewind hits the start, 1x plays again. You do not have to tap PLAY.
• Afterburn marks on the flown path are twice as long as regular burns.
• A gold name on Watch opens that alpha supporter's profile.
• That name is a light gold chip with dark gold type — not a green SHARE button.
• Links open the tape without flashing home first.
• [ at 1x rewinds. Speed goes -1x, -2x, and so on. SHIP / WORLD / FREE sit under play with PATH.
• Path rotate marks match live Q/E, and the arrow heads are larger.
• Rotate icons on the flown path follow Q and E.
• Pink and red burn arrows point the way you thrust, not along the flown path.
• Burn arrows are longer, thinner darts, spaced out along a held burn instead of stacking up.
• Time slider: grab the dot.
• Rewind (|<<) jumps to the start of the tape. << / >> still skip 5 s.
• Scrubbing lands on the time you dragged to, and the transport bar is wider so the slider has room.

MapMake

• Drag a well's edge to resize it. Bigger wells pull harder and reach further — twice the radius is four times the pull. Grab the middle to move it, the rim to resize it. Pushers and moving wells work the same way.
• The trajectory line follows a moving N-body the same way it does on Planet & Moon.
• Park a closed orbit in the green ring to win. The circle does not have to sit exactly on the well.
• Drag the start pad to move it. Drag the gold stick to set heading and speed.
• Drag an N-body's gold stick to set its starting speed.
• Deleting a moving well takes it off the map.

Alpha supporter maps

• The community shelf is Alpha Supporter Community Maps. The $10 pack is alpha supporters.
• Supporter Community Maps is the shelf of maps from supporters. Cards say who saved them and when.
• Alpha Supporter Community Maps has NEW MAP.
• SUBMIT a community map asks you to name it (20 characters). Recent runs and profiles show that name, not HOMEMADE.
• SUBMIT locks a community map. You cannot change that version. COPY opens a new draft from it. Three submitted maps max.
• Each supporter community map has its own SCORE / TIME / Δv under PLAY and EDIT. Click a row to watch that tape.
• Community map thumbnails sit on the start pad.

https://slingshotspeeders.com/

PLAY FOR FREE, IN BROWSER, NO ACCOUNT REQUIRED. 2d top down first orbital racing game, competitive speed runs.

Good race!

v0.1.2 is live. Inverse-square gravity, one Stock ship, public boards. This update changes how the ship flies, so the live lists are empty and you are racing a new physics.

Boards wiped

SCORE / TIME / Δv and Trefoil start over. Old times were flown on a constant-mass hull. They are not comparable to a ship that gets sharper as the tank goes.

The pre-alpha lists are on the Pre-Alpha Archive. Names and times stay there. The pre-alpha database is backed up.

The ship is half fuel

Half the hull is propellant. Thrust force stays the same. Burn it off and you accelerate twice as hard, and the nose comes around twice as fast. The last burns of a run are the sharpest.

The HUD tank is Δv — how much speed change is left. Empty still says OUT OF FUEL. A full tank is about 234 m/s. There is no refuel. Dumping early to get light also throws away the Δv you needed to use that pace.

Sip still beats dump on mixed score. Time and a full tank weigh the same. Burn low still wins (Oberth).

The gold thrust arrow grows with how hard you are actually accelerating — empty tank or afterburn. Dry afterburn is twice the dart of a full-tank main.

Temple

New Hard map. Two wells. Time the sliding door, then slip through rotating spokes into the green ring on the right. Capture is a closed orbit there. The spokes still kill if they hit you in the ring. You start in a tight, fast orbit around the first well.

Chaos is retired (too close to Asteroids). Asteroids sits under Orion, wider capture ring, no stray well out to the left of the start.

Watch one run. VIEW the field.

Click a row and you watch that tape: purple when slow, light orange when fast, pink thrust ticks (red on afterburn), yellow rotate marks where you yawed. PATH (or P) hides the flown line and the marks. The trajectory line stays.

Home VIEW next to PLAY opens the map with every stored run line. That is the density view. Replays stay clean.

Flying the HUD

Q/E are two small yellow arrows at the nose and tail, like RCS jets. Counter-clockwise: nose left, tail right. They ease in like the gold thrust arrow. Kill-rot shows the same couple while it is braking; they shrink with the live torque and ease out as the spin dies.

The trajectory line holds if you almost stop and fall back. Rotating does not flicker it. A WASD burn still redraws.

