While AWS Lambda is a powerful serverless compute service, it isn't suitable for every use case. Certain limitations and architectural constraints make it less ideal in some scenarios.
Long-running processes: Lambda has a maximum timeout of 15 minutes per invocation.
Applications needing persistent connections: WebSockets, long polling, or streaming over extended periods is not ideal.
Heavy resource requirements: Compute- or memory-intensive workloads may exceed Lambda's limits.
Low-latency or real-time systems: Cold start delays in Lambda can be problematic for latency-sensitive applications.
Stateful applications: Lambda is inherently stateless and unsuitable for apps needing persistent in-memory state.
Amazon EC2 – for full control over environment and persistent applications.
Amazon ECS or EKS – for container-based workloads requiring orchestration.
AWS Step Functions – for orchestrating multiple Lambda functions or managing complex workflows.
Understanding when not to use Lambda helps ensure better architectural choices, cost efficiency, and performance for your applications. Choose the right compute model based on the application's specific needs and workload characteristics.
0-2 years experience
Complex container or OS-level configurations: If your app needs custom networking, file system access, or non-standard libraries, EC2 or ECS is better.
2-5 years experience
5-8 years experience
8+ years experience
