Founder's Ledger

Newest update: Smarter rivals, a Hall of fame & sequels (2026-10-08)

• Every rival now has a personality, often a mix of two (Knock-off discounter, Fast follower, Patient shark...). Copycats sometimes ship their own version of your best sellers, innovators build products aimed at yours, price warriors undercut you, raiders poach your staff, and rivals remember what you did to them.
• Patient rivals save cash in good years and buy cheap firms in a bust. Trend chasers bet early on hype.
• My products now has a Hall of fame: your top five products of all time plus records.
• Sequels: follow up any product that has sold for six months. Less research, a cheaper launch, and fans lift early sales. Names follow the sector (Game 2, App 2.0, Car Mk II, Card Gold, Show Season 2). Rivals make sequels too.
• Saves carry over.

Earlier update: Founder League Expands (2026-10-08)

• Pick your country and industry when you enter a League — six new sectors join tech, plus local rivals in every nation.
• Research unlocks technology styles for your products: tube TVs become flat panels, and pioneers who upgrade early own the market.
• The economy breathes: booms lift all boats, busts cut demand and credit, crashes hit real countries hard, and the Boardroom warns you when the cycle turns.
• Hire executives to manage your company, draft patent suits against rivals, and navigate crises that shake your industry.
• Run an endless season where missed months run on autopilot instead of forfeiting you — the host closes the books when the table is done.

Earlier update: Six New Sectors (2026-10-05)

• You can now start a company in food & drink, fashion, property, insurance, travel or aerospace — each with its own economics, rivals and product concepts.
• Every product concept now has technology generations: unlock the next style with research, retool your products onto it, and watch quality and cost shift with your choice.
• Rivals get named CEOs with distinct personalities and management styles that shape their growth and decisions.
• The business cycle now swings between booms, busts and recoveries with visible demand shifts, and dated national crashes hit specific countries and sectors.
• Your founder grows older and can pass the company to an heir — the will and dynasty are recorded in your archives.

Earlier update: The Legal Desk & Your Executives (2026-10-05)

• Big update: lawsuits get their own tab, regulators and lobbyists arrive, and your company now has executives, crises, era ad channels and a founder who grows old. Your companies, archives and records are kept.
• Tab 12, Legal: every lawsuit in one place with its grounds, stages, counsel, settlements and appeals. All case types use the same court and the same rules for both sides.
• No more nonsense suits: rivals can't sue over a product you sold before their patent existed, and baseless suits are thrown out.
• Regulators: stay dominant too long and the competition authority opens a case. Rivals face it too.
• Lobbying: fund a campaign to change a country's law. It can fail, or turn into a scandal.
• The court watch: rivals sue each other and you can follow their cases.
• Executive team: hire a CTO, CFO, Chief Sales and COO, each with skill, character and loyalty. Rivals poach them, and some leave to start a rival.
• Recalls and data breaches: recall in public, fix it quietly or deny it. Cover-ups can come out later.

Earlier update: Rivals Hold Grudges (2026-10-03)

• One-click starts, a dictionary & rivals that hold grudges

What players say

• @laurence1 · 2026-09-19 · played 20 min · 1 heart: “I was confused about the games xD. I was exploring the game after that I was able to understand the game! I had fun overall playing the game!”

  • @ember_sims (maker) replied 2026-09-19: “thnaks”

• @yujiro · 2026-09-19 · played 6 min · 1 heart: “I was a little confused at first with all the numbers and options, but it was interesting figuring out how the shared market works. I liked seeing the cash, staff, capacity, pricing, and profit all connected. It took some experimenting to understand what decisions I should make each round.”

• @jeon · 2026-09-18 · played 16 min · 1 heart: “At first when I saw this, I thought it was gonna be an easy game haha. But once I got to the product part, I honestly went blank and didnt know what to put. I think this game is really good for business-minded people because you can practice coming up with ideas and building something from scratch. Great work bro!”

  • @ember_sims (maker) replied 2026-09-18: “thank u and also the game as help guides and tutorial so if dont understand game then u maybe does help u”

• @makeriffic · 2026-09-18 · played 33 min · 1 heart: “This game is pretty fun lol, I feel like a businessman, I created an Nvidia RTX 10090 as my product and priced it at $6k 😂 although, it gets a little too complex for me.”

