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CRUMB

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What the simulation does and does not do

Your deposit is real and withdrawable anytime. Yield and stock crumbs are simulated. The exact boundary, and how the numbers are computed.

What the simulation does

  • Connects to your real wallet on Robinhood Chain (chain ID 4663).
  • Lets you deposit real USDG into the real CrumbVault contract, after approving the exact amount only.
  • Lets you withdraw part or all of your deposit at any time, with no fee, lock or delay.
  • Reads your deposit history from the contract and computes, in your browser, what that deposit would have earned at an illustrative 7% APY.
  • Splits that simulated yield into weekly crumb drops, every Monday at 9:30 AM Eastern Time, tagged with the stock you selected.

What the simulation does not do

  • It does not pay interest. The vault holds your USDG idle. Nothing is lent out, so nothing is earned.
  • It does not buy stock tokens. No swap is ever executed. Crumbs are figures on a screen.
  • It does not owe you the simulated amounts. They are not a balance, a claim, points, or an airdrop allocation.
  • It does not quote share counts. Crumbs are shown as approximate USD value, labelled "simulated", because the app does not read a stock price feed.
  • It does not store anything about you on a server. There is no backend. Your stock choice lives in your browser's local storage.

Why launch a simulation at all

Because the honest way to earn trust is in small steps. The simulation proves the part that matters most before anything else exists: a vault you can enter and leave freely, with code simple enough to read in ten minutes. It also lets you experience the weekly rhythm of the product with nothing at stake beyond a few cents of gas.

How the numbers are computed

Every time you deposit or withdraw, CrumbVault records a checkpoint: a timestamp and your new balance. The app reads this list with a single call and computes:

crumbs(t0, t1) = Σ  balance_i × seconds_i × (7% / seconds_per_year)

That is simple interest, time-weighted over your actual on-chain balance. If you withdraw half, accrual halves from that second. If you withdraw everything, it stops. The total is then cut into windows ending at each Monday 9:30 AM ET; each closed window is one row of your drop history, and the open window is the live counter at the top of the app.

Because the inputs are on-chain, the result is the same on any device and survives clearing your browser. Because the output is simulated, none of it is withdrawable.

Preview mode

When no wallet is connected, or the connected wallet has never deposited, the panel shows a clearly labelled preview: a hypothetical deposit made 28 days ago, with an amount you can edit. It exists so you can see the product before touching it. Nothing in preview mode is on-chain.