Crash is a red CRASH card, same as OUT OF FUEL. R tries again. HOME is a button in play and Watch; Esc still leaves. SHARE copies one watch link (?r= or ?race=). Solo and sandbox time out at 10 minutes. Trefoil is still 5.

Also

FAQ says scored runs are public, the tank follows the rocket equation, and inverse-square in words. Home ROADMAP is stretch goals (community maps, ship classes, a $10 supporter pack). Not this cycle.

Devlog: https://www.youtube.com/@SlingshotSpeed

Play: https://slingshotspeeders.com/

Can you tell what this is?

This is a notice to record any past runs you may want to hold on to. This next version will involve fundamental changes to the way acceleration works, given the rocket equation, and how less fuel in your ship means less mass, thus more acceleration. Along with the afterburner, this should result in highly strategic fuel usage and longevity to the fundamental architecture given that it is true to physics.

The tightness of the green win circle really determines a lot of the difficulty. Getting inside a really thin orbit is much harder. This should probably be Medium instead of Easy.

Points for style

Slingshot Speeders | The First Orbital Racing Game

Inverse-square n-body gravity. Force-based ship. Slingshots. Capture a closed orbit. Public SCORE / TIME / FUEL boards. Server owns the race: you send button presses, not position or time.

Play (v0.1.1): https://slingshotspeeders.com/

FAQ: https://slingshotspeeders.com/faq

Changelog: https://slingshotspeeders.com/changelog

v0.1.1

Orion (was Easy) sits at the top of home. Green Easy tag. Recommended for beginners in green on the title line. Start in circular orbit at the left well, one mass in the middle, capture a wide ring at the right.

Trefoil sits under Orion. Maps now carry Easy / Medium / Hard tags (green / yellow / red outline). Asteroids is Easy. Rendezvous is Hard. Everyone else is Medium. New! sits on the title line, left of the tag.

FAQ (top left) — n-body vs 2-body, scoring, and the first-orbital-racing claim: https://slingshotspeeders.com/faq

Trajectory line samples at 60 Hz with no fade. A burn redraws it immediately. A coast reuses the last solve until the next 60 Hz tick. Each sample folds three sim ticks, so it is not a 165 Hz re-run of the scored flight.

Also in this build:

• Home type is Zector (title and HUD).
• Type is a bit larger on home, HUD, and the public pages.
• Subtitle: The first orbital racing game (no period).
• PLAY name box stays one size while you type.
• Recent runs drop DIST and SPEED so WHEN fits on one line.
• Opening FAQ / WHAT'S NEW / USAGE no longer leaves home stuck drag-scrolling when you come back to the tab.
• Loading screen says LOADING, centered.

Still there: Trio, Snake, Elevator, Rendezvous, Asteroids, Planet & Moon, Chaos, Slingshot, Trefoil.

Browser. WASD thrust, Q/E rotate, click a body to pin the trajectory line.

Slingshot Speeders is a free 2D orbital racer in the browser. Inverse-square gravity (same falloff as the solar system). Force-based ship. Slingshots. Capture a closed orbit. Public SCORE / TIME / FUEL boards. Server owns the race: you send button presses, not position or time.

Play: https://slingshotspeeders.com/ Test: https://test.slingshotspeeders.com/ Usage: https://slingshotspeeders.com/usage Changelog: https://slingshotspeeders.com/changelog

v0.1.0 — first stable production build (2026-08-21). Live stays tagged. New work goes through test, then a promote. Production boards stay; we do not edit the live game in place.

Maps

Trio (gold New!) — three Rendezvous-size free-moving pullers. They tug on each other. Start in a low orbit around one. Hop and park a closed orbit on another. Empty boards.

Snake (gold New!) — short sideways S, about nine wells, tips flared so the bends are not hairpins. Fly left → right. Static pull along the path, moons on mixed-radius rails, moving pushers (first map that ships push wells). Capture the green ring on the last well. Empty boards.

Still there: Easy, Asteroid Field, Planet & Moon, Chaos, Slingshot, Elevator, Rendezvous, Trefoil (online race).

Play

• One fuel tank. RCS at half thrust costs half as much.
• Pull wells/moons: arrows in. Pushers: arrows out.
• Home subtitle: The first orbital racing game.
• Arcade pixel type (Kenney Mini Square, CC0). Same width every letter. Home, HUD, WHAT'S NEW, USAGE, name box.
• STRESS TEST is gone from home.

