Transaction simulation

In one sentence: run a Solana transaction as a dry run, compare account snapshots before vs after, and return human-readable balance rows for the approval screen.

Used by the auth app so users see estimated changes before they sign—similar to Phantom wallet.

Using it in code

import { simulateInstructions } from "@revibase/transaction-simulation";

const result = await simulateInstructions({
  rpcEndpoint: "https://api.mainnet-beta.solana.com",
  walletAddress,
  payer: walletAddress,
  instructions,
  addressesByLookupTableAddress, // optional
});

// result.balanceChanges  — amounts going up/down
// result.status            — "succeeded" | "failed"

Folder map (where things live)

src/
  simulate-instructions.ts   ← main entry you call
  simulate.ts                ← RPC compile + simulateTransaction
  types/                     ← shared types (parsers, simulation API)
  parsers/
    run.ts                   ← account snapshot diff orchestration
    parsed-row.ts            ← finalize rows + pending mint merge
    account-guard.ts         ← guardAccountDiff for account parsers
    plugin-kit/              ← shared fungible helpers
    plugins/                 ← one folder per on-chain program
  utils/labels/              ← user-visible text (“Your Wallet”, …)

Scripts

| Command | What it does | |---------|----------------| | pnpm test | Run all tests | | pnpm build | Build package for publish / app |