EchoCue
EchoCue is a programmable SMS and WhatsApp automation platform that businesses use to send scheduled reminders, follow-ups and notifications through a dashboard, a REST API or no-code integrations
EchoCue is a SaaS messaging platform I designed and built for scheduled, multi-channel outbound communication. At its core it handles the hard parts of business messaging - contact management, reusable templates with variables, scheduled and recurring broadcasts, workflow automations, delivery tracking, per-message cost accounting and a metered credit wallet - and exposes all of it through three surfaces: a web dashboard for non-technical users, a REST API with OpenAPI documentation for developers, and prebuilt Zapier, Make, and n8n integrations for teams that live in no-code tooling. That model means the same platform powers very different use cases. Today the go-to-market is focused on service businesses using it for appointment reminders and payment follow-ups - with Google Calendar sync, industry-tuned landing pages, and workflow presets for verticals like dental, veterinary, auto, and personal care - but the underlying system is industry-agnostic. Anything that needs to send a scheduled message to a contact based on an event, a schedule, or an API call can be built on it: fintech transaction alerts, logistics status updates, healthcare adherence nudges, marketing broadcasts, internal notifications. Businesses can send from EchoCue's shared infrastructure or connect a personal device for unlimited sending. I built the whole stack: a Node.js/Express API on MySQL with SQS-backed workers on AWS; Stripe subscription billing with a credit model; Twilio SMS and WhatsApp Business API delivery; Google OAuth and Calendar integration; Firebase push for the mobile companion; and the entire frontend - marketing site, user dashboard, and admin console - in vanilla HTML/JS with Tailwind. Product design, UX, copy, system architecture, and API design are all mine.
Stack
Recent updates
20 total- Stripe recurring billing - full subscription lifecycle, refund + renewal handling, admin controls to end already-refunded subscriptions, yearly plans, plan-feature flags (can-send-links, unified-inbox), and onboarding capture of industry/persona.
- Team accounts + sub-accounts - invites, member permissions, ownership transfer, downgrade-with-overcount enforcement, and a unified WhatsApp inbox across sub-accounts.
- Meta billing integration - dashboard billing banner, nightly billing checks, and diagnostic status endpoint.
- WhatsApp pre-send safety - block gates on all send paths, official Meta health-check integration for device status, device-level failure flagging.
- WhatsApp template lifecycle - Meta template-library integration with named/positional parameters, self-healing sync, status webhook, quality-rating banner, per-template analytics, and a visual button builder.
- Multi-WABA architecture - per-workspace WABA isolation, helper functions, send-template WABA matching, orphan template reconciliation, cascade on device delete.
- WhatsApp Business onboarding - Meta tech-provider flow via Embedded Signup v4 (drop-in OAuth, coex/SMB path handling).
- Workspace/tenancy foundation - workspace status enforcement, environment checks, security hardening, and workspace stats endpoints.
- Multi-vertical marketing site - 15 industry-specific landing pages, FAQ/pricing schema for AI citation, OG/Twitter images, llms.txt.
- Calendar health monitoring - issue-detection pipeline with email + push notifications and self-diagnosis prompts.
- Calendar-driven workflow engine - channel-aware workflow tabs, per-template rules, and reminder cleanup on channel/device changes.
- Google Calendar integration - OAuth linking, appointment sync, manual refresh, and reminder wizard.
- Device management - personal-device sending, device logs, and extended FCM push retry (~3h window) for mobile background fallback.
- Notification logging + filters - delivery-log modal, per-status filters, and refreshable delivery views.
- Projects module - filters, bulk actions, duplicate functionality, and organization-level grouping.
- Contacts module - import, filters, bulk actions, bulk-delete confirmation, and opt-out honored on calendar-triggered sends.
- Team collaboration in inbox - multi-user assignment, notes on messages, consent tags, and an audit log.
- Conversational inbox - threaded replies, in-thread search, message actions, and a premium UI pass.
- Template system - reusable templates with variables, quick replies, media attachments, and message-level actions.
- Core messaging engine - SMS broadcast creation, scheduling, contact-list targeting, per-message delivery tracking.