Standup Bot

Slack bot that automates async standups for distributed teams. Every morning it DMs each team member three questions, collects responses, then uses an LLM (Claude or Ollama/Qwen) to summarise everything into a daily digest posted to a designated channel.

How it works

1. Morning - EventBridge triggers the prompt handler, which DMs each team member via Slack
2. Team replies - Members reply in the DM thread with a numbered list (what they did, what they're doing, blockers)
3. Digest time - EventBridge triggers the digest handler, which collects responses, generates an AI summary, and posts a formatted digest to the team's Slack channel

Architecture

EventBridge (cron)  -->  Lambda: prompt handler  -->  Slack DMs
Slack events        -->  API Gateway  -->  Lambda: event handler  -->  DynamoDB
EventBridge (cron)  -->  Lambda: digest handler  -->  Claude/Ollama  -->  Slack channel

Three Lambda handlers share a single DynamoDB table using a single-table design:

PK	SK	Data
TEAM#{teamId}	CONFIG	Team configuration
TEAM#{teamId}	RESPONSE#{date}#{userId}	Standup response
TEAM#{teamId}	DIGEST#{date}	Generated digest
THREAD#{threadTs}	MAPPING	Thread-to-user mapping

A GSI on SK enables efficient team config lookups without full table scans.

Tech stack

• Runtime: Node.js 24.x on AWS Lambda
• Language: TypeScript 5.x
• Slack: @slack/bolt + @slack/web-api
• AI: Claude Haiku (production) or Ollama/Qwen (local dev)
• Database: DynamoDB (single table, PAY_PER_REQUEST, GSI on SK)
• Infra: AWS CDK, EventBridge, API Gateway (with throttling)
• Secrets: SSM Parameter Store (SecureString)
• Validation: Zod
• Testing: Vitest
• Bundling: esbuild

Project structure

src/
  handlers/
    prompt.ts           # Cron: send standup DMs to team members
    event.ts            # HTTP: receive and store Slack responses
    digest.ts           # Cron: generate and post daily summary
  services/
    slack.ts            # Slack API wrapper
    claude.ts           # Claude summarisation service
    ollama.ts           # Ollama/Qwen summarisation service
    dynamo.ts           # DynamoDB operations
  schemas/
    standup.ts          # Zod schemas for responses, config, digest
    slack-events.ts     # Zod schemas for Slack event payloads
  lib/
    config.ts           # Environment variable validation
    constants.ts        # Shared constants (limits, TTLs, timeouts)
    date.ts             # Timezone-aware date helper
    format.ts           # Slack Block Kit message builders
    llm-parser.ts       # Shared LLM response parser
    logger.ts           # Structured JSON logger
    prompts.ts          # LLM prompt templates
  types/
    index.ts            # Shared type definitions
infra/
  bin/app.ts            # CDK app entry point
  lib/standup-bot-stack.ts  # CDK stack
scripts/
  setup-local-db.ts     # Create local DynamoDB table
  seed.ts               # Seed sample team config and responses
  local-invoke.ts       # Invoke handlers locally
tests/
  handlers/             # Handler unit tests
  services/             # Service unit tests
  fixtures/             # Test data

Setup

Prerequisites

• Node.js 24.x
• AWS account with CDK bootstrapped
• Slack workspace with admin access
• Docker (for local development)

Install

npm install

Environment variables

Variable	Required	Default	Description
SLACK_BOT_TOKEN	Yes		Bot OAuth token (xoxb-...)
SLACK_SIGNING_SECRET	Yes		Slack app signing secret
DYNAMODB_TABLE_NAME	Yes		Set automatically by CDK
LLM_PROVIDER	No	claude	claude or ollama
ANTHROPIC_API_KEY	When claude		Claude API key (sk-ant-...)
OLLAMA_BASE_URL	When ollama	http://localhost:11434	Ollama server URL
OLLAMA_MODEL	When ollama	qwen3:8b	Ollama model name
DYNAMODB_ENDPOINT	No		Set for local DynamoDB

Slack app setup

1. Create a new Slack app at https://api.slack.com/apps
2. Add bot scopes: chat:write, im:write, im:read, im:history, users:read, reactions:write
3. Subscribe to events: message.im
4. Set the request URL to your API Gateway endpoint: https://{api-gw-url}/slack/events
5. Install the app to your workspace
6. Invite the bot to the digest channel

Deploy

Store secrets in SSM Parameter Store as SecureString:

aws ssm put-parameter --name /standup-bot/slack-bot-token --type SecureString --value "xoxb-..."
aws ssm put-parameter --name /standup-bot/slack-signing-secret --type SecureString --value "..."
aws ssm put-parameter --name /standup-bot/anthropic-api-key --type SecureString --value "sk-ant-..."

Then deploy:

npm run build       # Bundle with esbuild
npx cdk bootstrap   # First time only
npx cdk deploy      # Deploy stack

Local development

Start local services

npm run local:db      # Start DynamoDB Local (Docker) + create table
npm run local:seed    # Seed sample team config and responses

Run handlers locally

npm run local:prompt  # Send standup DMs (needs real Slack token)
npm run local:digest  # Generate digest (needs Slack token + LLM)
npm run local:event   # Simulate a Slack event

Use Ollama for local summarisation

ollama pull qwen3:8b
LLM_PROVIDER=ollama npm run local:digest

Run tests

npm test              # Run tests
npm run test:watch    # Watch mode
npm run test:coverage # Coverage report
npm run synth         # CDK synth (dry run)

Cost estimate

For a small team (5-10 members):

Service	Monthly cost
Lambda	< $1
DynamoDB	< $1
API Gateway	< $1
Claude Haiku	~$0.50
Total	< $5

DynamoDB records auto-expire after 90 days via TTL.