Stars
Forks
Watchers
Developer links
Plunk
Plunk consolidates transactional emails, marketing campaigns, and drip automation into one platform riding AWS SES at roughly one-tenth of a cent per message, with zero per-contact charges regardless of list size. The Turborepo monorepo architecture separates the Express.js API server (handling REST requests with Prisma ORM against PostgreSQL) from a dedicated BullMQ worker process that consumes email, campaign, and workflow jobs independently for fault isolation and horizontal scaling. Transactional emails support HTML bodies, template variable substitution via React Email components, attachments, and custom headers with dedicated SMTP relay on ports 465 and 587 for integration with existing frameworks. The campaign system sends newsletters and product updates to full contact lists or dynamically segmented audiences based on contact properties and behavioral events, with scheduling, A/B testing, and performance tracking for opens, clicks, and bounces. The workflow automation builder creates event-triggered sequences with delays, conditional branches, and webhook steps for lifecycle campaigns like onboarding drip sequences and re-engagement flows. Contact management stores unlimited contacts with custom data fields, CSV import, full activity history, and dynamic segmentation. Custom domain verification with DKIM and SPF ensures deliverability, while inbound email processing handles incoming messages with custom routing rules. Docker Compose deployment runs five containers including PostgreSQL, Redis, MinIO for S3-compatible storage, and ntfy for notifications. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.
Benefits
- Unified Transactional and Marketing Email
- Single platform handles API-triggered transactional emails, broadcast marketing campaigns, and event-driven workflow automations with shared contact management, analytics, and domain verification instead of separate services.
- AWS SES Cost Efficiency
- Built directly on Amazon SES for email delivery at approximately $0.001 per email with no contact limits, eliminating per-seat pricing and volume tiers that inflate costs on competing platforms.
- Scalable Worker Architecture
- BullMQ job queues on Redis decouple the Express.js API server from email processing, allowing worker processes to scale independently with retry logic, rate limiting, and concurrency control.
- Developer-First API and SDKs
- REST API with Node.js, Python, and Dart SDKs enables programmatic email sending, contact management, event tracking, and campaign creation from any language capable of HTTP requests.
Features
- Workflow Automation Builder
- Event-triggered email sequences with configurable delays, conditional branches based on contact properties, and webhook steps for lifecycle campaigns and onboarding drip flows.
- React Email Templates
- Code-based email templates using React Email components with variable substitution, attachments, and custom headers for consistent transactional and marketing message design.
- Dynamic Contact Segmentation
- Unlimited contact storage with custom data fields, CSV import, full activity history, and dynamic segment creation based on contact properties and behavioral event tracking.
- SMTP Relay Server
- Built-in SMTP server on ports 465 and 587 enables sending through Plunk from any existing application, framework, or tool without API integration code changes.
- Real-Time Email Analytics
- Dashboard tracking for opens, clicks, bounces, complaints, and custom events in real time with data feeding back into workflow triggers and audience segments.