Kotlin SDK Quickstart

This quickstart gets you from dependency setup to a confirmed transaction using the current Kaptos API shape.

1. Install the SDK

   Kaptos publishes multiplatform and platform-specific artifacts to Maven Central.

   Multiplatform

   kotlin {
     sourceSets {
       commonMain.dependencies {
         implementation("xyz.mcxross.kaptos:kaptos:<version>")
       }
     }
   }

   JVM (example)

   dependencies {
     implementation("xyz.mcxross.kaptos:kaptos-jvm:<version>")
   }

2. Configure the client

   val aptos = Aptos(
     AptosConfig(
       settings = AptosSettings(
         network = Network.DEVNET,
         clientConfig = ClientConfig(maxRetries = 10),
       )
     )
   )

   注意

   Kaptos is Kotlin Multiplatform. Some HTTP client options differ slightly by target, but API usage stays consistent.

3. Read chain data

   val ledgerInfo = aptos.getLedgerInfo().expect("Failed to fetch ledger info")
   println("Ledger version: ${ledgerInfo.ledgerVersion}")
   
   val chainId = aptos.getChainId().expect("Failed to fetch chain id")
   println("Chain id: $chainId")

4. Create and fund accounts

   val alice = Account.generate()
   val bob = Account.generate()
   
   aptos.fundAccount(accountAddress = alice.accountAddress, amount = 100_000_000L).expect("Failed to fund Alice")
   aptos.fundAccount(accountAddress = bob.accountAddress, amount = 100_000_000L).expect("Failed to fund Bob")

   For single-key and multi-key account patterns, see Accounts.

5. Build and send a transaction

   The lean transaction builder uses typeArgs(...) and args(...).

   val pendingTxn =
     aptos
       .execute(signer = alice) {
         function = "0x1::coin::transfer"
         typeArgs("0x1::aptos_coin::AptosCoin")
         args(bob.accountAddress, 1_000_000UL)
       }
       .expect("Failed to build/sign/submit transaction")

6. Wait for confirmation

   val executedTxn =
     aptos
       .waitForTransaction(HexInput.fromString(pendingTxn.hash))
       .expect("Transaction did not execute successfully")
   
   println("Executed transaction version: ${executedTxn.version}")

Need finer control (separate build/sign/submit, fee-payer flow, simulation)? See Building Transactions.