Glossary

A

Arbitrum Stylus A next-generation upgrade to the Arbitrum Nitro stack that allows developers to write smart contracts in languages that compile to WASM, such as Rust, C++, and C, alongside traditional Solidity contracts.

B

Beneficiary The wallet address designated by the Vault Owner to receive the assets in the event of the Owner's incapacitation.

C

Claim The function called by the Beneficiary to transfer assets from the Vault to their own wallet. This function only succeeds if the Heartbeat Timer has expired.

Compound Interest Interest calculated on the initial principal, which also includes all of the accumulated interest from previous periods. LegacyVault calculates this daily (1%).

D

Dead Man's Switch A switch that is designed to be activated or deactivated if the human operator becomes incapacitated, such as through death, loss of consciousness, or being bodily removed from control.

Duration (Heartbeat) The maximum allowed time interval between "Pings". If this time elapses without a Ping, the Vault status changes to CLAIMABLE.

F

Factory Pattern A design pattern where one "Factory" contract is used to deploy and manage multiple instances of another "Child" contract (Vaults). LegacyVault uses this to make creating new vaults cheap for users.

H

Heartbeat See Duration.

I

Iterative Calculation A mathematical method used in our Rust contract where interest is calculated by looping through every single day (for day in days). This ensures maximum precision compared to estimation formulas.

L

Lending Pool The internal Rust-based smart contract (0x...) where user funds are stored to generate yield. It acts as the "Bank" of the LegacyVault ecosystem.

M

MockUSDC A testnet ERC-20 token with 6 decimals used to simulate real USDC stablecoins for the purpose of the Hackathon demonstration.

O

Owner The creator of the Vault. The Owner has exclusive rights to Deposit, Withdraw, and Ping the vault while the status is Active.

P

Ping A transaction sent by the Owner to the Vault Logic contract. Its sole purpose is to update the last_ping timestamp to the current time, effectively resetting the Dead Man's Switch timer.

Proxy (Minimal Proxy) A cheap clone of a master smart contract (EIP-1167). Each user gets their own Proxy Address, but they all share the same underlying Logic code.

R

Rust A systems programming language known for its performance and memory safety. LegacyVault uses Rust (via Stylus) for all complex logic and math.

S

Stylus SDK The software development kit provided by Offchain Labs that allows Rust programs to interact with the Arbitrum blockchain (reading storage, sending tokens, etc.).

W

WASM (WebAssembly) A binary instruction format for a stack-based virtual machine. Arbitrum Stylus executes WASM binaries, which is faster and cheaper than the traditional EVM.