BulkReach
Multi-tenant bulk & scheduled messaging for Slack and WhatsApp
In short: BulkReach is an in-house DanixSoft product (SaaS / Communications): Multi-tenant bulk & scheduled messaging for Slack and WhatsApp. It is built and operated by the DanixSoft studio.
A multi-tenant SaaS for sending bulk and scheduled messages to Slack workspaces and WhatsApp numbers, with a dashboard, a marketing site and a separate always-on messaging service.
- Industry
- SaaS / Communications
- Scope
- Products we build and run in-house at DanixSoft
- Core stack
- Next.js 16 · TypeScript · Supabase · PostgreSQL
- Year
- 2026
The problem
Teams announcing to many Slack channels or WhatsApp contacts need sends that respect rate limits, survive timeouts, keep each customer’s data isolated, and never message people who haven’t opted in.
The solution
Every send becomes a queue of per-recipient delivery rows, drained under each platform’s rate limits — right after a send and by a Postgres cron job every minute — so interrupted campaigns resume instead of restarting.
DanixSoft team
An in-house DanixSoft product — built and operated by the studio, not for a client.
Technical challenges
The engineering problems this build had to get right.
- Tenant isolation in every RLS policy, plus an audit query that must return zero rows
- Tokens and messaging sessions encrypted at rest (AES-256-GCM)
- Randomised spacing and a hard floor between WhatsApp messages
Architecture
Implementation — what shipped
Engineering notes
Lesson for similar SaaS builds: design for tenant isolation in every RLS policy, plus an audit query that must return zero rows and tokens and messaging sessions encrypted at rest (AES-256-GCM) up front — these are the parts that are expensive to retrofit once the feature list grows.
Technologies
- Next.js 16
- TypeScript
- Supabase
- PostgreSQL
- Slack API
- Node.js
- Vitest
Building something similar?
A 30-minute discovery call is enough to scope the approach and a realistic budget.