aiken new my-project
cd my-project

my-project/
├── aiken.toml           # Project config
├── lib/                 # Reusable modules
├── validators/          # Validator entry points
│   └── my_validator.ak
└── plutus.json          # Generated blueprint

// validators/my_validator.ak
use aiken/transaction.{ScriptContext}

validator {
  fn spend(datum: Data, redeemer: Data, ctx: ScriptContext) -> Bool {
    // Your validation logic
    True
  }
}

# Build all validators
aiken build

# Run tests
aiken check

# Format code
aiken fmt

# Blueprint is auto-generated at plutus.json
# Extract .plutus for cardano-cli:
aiken blueprint convert > my_validator.plutus

# Get script hash
cardano-cli conway transaction policyid \
  --script-file my_validator.plutus

cardano-cli conway address build \
  --payment-script-file my_validator.plutus \
  --testnet-magic 1 \
  --out-file script.addr

// validators/pubkey_lock.ak
use aiken/hash.{Blake2b_224, Hash}
use aiken/transaction.{ScriptContext, Spend}
use aiken/transaction/credential.{VerificationKey}

type Datum {
  owner: Hash<Blake2b_224, VerificationKey>
}

type Redeemer {
  // Could be unit if no redeemer data needed
}

validator {
  fn spend(datum: Datum, _redeemer: Redeemer, ctx: ScriptContext) -> Bool {
    let ScriptContext { transaction, purpose } = ctx
    expect Spend(_) = purpose

    // Check if owner signed the transaction
    list.has(transaction.extra_signatories, datum.owner)
  }
}

# Build
aiken build

# Test
aiken check

# Generate .plutus
aiken blueprint convert > pubkey_lock.plutus

// validators/time_lock.ak
use aiken/interval.{Finite, Interval, IntervalBound}
use aiken/transaction.{ScriptContext, ValidityRange}

type Datum {
  lock_until: Int  // POSIX time in milliseconds
}

validator {
  fn spend(datum: Datum, _redeemer: Data, ctx: ScriptContext) -> Bool {
    let valid_range: ValidityRange = ctx.transaction.validity_range

    // Check if current time is past lock_until
    when valid_range.lower_bound.bound_type is {
      Finite(tx_earliest_time) -> tx_earliest_time > datum.lock_until
      _ -> False
    }
  }
}