Compute
Where business logic runs.
My default
One tool in this layer.
My default for event-driven work and heavy compute. Classic Lambda, zip-packaged, Node.js.
Pricing: $0.20 per million requests + $0.0000133334/GB-s on Arm ($0.0000166667 on x86). Free tier: 1M requests and 400,000 GB-s a month, always.
Use when it fits
One tool in this layer.
Containers that run only while the job runs. The answer for a two-hour nightly job.
Pricing: Per second of vCPU and memory while the task runs (one-minute minimum). Nothing between runs. Fargate Spot is cheaper if the job can be interrupted. Sydney, ARM: $0.03885 per vCPU-hour and $0.00426 per GB-hour; x86: $0.04856 and $0.00532. A two-hour nightly run on 2 vCPU and 4 GB (ARM) is about $5.70 a month, against about $69 for the same task left running all month. 20 GB of disk is included.
Watching
One tool in this layer.
A real Node.js web server on Lambda, billed on CPU used, 64 to 128 requests per environment. The future of HTTP business logic on AWS. Not in Sydney yet.
Pricing: $0.30 per million requests + $0.0000279955 per active vCPU-second + $0.0000037065 per GB-second of memory consumed while the environment lives (Sydney price-list rates; not launched there yet). Free tier: not stated.
Never
One tool in this layer.
Worse cold starts, and they break Cognito triggers. I stopped using them.
Pricing: No extra Lambda charge: the same requests and compute as a zip function. The image lives in ECR at $0.10 per GB-month in Sydney.
Instead: Zip-packaged Lambda functions, or Fargate when you really need a container.
Where they're used
The jobs that pick or avoid a tool from this layer.
- 01 An API for my app I need a backend API that reads and writes a database. My picks: Lambda function URLs, Neon (serverless Postgres), Lambda Web Functions, Cloudflare Workers
- 02 An AI chat or LLM feature My app needs to call an LLM and stream the answer to users. My picks: Cloudflare Workers, OpenRouter, pgvector, Cloudflare AI Gateway
- 04 A traffic spike I can see coming A flash sale, ticket drop or launch where thousands hit at once. My picks: Cloudflare Workers, Cloudflare Durable Objects, AWS Lambda, Stripe
- 06 Background jobs and retries Work that runs after the request, with retries. My picks: Amazon SQS, AWS Lambda, Amazon EventBridge, Lambda durable functions
- 08 A job that runs for hours A nightly import, report or migration longer than 15 minutes. My picks: Fargate scheduled tasks, Amazon EventBridge
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Cloudless Labs is a Sydney consultancy. We migrate on-premises systems to AWS, build serverless apps on this stack, and coach teams to ship with Claude Code and Codex.