It all started with a simple question:
“What’s the actual difference between AWS Lambda and Azure Functions? I want to figure out what to benckmark”
We all froze for a second. One of us mumbled something about tiers in Azure and how Premium Functions can run longer. But the real save came from our architect Prakash, who, as always, saw through the chaos:
“Guys… Lambda is AWS. Azure Function is native to Azure.”
We all nodded solemnly:
“Thank you, Prakash. Truly enlightening!“
But let’s not leave it at that. Here’s the actual breakdown, for those of us who plan to remember it next time.
🪄 The TL;DR Table
| Feature | AWS Lambda | Azure Functions |
| 🏰 Native Platform | AWS | Azure |
| ⏱️ Max Execution Time | 15 minutes | 5–10 min (Consumption) / 60 min (Premium) |
| ❄️ Cold Start Handling | Provisioned Concurrency | Premium Plan keeps it warm |
| 📦 Packaging & Deployment | ZIP, container, SAM, CDK | Zip, Git, Kudu, GitHub, Azure DevOps, FTP |
| 🔀 Orchestration Options | Step Functions | Durable Functions |
| 🧠 Supported Languages | JS, Python, Java, C#, Go, Ruby | JS, Python, C#, Java, PowerShell, F# |
| 💰 Pricing Model | Pay-per-use (invocation+GB-sec) | Same model, minor differences in details |
| 📊 Monitoring Tools | CloudWatch, X-Ray | App Insights, Log Analytics |
The Real Answer
If you’re asking “which one should I benchmark?”, you’re probably building in both clouds. And that’s okay.
Here’s your checklist:
- Test cold start time
- Check scaling behavior under load
- Monitor latency under stress
- Validate integration latency (e.g., database, storage, queues)
Both platforms are battle-tested. But they shine in their own kingdoms.
🧱 Well-Architected Framework Comparison: Lambda vs Azure Functions
| Pillar | AWS Lambda | Azure Functions |
| 💸 Cost Optimization | ✅ 1M free invocations/month. | ✅ Also 1M free/month. |
| ✅ Pay-per-use (ms + memory). | ✅ Multiple tiers (Consumption, Premium). | |
| ⚠️ Provisioned Concurrency costs extra. | ✅ Premium = predictable pricing for enterprise use. | |
| ⚙️ Operational Excellence | ✅ CloudWatch logs + X-Ray tracing. | ✅ App Insights + Log Analytics. |
| ✅ CI/CD via SAM/CDK. | ✅ Azure DevOps/GitHub Actions native. | |
| ⚠️ Requires setup for canary deployments. | ✅ Deployment slots for staged rollouts. | |
| 🔁 Reliability | ✅ Auto-scaling built-in. | ✅ Auto-scaling built-in (Consumption & Premium Plans) |
| ⚠️ Regional only (multi-region via Route 53 + Global Accelerator). | ⚠️ Also regional — supports Availability Zones for intra-region resilience. Multi-region via Traffic Manager / Front Door. | |
| ⚠️ Event sources like SQS need manual DLQ config. | ✅ Built-in retries for many triggers. | |
| 🏎️ Performance Efficiency | ✅ Fast for small, short-lived workloads. | ✅ Premium Plan = always warm, up to 60 mins. |
| ✅ Provisioned Concurrency for consistent perf. ⚠️ Cold starts without it. | ⚠️ Isolated worker slower on cold start. ✅ Good for .NET-heavy tasks. | |
| 🔐 Security | ✅ IAM for access control. | ✅ Azure AD + RBAC. |
| ✅ VPC integration (with some extra config). | ✅ VNET integration (easy in Premium). | |
| ✅ Secrets via Secrets Manager. | ✅ Azure Key Vault. | |
| ⚠️ No native Private Endpoint — workaround via internal ALB or private API Gateway | ✅ Native Private Endpoint support (Premium Plan) |
👑 Verdict: Who Freezes Harder?
| Scenario | Winner |
| You need cheapest possible setup | Tie (but suffer cold starts) |
| You need fast startup | Azure (Premium) 🥇 |
| You want fine-tuned warm control | Lambda (Provisioned) 🥇 |
| You hate JIT | Lambda + AOT (if stable) |
| You use isolated worker model | Azure — but be careful ⚠️ |
❄️ In serverless, everyone freezes. But some freeze smarter.
Cold starts will always be part of the serverless game. Azure gives you comfort with Premium Plans and better .NET support, while AWS offers precision control through Provisioned Concurrency and bleeding-edge AOT options.
Choose your weapon based on project needs, budget, and how much frostbite you’re willing to tolerate.
🎁 Bonus: When to Use Which?
| If You Need… | Go With… |
| Full Azure integration (e.g. VNETs, AAD) | Azure Functions |
| Super fast spin-up & simplicity | AWS Lambda |
| Multi-step Orchestration with retries/timeouts | Durable Functions (Azure) or Step Functions (AWS) |
| Always-warm, long-running execution | Azure Premium Plan |
| Easy container packaging | AWS Lambda |
| Exotic runtime like F# | Azure |
| Quick prototyping, low cost | AWS Lambda (Consumption) |
| Max control over IAM policies | AWS Lambda |
| Want easy VNET + identity integration | Azure Functions |
Summary
As Mr. Prakash said: “Lambda is AWS. Azure Function is Azure.”
Sometimes, the simplest truths come from the wisest mouths.