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Primary Inbox.

Cold-email infrastructure that scales without burning domains.

YEAR
2025
ROLE
Full-Stack Engineer
STACK
REACT · NEXT · TS · NEST · BULLMQ · REDIS · MONGODB
LINK
Live ↗
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01 PROBLEM

Scaling cold email campaigns often leads to burned domains and chaotic lead management. The core tension is maximizing outreach volume and deliverability without damaging sender reputation or losing track of replies across fragmented inboxes.

02 SOLUTION

Built the platform with React + Next.js + TypeScript on the front and a Nest.js backend coordinated by BullMQ and Redis to manage high-volume email queues without overrunning per-mailbox sending limits. Configured custom mail servers and the underlying MongoDB schema, integrated payment gateways for the subscription tier, and stitched in IMAP/SMTP connections so users can plug in their own provider mailboxes safely.

03 OUTCOME

Launched a comprehensive outreach engine that empowers up to 1,000 users to automate lead generation, maintain optimal sender reputation, and close deals through a single centralized dashboard.

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