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POSIX Time

Evolution SDK uses Unix timestamps in milliseconds (bigint) for all time-related operations. The UnixTime type represents milliseconds since the Unix epoch (January 1, 1970).

Getting Current Time​

const now = BigInt(Date.now())

const deadline = BigInt(new Date("2025-12-31T23:59:59Z").getTime())

Common Conversions​

const fiveMinutes = 5n * 60n * 1000n
const oneHour = 60n * 60n * 1000n
const oneDay = 24n * 60n * 60n * 1000n

const now = BigInt(Date.now())
const expiresIn5Min = now + fiveMinutes
const expiresIn1Hour = now + oneHour

Usage in Transactions​

Time values are passed to .setValidity() as Unix milliseconds. The builder converts them to slots automatically:

import { preprod, Client } from "@evolution-sdk/evolution"

const client = Client.make(preprod)
  .withBlockfrost({
    baseUrl: "https://cardano-preprod.blockfrost.io/api/v0",
    projectId: process.env.BLOCKFROST_API_KEY!
  })
  .withSeed({ mnemonic: process.env.WALLET_MNEMONIC!, accountIndex: 0 })

const now = BigInt(Date.now())

// Transaction valid for the next 10 minutes
// const tx = await client.newTx()
//   .setValidity({ from: now, to: now + 600_000n })
//   ...

Next Steps​

  • Slots — How Unix time maps to slots
  • Validity Ranges — Setting time constraints on transactions