勘定系（コアバンキング）リファレンスアーキテクチャ

import * as cdk from "aws-cdk-lib";
import { Construct } from "constructs";
import * as ec2 from "aws-cdk-lib/aws-ec2";
import * as ecs from "aws-cdk-lib/aws-ecs";
import * as elbv2 from "aws-cdk-lib/aws-elasticloadbalancingv2";
import * as rds from "aws-cdk-lib/aws-rds";

// 東京=Primary / 大阪=Warm Standby。外接系・営業店は Direct Connect + Transit Gateway で閉域接続。
export class CoreBankingStack extends cdk.Stack {
  constructor(scope: Construct, id: string, props?: cdk.StackProps) {
    super(scope, id, props);

    const vpc = new ec2.Vpc(this, "Vpc", { maxAzs: 2, natGateways: 1 });

    // 閉域接続：Transit Gateway（Direct Connect Gateway 経由でオンプレ/外接系と接続）
    const tgw = new ec2.CfnTransitGateway(this, "Tgw", { description: "core-banking-reference-tgw" });
    new ec2.CfnTransitGatewayAttachment(this, "TgwAttach", {
      transitGatewayId: tgw.ref,
      vpcId: vpc.vpcId,
      subnetIds: vpc.selectSubnets({ subnetType: ec2.SubnetType.PRIVATE_WITH_EGRESS }).subnetIds,
    });

    // 内部 ALB（インターネット非公開）配下に ECS Fargate の勘定系マイクロサービス
    const cluster = new ecs.Cluster(this, "Cluster", { vpc });
    const taskDef = new ecs.FargateTaskDefinition(this, "Task", { cpu: 1024, memoryLimitMiB: 2048 });
    taskDef.addContainer("app", { image: ecs.ContainerImage.fromRegistry("public.ecr.aws/nginx/nginx:stable"), portMappings: [{ containerPort: 80 }] });
    const svc = new ecs.FargateService(this, "Service", { cluster, taskDefinition: taskDef, desiredCount: 3 });
    const alb = new elbv2.ApplicationLoadBalancer(this, "InternalAlb", { vpc, internetFacing: false });
    alb.addListener("Http", { port: 80 }).addTargets("App", { port: 80, targets: [svc] });

    // Aurora Global Database（リージョン間レプリケーション。Warm Standby を大阪に保持）
    new rds.DatabaseCluster(this, "Aurora", {
      engine: rds.DatabaseClusterEngine.auroraPostgres({ version: rds.AuroraPostgresEngineVersion.VER_16_1 }),
      writer: rds.ClusterInstance.provisioned("writer"),
      vpc,
      storageEncrypted: true,
    });
    // NOTE: rds.CfnGlobalCluster と DynamoDB Global Table、Route 53 ARC / Step Functions による自動切替を追加します。
  }
}