@main
struct Main {
    static func main() async throws {
        let client = try await S3Client()
        // ... async operations
    }
}

// CORRECT - struct config
let config = try await S3Client.S3ClientConfig(region: "us-west-2")
let client = S3Client(config: config)

// WRONG - deprecated class
// let config = try await S3Client.S3ClientConfiguration(region: "us-west-2")

import AWSS3
import AWSDynamoDB

// Simple - auto-detects region
let s3 = try await S3Client()
let dynamo = try await DynamoDBClient()

// With region
let s3 = try S3Client(region: "us-west-2")

// With config - parameters must be in declaration order
let config = try await S3Client.S3ClientConfig(
    useFIPS: true,
    awsRetryMode: .adaptive,
    maxAttempts: 5,
    region: "us-west-2"
)
let client = S3Client(config: config)

// With custom endpoint and credentials
let config = try await S3Client.S3ClientConfig(
    awsCredentialIdentityResolver: resolver,
    region: "us-west-2",
    endpoint: "https://s3.custom-endpoint.com"
)

import AWSSDKIdentity
import SmithyIdentity

// Static credentials - pass credential object directly
let creds = AWSCredentialIdentity(accessKey: "AKIA...", secret: "...")
let resolver = StaticAWSCredentialIdentityResolver(creds)

// Assume role - REQUIRES underlying resolver
let underlying = try DefaultAWSCredentialIdentityResolverChain()
let resolver = try STSAssumeRoleAWSCredentialIdentityResolver(
    awsCredentialIdentityResolver: underlying,
    roleArn: "arn:aws:iam::123456789012:role/MyRole",
    sessionName: "session-name"
)

// Use in config
let config = try await S3Client.S3ClientConfig(
    awsCredentialIdentityResolver: resolver,
    region: "us-west-2"
)

import AWSS3
import SmithyWaitersAPI

let client = try await S3Client()
_ = try await client.waitUntilBucketExists(
    options: WaiterOptions(maxWaitTime: 120.0),
    input: HeadBucketInput(bucket: "my-bucket")
)

let input = ListObjectsV2Input(bucket: "my-bucket")
for try await page in client.listObjectsV2Paginated(input: input) {
    for object in page.contents ?? [] {
        print(object.key ?? "")
    }
}

let url = try await client.presignedURLForGetObject(
    input: GetObjectInput(bucket: "my-bucket", key: "file.pdf"),
    expiration: 3600
)

// Put object
_ = try await client.putObject(input: PutObjectInput(
    body: .data(data),
    bucket: "bucket",
    key: "key"
))

// Get object
let output = try await client.getObject(input: GetObjectInput(bucket: "bucket", key: "key"))
let data = try await output.body?.readData()

// List buckets
let response = try await client.listBuckets(input: ListBucketsInput())
for bucket in response.buckets ?? [] {
    print(bucket.name ?? "")
}