3-5 years in software engineering.Experience in AWS.Experience in C#/.NET.Experience in Node.js/TypeScript.Experience in HTTP, REST, JSON, async programming.Experience in SQL Server.Experience in NoSQL (DynamoDB preferred).Experience in Git, trunk/pr workflows, and CI/CD pipelines.Experience in unit/integration testing, mocking, and test data strategies.Experience in cloud logs/metrics/traces.Experience in CloudWatch/X-Ray.Experience in OpenAPI/Swagger.Experience in AWS Step Functions.Experience in SNS/SQS.Experience in Kinesis or Kafka.Experience in AWS CDK (TypeScript/C#) or Terraform.Experience in OpenTelemetry, structured logging, and distributed tracing.Experience in Cognito, custom JWT authorizers, WAF, Secrets Manager, parameterized/IAC-managed IAM.Experience in API design: pagination, filtering, versioning, OpenAPI first.Experience in gRPC.Experience in frontend integration (CORS, rate limiting, API keys, 429 strategies).Experience in Docker.Experience in ECS/Fargate or EKS.Experience in performance tuning (.NET profilers, async best practices, DynamoDB access patterns).Experience in high-throughput transactional systems or B2B integrations.