A walkable 3D bank where every desk is a real smart-account operation.
Built in Godot 4.5 for the browser. You do not click “Confirm” in a wallet pop-up — you talk to a teller. Under the floorboards: Bloxchain governed accounts via the public @bloxchain/sdk, Privy session signers, ENSv2 names, and a Uniswap v4 FX desk — live on Sepolia.
For ETHOnline 2026 · Start Fresh.
Live Sepolia captures (2026-09-12).
Most crypto apps hide security behind a wallet modal. Branch Zero makes the security the building.
You are a new customer at the first branch of a bank that runs on public rails. Staff take the rules seriously and explain them cheerfully. Open an account, pay the florist, bounce a large wire into the vault, wait out the clock — or skip cooling with a hand scan at the manager’s desk — and leave with a receipt whose fine print is a block-explorer link.
Tone: Papers, Please procedure + Animal Crossing warmth. On screen, everyday bank language. Protocol jargon only if you Ask why.
Design pillars (see docs/GAME-DESIGN.md):
| Pillar | Meaning |
|---|---|
| Process is the puzzle | Bank procedure is the on-chain workflow. No fake mini-games. |
| No pop-ups, ever | One Privy consent at Account Opening. After that, tellers stamp slips. |
| Honest theatre | Boards, clocks, and balances are read from chain — not local fiction. |
| Small, warm, legible | One building, stylised low-poly cast, web single-thread budget. |
The loop is errand-driven. The greeter (Ash) routes you; each desk is a real lane:
| Desk | Staff | What you do | What the chain does |
|---|---|---|---|
| Account Opening | Iris | Sign in once, consent once | Deploy your AccountBlox; Privy session signer + policy |
| Counter | Eve | Pay an approved payee | Lane A — instant meta-tx (requestAndApproveExecution) |
| Vault | Bob | Wait for the clock, then release | Lane B — time-locked wire; clock is releaseTime |
| Manager | Mr. Walker | Hand-scan Priority, or shred | Skip cooling (meta-approve) or cancel while PENDING |
| Name Desk | Petra | Claim you.branchzero.eth |
ENSv2 subname + passbook text records |
| FX Desk | Johnny | Ask for a rate, swap | Guarded Uniswap v4 — practice USD → EUR | ILS |
Walk without an inbox: http://localhost:5173/?mock=account. Demo storyboard: docs/DEMO-SCRIPT.md.
Branch Zero — Est. Block 0. A branch that treats smart-account security as furniture: rope queues, a departure board of today’s movements, a vault door whose light turns green only when the timelock says so.
| You meet | Role in the story | On-chain identity |
|---|---|---|
| Ash | Greeter — routes your first errands | — |
| Iris | Opens your account; explains the one consent | Bank provisioner |
| Eve | Stamps routine slips at the counter | Broadcaster |
| Bob | Watches the vault clock with you | Timed release path |
| Mr. Walker | Priority or shredder — never a second timed stamp | Branch manager role |
| Petra | Engraves your bank name | ENSv2 registrar |
| Johnny | Quotes and swaps at the FX desk | Guarded Universal Router calls |
Cast and dialogue rules: docs/NPCS.md · World layout: docs/WORLD-3D-ENVIRONMENT.md.
Three runtimes, one contract per player, public packages only.
Browser Server Chain
────── ────── ─────
Godot 4.5 (GDScript, web) Teller Desk (Fastify) Sepolia (Live Main)
└─ never holds keys ├─ Privy session-signer RPC Remote EVM 1337 (Dev Mode)
Vite + React shell ├─ broadcaster hot wallet Arc Testnet (wing — deferred)
└─ window.BranchZero └─ SSE status / receipts
@bloxchain/sdk · viem · Privy
| Layer | Choice | Why |
|---|---|---|
| Game | Godot 4.5.x · GDScript · single-thread WebGL2 | Walkable bank in the browser; no C# on web export |
| Shell | Vite · TypeScript · React overlay | One Privy modal; canvas focus after overlays |
| Bridge | window.BranchZero |
Godot never talks RPC; JS owns SDK reads + desk HTTP |
| Accounts | Bloxchain AccountBlox via @bloxchain/sdk |
Timelock, RBAC, guard whitelists — the bank’s rules |
| Identity | Privy embedded wallet + session signer + policy | One consent; tellers stamp slips without pop-ups |
| Names | ENSv2 subnames | Your bank name resolves to your account |
| FX | Uniswap v4 (practice USD / EUR / ILS) | Swap is three whitelisted calls on your account |
| Desk | Node 20 · Fastify · SSE | Provision, pay, wire, approve, cancel, status |
Hard rules: Godot never holds keys. Product runtime is public @bloxchain/sdk + viem (plus Privy). No custom Solidity in this repo. Testnets + lab chain only.
Architecture diagrams and sequences: docs/ARCHITECTURE.md.
MVP frozen (U4 / G5, 2026-09-07). Live Main payment wing on Sepolia; Remote EVM is Developer Mode. FX fiat desk live 2026-09-09. See docs/OWED.md for what’s open and parked.
Requirements: Windows, Node ≥ 20, Godot 4.5.2 standard (not mono).
npm install
cp .env.example .env # see docs for Privy + chain vars
npm run export:web # Godot → apps/web/public/game/
npm run dev:teller # Live desk :8787 (Sepolia)
npm run dev:web # http://localhost:5173| Mode | How |
|---|---|
| Mock walk (no chain) | http://localhost:5173/?mock=account |
| Live (Sepolia) | default — npm run dev:teller |
| Developer Mode (Remote EVM 1337) | npm run dev:teller:dev + ?mode=dev |
Full setup (Godot templates, Remote EVM, bootstrap, kill tests): docs/README.md · docs/GODOT.md · docs/SEPOLIA-LIVE.md.
npm -w apps/teller-desk run killtests -- --fresh # K2 / K5 / Lane Aapps/game/ Godot 4.5 project (GDScript). chain.gd is the only JavaScriptBridge user.
apps/web/ Vite shell + React overlay + window.BranchZero
apps/teller-desk/ Fastify — Privy auth key, broadcaster, lanes, SSE
packages/shared/ Chains, deployments schema, bridge types, ABI fragments
infra/ Deployments, pool scripts, funding helpers
docs/ Plan, design, architecture, sponsor notes
docs/media/readme/ Screenshots used above
| Start here | |
|---|---|
AGENTS.md |
Coding / ops agent entry (not the in-game robot) |
docs/PLAN.md |
Scope, gates, submission |
docs/GAME-DESIGN.md |
Player fantasy, loop, protocol ↔ desk map |
docs/ARCHITECTURE.md |
Layers, bridge, trust boundaries |
docs/game-knowledge/ |
iNPC-safe teaching pack (player-facing) |
docs/DEMO-SCRIPT.md |
3-minute video storyboard |
docs/PRIVY.md · ENS.md · UNISWAP.md |
Sponsor surfaces |
docs/REFLECTION.md |
Kill-test log and design review |
MIT. Bloxchain SDK is MPL-2.0. KayKit Adventurers and related kit assets retain their upstream licences — see attributions in apps/game/assets/.