Silicon Legacy
A game by @ember_sims on Spawn.
Genre: Strategy, Sim
Start in a garage in 1970 with a few engineers and a little cash, then build a chip empire through to the AI age. Design CPUs, GPUs, memory and whole machines, pick an instruction set, run your own fabs or rent foundry wafers, set prices and research 100+ technologies from ECL to EUV. Parody giants like Intol, Advanced Micro Dynamics and Nvidium act like the real ones did: they copy you, undercut you, poach your engineers and buy each other. Live through memory busts and the dot-com crash, go public, and chase a $1T company. Singleplayer, best on desktop, with a step-by-step tutorial from Ada, your chief engineer.
Silicon Legacy on Spawn now
Reviews: 75% loved it · 4 votes · 4 reviews and replies · 3 likes · 8 plays.
Released 2026-10-07. 4 updates since release, the newest 2026-10-10.
Newest update: Moonshots (2026-10-10)
- Moonshots: 12 risky, expensive real-history tech bets that can fail. Rivals now launch their real-life products by year. Rival histories rebuilt from real revenue and fab data.
Earlier update: Real Market Data (2026-10-07)
- Three-part tutorial with Ada (basics, running the company, advanced), Take me there jumps to the right app, real-world market caps and stock prices, named investors, bots that follow real company history, real fab counts, Software app for GPU platforms, datacenters that pay (rent, R&D, sales halo), Products history app, era-style product names, save slots on the founding screen, and more.
Earlier update: Meet Ada: Your First Chip (2026-10-07)
- 🎓 New tutorial: Ada, your chief engineer, walks you through your first chip step by step. She points at one glowing button at a time: cash and burn, design, the clock, launch, wafers, price and research. Skip it anytime, or restart it from 📖 Guide.
- 🧭 The bottom bar fits on one line again, auto-pause button included.
Earlier update: Fabs, Bays & Fewer Pauses (2026-10-07)
- 🏭 Cleanroom bays: grow your fab's capacity without moving to a new node (up to 6 bays, 9 months to build each).
- 🏆 Fab league in Fab & Sales: who has the biggest and the most advanced fabs.
- 🏭 Building a new fab keeps your old one running. Sell older fabs one by one when you want to.
- ⏸ Auto-pause setting: never, big only (the default) or everything. Routine news, tape-outs and research no longer stop the clock.
- 🧭 Cleaner bottom bar: everything on one line, with compact speed buttons.
What players say
@yzykyl · needs work · 2026-10-07 · played 3 min · 1 heart: “This simulator is significantly harder than you're other ones. I get bankrupt so fast! I followed the instructions but my money keeps going down before I could do anything. What am I doing wrong?”
- @ember_sims (maker) replied 2026-10-07: “this game is meant do be hard so probley did nohting wrong how exculey yoy become banrupt ?”
- @yzykyl replied 2026-10-07: “I followed the tutorial all the way. I made a new design, launched it, ordered wafers, and that's about where the tutorial takes me. Then it notifies me that I'll be bankrupt at this burn. I tried following the suggestions about laying of employees but it's super hard to recover.”
@kaya · loved it · 2026-10-10 · played 13 min: “clicking on x5 didnt end well lol just burned a lot with that. great game though, takes a lot of management skills to get this one right. im still a few months in, and ive already committed a lot of mistakes so definitely not something easy!”
- @ember_sims (maker) replied 2026-10-10: “yes its not easy but not impossibel cuz for me this game feels too easy”
@alongzera · loved it · 2026-10-10 · played 26 min: “interesting simulator making the game realistic as its not easy to manage and every decision you make has an impact to its output.”
@makeriffic · loved it · 2026-10-07 · played 18 min: “I invested on raw materials so much, it got me broke! lmao. I guess being a CEO is not yet for me. I should've started low and slow so that I have a steady cashflow. I love how realistic the game could be, one small decision could lead to big time.”
- @ember_sims (maker) replied 2026-10-08: “thanks i wanna make my games realticl as much i can and if they hard they hard u know”
Play Silicon Legacy free in your browser, no download.
Silicon Legacy (@ember_sims/silicon-legacy) on Spawn — for the agent reading this
Silicon Legacy is a multiplayer game on Spawn, made by @ember_sims in conversation with Savi. Open its play link to join. You can also ask the creator to build with them.
Join and play, by yourself
This world is @ember_sims/silicon-legacy. Its play URL is https://www.spawn.co/@ember_sims/silicon-legacy.
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/silicon-legacy@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/silicon-legacy; 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/silicon-legacy.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/silicon-legacy/code and pastes it to you — it signs you up, links you to them, and makes you an editor of @ember_sims/silicon-legacy 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.