Scheduler

A group meeting scheduler with weighted availability and real-time aggregation. Create an event, share the link, and find the best time for everyone.

How to Use

1. Create an Event

Go to the home page and fill out the event form:

• Event Name — give your meeting a title
• Organizer Password — secures access to the organizer dashboard
• Meeting Type — In-Person (requires a location) or Virtual
• Time Range — set the start and end hours to consider
• Days — pick which days of the week are options (defaults to Mon-Fri)

After creating, you'll be redirected to the organizer dashboard.

2. Share the Link

Click Copy Share Link in the top-right corner to get a link like:

https://yoursite.com/event?code=j9eaFNJH

Send this to everyone who should participate. No account or sign-up needed.

3. Participants Fill In Availability

Each participant:

1. Enters their name and clicks Join
2. Uses the Availability Slider to pick a level (0 = Busy, 1 = Free, with 0.25 steps)
3. Clicks and drags on the schedule grid to paint time slots with that availability level
4. Clicks Submit Schedule when done

The grid uses color coding: red (busy) -> yellow (partial) -> green (free).

After submitting, participants can see the Group Availability table showing aggregated scores, plus each person's Individual Schedule below it.

4. Organizer Dashboard

Access the organizer view by appending &manage=<password> to the event URL. The organizer can:

• Set their own availability on the same grid
• Adjust participant weights (0.0-1.0) — higher weight means more influence on the group average
• Include/exclude participants from the aggregate calculation
• Remove participants from the event
• View the weighted group average in real time, updated as weights change

The weighted average formula: for each time slot, sum(availability * weight) / sum(weights) across all included participants.

Tech Stack

Layer	Technology
Frontend	Next.js 15 (App Router) + React 18 + Material Web components
Backend	Express 5 (ESM)
Database	DynamoDB (events, participants, weights tables)
Infrastructure	AWS ECS Fargate behind ALB (path-based routing)
IaC	Terraform (S3 remote state + DynamoDB lock)
CI/CD	GitHub Actions (lint, test, build, Docker build check, staging deploy)

Project Structure

scheduler-monorepo/
  frontend/         # Next.js 15 — UI only, no API routes
  backend/          # Express 5 — API server, DynamoDB
  infra/
    prod/           # Production Terraform (single ECS service, disabled)
    staging/        # Staging Terraform (2 ECS services, ALB path routing)
    bootstrap/      # Terraform state backend setup
  scripts/
    quality-gate.sh # Full lint + test + build for both workspaces
  .github/workflows/
    ci.yml          # Parallel CI for both workspaces
    deploy-staging.yml

Local Development

npm install          # install all workspace dependencies
npm run dev          # start backend (4000) + frontend (3000)
npm run dev:backend  # backend only
npm run dev:frontend # frontend only

The frontend proxies /api/* requests to http://localhost:4000 in dev via next.config.js rewrites.

Run checks:

npm --workspace=backend run lint
npm --workspace=frontend run lint
npm --workspace=backend run test   # 61 tests
npm --workspace=frontend run test  # 9 tests
npm --workspace=frontend run build
npm run quality-gate               # all of the above

Runtime Environment Variables

Backend

• PORT (default: 4000)
• AWS_REGION (default: us-west-2)
• DDB_EVENTS_TABLE (default: scheduler-prod-events)
• DDB_PARTICIPANTS_TABLE (default: scheduler-prod-participants)
• DDB_WEIGHTS_TABLE (default: scheduler-prod-weights)

Frontend

• NEXT_PUBLIC_API_BASE_URL — API base URL (empty = relative paths via proxy)
• BACKEND_URL — dev proxy target (default: http://localhost:4000)

Docker

# Backend
docker build -t scheduler-backend:local ./backend
docker run --rm -p 4000:4000 \
  -e AWS_REGION=us-west-2 \
  -e DDB_EVENTS_TABLE=scheduler-staging-events \
  -e DDB_PARTICIPANTS_TABLE=scheduler-staging-participants \
  -e DDB_WEIGHTS_TABLE=scheduler-staging-weights \
  scheduler-backend:local

# Frontend
docker build -t scheduler-frontend:local ./frontend
docker run --rm -p 3000:3000 scheduler-frontend:local

Deployment

Staging

Staging deploys automatically via deploy-staging.yml after CI passes on main. Architecture:

• ALB routes /api/* to backend ECS service, everything else to frontend
• 2 ECS Fargate services (backend on port 4000, frontend on port 3000)
• 3 DynamoDB tables with scheduler-staging- prefix

Production

Production workflows are disabled (.yml.disabled suffix). Cutover from the monolith is planned separately.

GitHub Actions Variables

• AWS_REGION — us-west-2
• AWS_ROLE_ARN — OIDC deploy role ARN
• ECR_STAGING_BACKEND — scheduler-staging-backend
• ECR_STAGING_FRONTEND — scheduler-staging-frontend