Watch

• The white trajectory is the one recorded during the run. Watch does not re-solve a second path.
• Same ribbon as live: no hitch, no hole behind the ship.
• Live coast line refreshes twice a second so it stays with the ship even when you are not thrusting.
• Recent runs open in Watch again, including tapes from the two-tank era.
• Win card shows time and fuel right away. Score waits for the logged board number.

Usage

• USAGE opens a real page (/usage), not an in-game graph.
• Four live charts: visits, plays, fuel, distance.

Under the hood (this is the stable cut)

• Gravity and win/crash/fuel rules live in one shared sim. Client and server cannot disagree about gravity.
• Score lists are not silently rewritten on every boot (migration is gated). One owner for run outcome.
• License audit: proprietary game (Masland Tech LLC). 457 linked crates checked. Zero copyleft. Third-party notices shipped. Fira Mono (OFL) replaced with Kenney Mini Square (CC0).
• Test and production are two sites on the same machine: different port, wasm, and database. Production sqlite is never overwritten by test. Test is noindex.

Future orbitmap

• Map making — drop gravity wells, set start position and velocity, fly the map you just built.
• Teleportation — pads that jump you across the field without breaking the orbit game.
• Weekly challenges — a rotating scored objective, fresh boards each week.
• New race track — a second online-race layout (not only Trefoil).
• Ship classes — different hulls with different thrust / tank / handling. Same gravity.
• Kessler Run — new map. Debris field. Thread it. Capture on the other side.

On my client side I won, but the server detected a collision. The snake map turns out to be an amazing way to test this.

Slingshot Speeders v0.0.9 is live

Play: slingshotspeeders.com

The first orbital mechanics racing game. Free in the browser. Real inverse-square gravity. You fly. The server scores.

• Talk: r/SlingshotSpeeders · Lemmy
• Full notes: slingshotspeeders.com/changelog

Elevator (New Map)

• Location: Sits at the top of home with a gold New! mark.
• Objective: Start in orbit around the lower well, ride a rising well on the side rails, and capture a tight closed orbit in the green ring around the top well.
• Mechanics: Rail wells slow, reverse, and shuttle continuously (they don't vanish or get stuck at the top).
• Win Condition: Must maintain a bound orbit around the top well, inside the green ring and outside the crash core. A wide loop that only clips the ring does not count.
• Leaderboards: SCORE / TIME / FUEL start empty. Old runs on this map were wiped.

Mobile & Tablet Support

• Dedicated Touch HUD: Native layout instead of a squished desktop interface.

• Left Thumb: On-screen Q W E / A S D (hold).

• Right Thumb: SHIP / WORLD / FREE, MAIN / RCS, KILL / BURN (tap).

• Telemetry: Slim strip along the top to keep the field clear.

• Desktop Unchanged: Same keyboard controls, dense bottom card, and chips.

• Input Fixes: Typing now stays in the name field without boards jumping or stealing focus. PLAY properly opens the OS keyboard on mobile.

Replays & Tapes

• Persistent Live Rooms: Rooms stay up after a run finishes with full playback controls (pause, skip, speed, drag timeline).

• Playback Mechanics:

• R jumps directly to the start.

• End of tape freezes on the last pose (no auto-loop).

• Speed selection range: 1x–100x.

• Path Rendering: Replays draw the exact white path recorded while flying (does not re-solve gravity on watch, accurately showing curves around moving wells up to 100×).

• Trefoil Updates:

• Click any ship to track that racer's white path.

• ALL mode displays every stored path simultaneously.

• Race start delay reduced from 15 seconds to 10 seconds.

Leaderboards & UI

• Timestamps: SCORE, TIME, and FUEL lists now display WHEN (matching Trefoil timestamps).
• Name Visibility: Ship names now stay readable when zoomed in, sitting above the hull without obscuring the field.

Rendezvous Map Updates

• Velocity Visualizer: The green arrow shows relative velocity to the moving ring (stretches/shrinks as you match speed).
• Trajectory Line: Dotted purple line illustrates the moving ring's orbital path.
• Win Condition: Hold position inside the moving ring for 5 seconds.

Performance & Engine

• Smoother Stress Tests: Faster WebAssembly gravity calculations in-browser. Desktop lab can now utilize extra CPU cores for moon simulations.
• Multithreading: Capture, free play, and Trefoil run on dedicated simulation threads to keep the UI responsive.
• Server Authority: Wins, tapes, and positions remain strictly server-verified (client sends button presses only).

