Order processing (imported from Mermaid)

Order processing (imported from Mermaid) Order processing (imported from Mermaid) Imported from Mermaid; verify icon choices AWS Cloud HTTPS 1. Customer Browser → CloudFront CDN (HTTPS)1 2. CloudFront CDN → API Gateway2 3. API Gateway → Orders Lambda3 publish 5. Orders Lambda → Order Events SNS (publish)5 6. Order Events SNS → Fulfilment Queue6 7. Fulfilment Queue → Fulfilment Worker Function7 8. Fulfilment Worker Function → Receipts S3 Bucket8 status 10. Fulfilment Worker Function → Payment Gateway (status)10 write 4. Orders Lambda → Orders DynamoDB (write)4 9. Orders Lambda → CloudWatch Logs9 Customer Browser (Users) Customer Browser CloudFront CDN (Amazon CloudFront) CloudFront CDN API Gateway (Amazon API Gateway) API Gateway Orders Lambda (AWS Lambda) Orders Lambda Orders DynamoDB (Amazon DynamoDB) Orders DynamoDB Order Events SNS (Amazon Simple Notification Service) Order Events SNS CloudWatch Logs (Amazon CloudWatch) CloudWatch Logs Fulfilment Queue (Amazon Simple Queue Service) Fulfilment Queue Fulfilment Worker Function (AWS Lambda) Fulfilment Worker Function Receipts S3 Bucket (Amazon Simple Storage Service) Receipts S3 Bucket Payment Gateway (Generic Application) Payment Gateway

Flow

  1. 1Customer Browser → CloudFront CDN (HTTPS)
  2. 2CloudFront CDN → API Gateway
  3. 3API Gateway → Orders Lambda
  4. 4Orders Lambda → Orders DynamoDB (write)
  5. 5Orders Lambda → Order Events SNS (publish)
  6. 6Order Events SNS → Fulfilment Queue
  7. 7Fulfilment Queue → Fulfilment Worker Function
  8. 8Fulfilment Worker Function → Receipts S3 Bucket
  9. 9Orders Lambda → CloudWatch Logs
  10. 10Fulfilment Worker Function → Payment Gateway (status)

Cost estimate us-east-1 · price list as of 2026-10-02 · indicative — some usage is assumed

$25.18per month
$302per year
8/11components priced
1not priced (see below)

Public on-demand AWS list prices from the AWS Price List. Excludes free tier, taxes, support plans, Savings Plans/Reserved Instances/Spot and enterprise discounts, and data transfer unless a node sets egressGbPerMonth. Monthly = 730 hours. Not a quote: confirm with the AWS Pricing Calculator.

By category

Security and operations$12.30 · 49%
Integration$4.70 · 19%
Data and storage$4.45 · 18%
Compute$3.73 · 15%

By component click a row to highlight it on the diagram

ComponentServiceStatus$ / monthLine items
CloudWatch LogsAmazon CloudWatchestimated$12.30
4 lines
  • Log ingestion (GB): 10 GB × $0.50 = $5.00
  • Log storage (GB-month): 10 GB-Mo × $0.03 = $0.30
  • Custom metrics: 20 Metrics × $0.00 = $6.00
  • Standard-resolution alarms: 10 Alarms × $0.10 = $1.00
API GatewayAmazon API Gatewayestimated$3.50
1 line
  • REST API requests: 1,000,000 Requests × $0.00 = $3.50
Receipts S3 BucketAmazon Simple Storage Serviceestimated$3.20
3 lines
  • Storage, standard (GB-month): 100 GB-Mo × $0.00 = $2.30
  • PUT/COPY/POST/LIST requests: 100,000 Requests × $0.00 = $0.50
  • GET and other requests: 1,000,000 Requests × $0.00 = $0.40
Orders LambdaAWS Lambdaestimated$1.87
2 lines
  • Requests (x86): 1,000,000 Requests × $0.00 = $0.20
  • Compute duration (GB-seconds): 100,000 Lambda-GB-Second × $0.00 = $1.6667
Fulfilment Worker FunctionAWS Lambdaestimated$1.87
2 lines
  • Requests (x86): 1,000,000 Requests × $0.00 = $0.20
  • Compute duration (GB-seconds): 100,000 Lambda-GB-Second × $0.00 = $1.6667
Orders DynamoDBAmazon DynamoDBestimated$1.25
3 lines
  • On-demand read request units: 5,000,000 ReadRequestUnits × $0.00 = $0.625
  • On-demand write request units: 1,000,000 WriteRequestUnits × $0.00 = $0.625
  • Table storage (GB-month): 10 GB-Mo × $0.00 = $0.00

On-demand capacity mode; the Price List storage tier includes its first 25 GB at no charge.

Fulfilment QueueAmazon Simple Queue Serviceestimated$1.20
1 line
  • Standard queue requests: 3,000,000 Requests × $0.00 = $1.20

Not priced

  • CloudFront CDN — not-estimated: No cost model for Amazon CloudFront yet. Supply `usage.monthlyUsd` on the node to include it.
  • Order Events SNS — estimated: Excludes delivery charges for HTTP/SMTP/SMS endpoints; SQS and Lambda deliveries are free.

Assumptions 24 defaulted — replace them with your own numbers in each node's usage

ComponentAssumptionValueSource
API Gatewaytyperestassumed
API GatewayrequestsPerMonth1000000assumed
Orders LambdarequestsPerMonth1000000assumed
Orders LambdaavgDurationMs200assumed
Orders LambdamemoryMb512assumed
Orders Lambdaarchx86assumed
Orders DynamoDBreadRequestsPerMonth5000000assumed
Orders DynamoDBwriteRequestsPerMonth1000000assumed
Orders DynamoDBstorageGb10assumed
Order Events SNSpublishesPerMonth1000000assumed
CloudWatch LogslogIngestGbPerMonth10assumed
CloudWatch LogslogStorageGb10assumed
CloudWatch LogscustomMetrics20assumed
CloudWatch Logsalarms10assumed
Fulfilment Queuefifofalseassumed
Fulfilment QueuerequestsPerMonth3000000assumed
Fulfilment Worker FunctionrequestsPerMonth1000000assumed
Fulfilment Worker FunctionavgDurationMs200assumed
Fulfilment Worker FunctionmemoryMb512assumed
Fulfilment Worker Functionarchx86assumed
Receipts S3 BucketstorageClassstandardassumed
Receipts S3 BucketstorageGb100assumed
Receipts S3 BucketputRequestsPerMonth100000assumed
Receipts S3 BucketgetRequestsPerMonth1000000assumed

Sensitivity & what-if

$25.18at 1× traffic
$63.80at 3× traffic
$212at 10× traffic
  • Run Orders Lambda on arm64 (Graviton) — saves $0.33/month. Same usage re-priced with arm64 request and duration rates; assumes the code runs unchanged on arm64.
  • Run Fulfilment Worker Function on arm64 (Graviton) — saves $0.33/month. Same usage re-priced with arm64 request and duration rates; assumes the code runs unchanged on arm64.

Price list provenance

Retrieved 2026-10-01T18:40:39.861Z from the public AWS Price List bulk API. Per-service publication dates:

AmazonApiGateway 2026-09-21 · AWSLambda 2026-09-19 · AmazonDynamoDB 2026-09-11 · AmazonSNS 2026-09-15 · AmazonCloudWatch 2026-09-22 · AWSQueueService 2026-09-11 · AmazonS3 2026-09-28

Only public on-demand rates are used. This is not a quote — confirm in the AWS Pricing Calculator.