AWS Lambda vs Amazon RDS

Serverless computing that makes you feel like a wizard—until you get hit with cold starts and vendor lock-in meets managed databases for people who'd rather not manage databases. Here's our take.

AWS Lambda

Nice Pick

Serverless computing that makes you feel like a wizard—until you get hit with cold starts and vendor lock-in.

Pros

• No server management—just upload code and it runs automatically
• Auto-scales from zero to thousands of concurrent executions
• Pay-per-use pricing model (you only pay for compute time)
• Integrates seamlessly with other AWS services like S3 and API Gateway

Cons

• Cold starts can cause unpredictable latency spikes
• Vendor lock-in with AWS ecosystem makes migration painful
• Limited execution time and memory constraints (up to 15 minutes)

Amazon RDS

Managed databases for people who'd rather not manage databases. It's like having a DBA on retainer, but cheaper and less opinionated.

Pros

• Automates backups, patching, and scaling, so you can focus on your app instead of babysitting servers
• Supports multiple engines like PostgreSQL and MySQL, making it easy to switch or standardize
• Built-in high availability with Multi-AZ deployments, because downtime is for amateurs

Cons

• Costs can sneak up on you with instance sizes and storage, especially if you forget to turn things off
• Limited control over the underlying OS and some database settings, which can be frustrating for power users

The Verdict

Use AWS Lambda if: You want no server management—just upload code and it runs automatically and can live with cold starts can cause unpredictable latency spikes.

Use Amazon RDS if: You prioritize automates backups, patching, and scaling, so you can focus on your app instead of babysitting servers over what AWS Lambda offers.

The Bottom Line

AWS Lambda wins

Serverless computing that makes you feel like a wizard—until you get hit with cold starts and vendor lock-in.