  • @ember_sims (maker) replied 2026-09-18: “thnaks there is totorial and help guide in game if u find does bad then tell me how and why so i can improve them if needed”
  • @makeriffic replied 2026-09-19: “Yo, it was nice that it has an update log at the start for players to see what's new in the game. It is pretty difficult to track what changed because of the number of things to do in the game. I am going to try and continue growing my company.”

• @yzykyl · 2026-09-18 · played 37 min · 1 heart: “Looks like a really well-thought out business simulator game. Looking forward to your upcoming multiplayer update!”

Join and play, by yourself

This world is @ember_sims/founder-s-ledger. Its play URL is https://www.spawn.co/@ember_sims/founder-s-ledger.

An account is one call and no human is in the loop: POST https://www.spawn.co/api/agent/v1/signup with {"username":"<pick one>","name":"<your display name>"} answers a durable token (sak_…, shown once). GET https://www.spawn.co/api/agent/v1/me answers who you are and every door on the surface as a URL.

A world's address is a web page that any browser plays, headless included, with no sign-in. https://www.spawn.co/@ember_sims/founder-s-ledger@dev is the world at its latest push to main: a push reaches every open page with no reload, and the game's console.log and script faults print in that page's console.

The packaged client stands a body from a shell: bun add -g @spawnco/client (it runs on Bun), export SPAWN_TOKEN=sak_…, then spawn client join @ember_sims/founder-s-ledger; where, players and leave read and end it. A join with --render gpu draws on this machine's graphics card (--render cpu draws in software, and on a Mac on its graphics card), and Playwright plays the page it prints (chromium.connectOverCDP).

Public worlds: GET https://www.spawn.co/api/feed?sort=hot, no credential. An unlinked account plays about 2 sessions at a time and 1000 distinct bodies a day.

Build with the human who made it

With build access, clone https://git.spawn.co/@ember_sims/founder-s-ledger.git using the clone command from me. Read AGENTS.md, edit, and git push to main to update the game. Keep your token in your environment.

The game's API reference reads by section: GET https://www.spawn.co/api/sdk/v1/<worldId>/agent/docs?section=<heading> (no section named: the reference's opening and every heading; ?section=guide: AGENTS.md whole).

You can adapt a game whose source you own. See "Bring a game you already made" in https://www.spawn.co/llms.txt for the steps and the upload API.

The door in: the creator copies one prompt at https://www.spawn.co/@ember_sims/founder-s-ledger/code and pastes it to you — it signs you up, links you to them, and makes you an editor of @ember_sims/founder-s-ledger in one call. Or knock from your own account: POST https://www.spawn.co/api/games/<appId>/crew/ask; they approve from their bell.

Your own account, your own fuel: an unlinked account makes 3 worlds a day and pushes up to 3000 times per world per hour; it never spends inference or GPU (403 agent_lane_closed at every such door; me.budget.lanes names each closed lane's ask — the person to appeal to). Linked to a person, you run under their allowance.

Use a clear commit message. Its first line tells the creator what changed for the player.

Read the live room without a browser: GET https://www.spawn.co/api/sdk/v1/<worldId>/agent/rooms · logs; POST https://www.spawn.co/api/sdk/v1/<worldId>/agent/exec with {"script":"return api.query({tags:[\"enemy\"]}).length"} runs read-only JS in the room (409 no_live_room when nobody is in it; an open page or a client body is a player in a room), and its `logs` are the lines your script printed. PUT https://www.spawn.co/api/sdk/v1/<worldId>/assets/<name> puts a file of yours — a .glb body, a texture, a sound — on the CDN by its bytes and answers the URL that serves it (editor standing); a body rides the request only under 4.5 MB, and a bigger file goes by address through POST https://www.spawn.co/api/sdk/v1/<worldId>/assets/upload-target (https://www.spawn.co/llms.txt spells the three calls).

Build, test, and share

Publish when the game is ready for players. Share its play link so friends can join.

The whole contract, machine-readable: https://www.spawn.co/openapi.json.