Skip to content
Lambda Web Functions Walkthrough

Prerequisites

Time and cost

Section titled “Time and cost”
~30–45 minConsole path
PenniesIf torn down promptly — requests + active CPU + memory while an env exists

Region

Section titled “Region”

Web Functions is not available in every Region. Set a supported Region first.

Initial Regions:

  • us-east-1 — N. Virginia
  • us-east-2 — Ohio
  • us-west-2 — Oregon
  • ap-northeast-1 — Tokyo
  • eu-west-1 — Ireland

Current list: AWS Capabilities by Region.

AWS Lambda console Region set to United States (N. Virginia) with Web Functions (New) in the left nav

Lab names

Section titled “Lab names”
wf-helloWeb Function
devEndpoint

What create produces

Section titled “What create produces”

Always created (console or CLI):

wf-hello + revision + endpoint devauth: Application-managed (public)
always

Only if you run aws lambda-web deploy (extras to clean up later):

IAM role awscli-lambdaweb-wf-helloonly on aws lambda-web deploy
S3 prefix lambda-web/wf-hello/only on aws lambda-web deploy
Log group /aws/lambda/web/wf-helloafter first request (+ .local companion)

IAM

Section titled “IAM”

Console: manage Web Functions / revisions / endpoints · iam:PassRole · use console role + code bucket.

CLI deploy (additive): sts:GetCallerIdentity · S3 list/put/get/version · if defaults: IAM create role + put policy · S3 create bucket + policy + versioning. Pass the CLI gate first.

CLI gate (optional path)

Section titled “CLI gate (optional path)”

Skip this section if you stay on the AWS Management Console and curl only.

Terminal window
aws --version
aws-cli/2.37.4 Python/3.14.6 Linux/7.0.0-30-generic exe/x86_64.ubuntu.24

Your build string will differ. Note the version — you need a CLI that ships lambda-web (reference docs show 2.38.0+).

Terminal window
aws lambda-web help

Pass — help lists Web Function commands:

NAME
       lambda-web -


AVAILABLE COMMANDS
       o create-web-function
       o create-web-function-endpoint
       o create-web-function-revision
       o delete-resource-policy
       o delete-web-function
       o delete-web-function-endpoint
       o delete-web-function-revision
       o deploy
       o get-resource-policy
       o get-web-account-settings
       o get-web-function
       o get-web-function-endpoint
       o get-web-function-revision
       o list-tags
       o list-web-function-endpoints
       o list-web-function-revisions
       o list-web-functions
       o put-resource-policy
       o tag-resource
       o untag-resource
       o update-web-function-endpoint
       o wait

Gate passed → use the optional CLI later on Optional Express and CLI.

Fail — older CLI (authoring host evidence on 2.37.4):

aws: [ERROR]: An error occurred (ParamValidation): argument command: Found invalid choice 'lambda-web'




usage: aws [options] <command> <subcommand> [<subcommand> ...] [parameters]
To see help text, you can run:


  aws help
  aws <command> help
  aws <command> <subcommand> help

Then update:

Terminal window
aws update

Output varies by how the AWS CLI was installed. When it finishes, retry:

Terminal window
aws lambda-web help

Expect the same Pass listing above.

Still failing after update → CLI install/update · Troubleshooting.