Play: slingshotspeeders.com

Hopefully the purple orbit makes it a bit easier to match your orbit and adjust it. Probably going to be one of the hardest challenges in the game, but also one of the most rewarding!

As far as past recordings go and the leaderboard, they will have to be wiped given the way recordings worked previously they didn't save their current state variables. So just a reminder this is an experimental pre-alpha test build!

Slingshot Speeders v0.0.8 is live

Play: https://slingshotspeeders.com/

The first orbital mechanics racing game.

Talk:

• Reddit: https://www.reddit.com/r/SlingshotSpeeders/
• Lemmy: https://lemmy.world/c/SlingshotSpeeders

Full notes: https://slingshotspeeders.com/changelog

Rendezvous (hard mode)

Rendezvous is the new map. It sits at the top of home with a gold New! mark.

Two equal-mass bodies orbit each other. You start around one. The win is not a closed orbit around a well. You have to match the moving green ring in orbit around the other body and hold it for 5 seconds.

This is the hard mode for anyone who understands orbital mechanics. Matching position is not enough. You have to match the moving ring's velocity too.

• A green arrow on the ship is your velocity relative to that moving ring. Burn along it to match. It shrinks as you match. Cyan is still velocity relative to the body you clicked (the pin).
• Hold time sits at the top of the screen.
• Click a body and the white coast still pins to that frame. There is no grey predicted moon orbit anymore.

If you know Hohmann transfers, phase angles, and matching a target in a different orbit, this map is for you.

Boards

Scored maps now have three lists of the same wins:

• SCORE (mixed: time and leftover fuel still weigh the same)
• TIME (fastest)
• FUEL (least burned)

Fuel on the board is main tank seconds + RCS seconds. One second of either still counts as one second.

Trefoil stays a race card: RECENT races (default) or FASTEST times, same card.

Slingshot is no longer marked new.

Share and talk

SHARE copies the URL only. Paste is the link, not a score sentence.

• Win a map: SHARE is the tape (?r=). Fast wins keep a tape too.
• Watch a tape: SHARE copies that same tape link. The button flashes when you click it.
• Watch a Trefoil race: SHARE copies a link that opens that race (?race=).
• Open a shared link, then hit Esc: you are on the site. Refresh stays on home. It does not reopen the tape.

The win card is SHARE only (score and time). The extra rank sentence is gone. Talk belongs on Reddit or Lemmy, not as an in-game note.

SOCIAL (top-left) opens the Reddit and Lemmy links.

HOW TO PLAY now includes the game idea at the end.

Sharing the site itself (Discord, chats, link previews) leads with The first orbital racing game. then a short free 2D space race description, with the icon.

Flying

• FREE CAM: click-drag to look around. Toggle with the 1 key or by clicking the HUD.
• The white coast is the real 50 ms forecast, live and on watch. Only the switch between samples eases.
• A path that crosses itself (Trefoil) no longer blanks when you fly through it.
• Passing in front of the trajectory line no longer cuts it off.
• Replay uses the same trajectory line as live play.
• Clicking a body no longer draws a grey predicted orbit. The white coast still pins to that body.

We will not predict the path of gravitational bodies. Only player ships get a prediction path.

Race

Trefoil no longer kicks you for flooding when you race.

SHARE while watching a race copies a link that opens that race.

Stress lab and sim

Home STRESS TEST is one dense field: a thousand wells, a thousand moons, and cyan rings that shove you away. No score.

Lab moons yank each other. Orange moons pull (minus). Purple moons shove (plus). Rings show + or −.

A slam through a well stays smooth. Thousands of wells and moons still feel smooth.

The sim runs at 165 updates a second. Old tapes still play at the rate they were recorded.

Home

• WHAT'S NEW opens the changelog page.
• Home cards scroll inside the card. The page behind them stays put.
• PLAY asks for your name, then starts that map.
• Version sits with ping so the title can stay centered.
• The line under the title is The first orbital mechanics racing game.

What's next

The next major focus is a touch-screen mobile control UI.

That is a completely separate interface from the computer / keyboard experience. Same game, same physics, same net. Desktop stays keyboard and a dense HUD. Phones and tablets get big tap targets and on-screen thrust, rotate, and afterburn.

Not a squeezed copy of the desktop HUD.

Play: https://slingshotspeeders.com/

It's official, the game now has mobile touch screen support. The UI will be refined over time to be more user friendly and intuitive, but currently it's in a functional state such that you can win through your phone.