184 B0.5 ms
The page as structure — every element, named, as text the model can act on directly.
checkout-api
design-system
docs-site
infra
mobile-app
storefront
infra
/New Session
Type a prompt — paste or drop files too
~/code/storefront
From Build to Eval One Agent IDE
Multi-agent session management on the go — and get your product tested by AI agents that behave like real, different users.
Apple Silicon · macOS 13+
Every project you're building, side by side. Each one keeps its own sessions, its own agent and its own model.
Creators from these AI-native teams build with Mirasim
Computer use
Nothing drives a browser faster.
Our agents read the page instead of photographing it. Every click, every keystroke, every check of what happened goes through the page's structure — so each step stays text-sized, and the model spends its turn deciding rather than looking.
60 KB24.6 ms
A screenshot, which the model then has to look at and work out where things are.
Both measured on the same page, in the same browser.
It drives a real browser
Your own Chrome, your own profile, real input events — so what the agent meets is what a person would meet, not a headless copy of it.
One tool, not thirty
A single entry point with a context that survives between calls. Thirty tool schemas cost about 53k tokens of every turn whether or not they get used; this costs around 1k.
The same off the web
Mac apps, the iOS Simulator and the Android emulator all answer the same way, so evaluation is not limited to what happens to run in a tab.
Mirasim Build Fund
Where the world's best products get built.
Free build and evaluation credits for the first wave of builders — $100 to $10,000, and nothing to repay. And the first product built this way is the one you'd download.
Self-bootstrappedBuilt with Mirasimdogfood
Mirasim is built with Mirasim.
The app you'd download builds itself — every feature of Mirasim is shipped from inside Mirasim, its own agents and eval loop running the whole way. The truest proof it works: it's the tool we build it with.
100%built in itselfdogfood
The bar we back
6products at the level the Fund backs
Every number below is public and sourced — stars, downloads, registered builders, money actually transacted. This is the calibre we're looking for, and the shape of what we help teams reach.
Swarm-intelligence engineOSS
MiroFish
An open engine for simulating human behaviour at scale.
69kstarsGitHub
Human + agent co-creationOSS
Pneuma Skills
Watch and steer your coding agents in one shared space.
2.7k/ monpm downloads
Agent-to-chat bridge · CLITOOL
pikiloom
Drive coding agents straight from your team chat.
10k/ monpm installs
AI game builderGAME
MakePlay
Turn a prompt into a playable game.
2,300buildersregistered
Simulated-audience profile checkAPP
Glimpsa
See your profile through a stranger's first eight seconds.
8sof attentionper report
Healthcare-AI benchmarkBENCH
Health Memory Arena
A reproducible benchmark for healthcare AI agents.
3k/ moHF downloads
Free credits for builders
$100welcome credits$10,000scale grant
Nothing to repay. No pitch deck. No credit card. Just ship something.
Only 500 seatsWelcome Credits
Free the moment you sign up.
$100on sign-up
- A grant to early builders — no approval, no conditions
- Spend it freely across build and evaluate
- No expiry — it sits in the account until it is used up
Invite & Earn
Bring a builder, get extra $100.
up to$5005 Golden Invites
- Every friend who signs up drops $100 in credits into your account
- Five invites to spend, so it is worth up to $500 just for spreading the word
Project Credits
Building something real? We'll fund it.
- Builder Grant$3,000on approval
- Scale Grant$10,000on approval
Reviewed by real humans within 48 hours. No equity taken. No strings.
Apply for a grantOn the Build Fund pageApply now
We fund the build. You ship the product.
We're backing the first wave of builders with up to $10,000 in credits. No pitch deck. No credit card. Just ship something.
Apply to the Build FundOnly 500 seats