Free AWS Security Whitepaper
    Toc Consulting Logo
    compareecs-vs-eks-vs-lambda-vs-apprunner
    COMPUTEPublished 2025-11-01Updated 2025-12-15
    Amazon ECSAmazon ECS
    vs
    Amazon EKSAmazon EKS
    vs
    AWS LambdaAWS Lambda
    vs
    AWS App RunnerAWS App Runner

    ECS vs EKS vs Lambda vs App Runner

    AWS compute - from zero management to full control

    Four ways to run code on AWS, from fully serverless (Lambda) to fully managed Kubernetes (EKS). The right choice depends on your team size, operational maturity, workload patterns, and security requirements. We include the security implications most comparison articles ignore.

    Service Overview

    Amazon ECS

    Amazon ECS

    AWS-native containers

    Simple container orchestration with deep AWS integration

    TypeContainer orchestration
    PricingFree (ECS) + Fargate ($0.04048/vCPU/hr) or EC2
    Amazon EKS

    Amazon EKS

    Managed Kubernetes

    Full Kubernetes API - portable, ecosystem, community

    TypeKubernetes orchestration
    Pricing$0.10/cluster/hr (~$73/mo) + Fargate or EC2 nodes
    AWS Lambda

    AWS Lambda

    Serverless functions

    Zero infrastructure, sub-second scaling, pay per invocation

    TypeEvent-driven compute
    Pricing$0.20/1M requests + $0.0000166667/GB-sec
    AWS App Runner

    AWS App Runner

    Fully managed containers

    Simplest option - push code or image, get a URL

    TypeSource-to-URL deployment
    Pricing$0.064/vCPU/hr (active) + $0.007/GB/hr (memory)

    Side-by-Side Comparison

    $ diff --side-by-side
    CriteriaECSEKSLambdaApp Runner
    Operational ComplexityMediumHighLowVery Low
    Max Execution TimeUnlimitedUnlimited15 minutesUnlimited
    Cold Start~5-30s (Fargate)~5-30s (Fargate)~100ms-10s (varies by runtime)~5-15s
    Auto-ScalingECS Service Auto ScalingKarpenter / HPA / VPAInstant (concurrent invocations)Automatic (built-in)
    VPC SupportYesYesOptional (minimal cold start impact since Hyperplane ENI)Yes (limited)
    GPU SupportYes (EC2)Yes (EC2)NoNo
    Cloud PortabilityNo (AWS-native)Yes (Kubernetes)No (AWS-native)No (AWS-native)
    Team Size Needed2-5 engineers5+ engineers (Kubernetes expertise)1-2 engineers1 engineer

    When to Use What

    $ cat DECISION_GUIDE.md
    IFYou are a small team building web APIs and microservices
    THENECS on Fargate
    WHYBest balance of simplicity and control. No servers to manage, deep AWS integration, and simpler than Kubernetes.
    IFYour team already uses Kubernetes and needs cloud portability
    THENEKS
    WHYFull Kubernetes API compatibility. Migrating from on-prem or another cloud? EKS preserves your Helm charts, operators, and YAML.
    IFYou have event-driven, bursty workloads under 15 minutes
    THENLambda
    WHYPay nothing when idle. Scales to thousands of concurrent executions instantly. No containers to build.
    IFYou want the absolute simplest deployment with minimal config
    THENApp Runner
    WHYPoint it at a GitHub repo or ECR image. It builds, deploys, scales, and gives you an HTTPS URL. No VPC, no security groups, no task definitions.
    IFYou need GPU workloads for ML inference
    THENECS or EKS on EC2
    WHYLambda and App Runner do not support GPUs. Use EC2 launch type with p5 or inf instances.

    Security Insights

    Lambda has the smallest attack surface

    No SSH, no OS patches, no container images to scan. AWS manages the runtime. The attack surface is limited to your function code, dependencies, and IAM execution role.

    EKS requires Kubernetes security expertise

    RBAC misconfigurations, pod security standards, service account token abuse, and OIDC federation attacks are all EKS-specific risks. Do not run EKS without dedicated Kubernetes security knowledge.

    IMDSv1 is still the default on EC2-backed ECS/EKS

    If you use EC2 launch type, enforce IMDSv2 to prevent SSRF-based credential theft from the instance metadata service. This is the most exploited attack vector in AWS.

    Task/Pod IAM roles are essential

    Never use EC2 instance roles for containers. Use ECS task roles or EKS IRSA (IAM Roles for Service Accounts) to scope permissions per workload, not per instance.

    Key Takeaways

    $ cat SUMMARY.md
    1.ECS Fargate = sweet spot for most teams (simple, serverless containers, deep AWS integration)
    2.EKS = only if you need Kubernetes compatibility or cloud portability
    3.Lambda = event-driven, bursty, <15 min. Smallest attack surface.
    4.App Runner = simplest deployment, minimal config, but limited customization
    5.Security: enforce IMDSv2 on EC2, use task/pod IAM roles, scan container images with ECR + Inspector
    ContainersServerlessKubernetesCompute

    Need Architecture Guidance?

    These comparisons are a starting point. Every architecture is different. Contact us for tailored AWS security assessments and architectural guidance.

    All ComparisonsGet in Touch