Senior Software Engineer

SalesJack•Toronto, ON

15d•CA$180,000 - CA$200,000•Onsite

About The Position

SalesJack is a fast-growing, profitable sales software platform (CRM, Prospecting Service) purpose-built for independent businesses in the construction supply industry. Our team and customers are spread across the US and Canada. Our mission: build tools that solve real problems for our customers and transform industry workflows. As a Senior Full Stack Software Engineer at SalesJack, you'll be one of the senior technical hires on the team - owning major product surfaces end-to-end. That means more than writing code: you'll talk to customers, scope what to build, make the product calls, and ship it. We don't have a PM layer between engineering and customers; the engineers closest to the problem own the solution. You'll partner directly with the founders and lead engineers to set architectural direction and raise the engineering bar while also bringing real product taste to the work. This is a hands-on role: writing production code daily, making the calls on what gets built and how it scales, and sweating the details of how it feels to use. We highly value a startup mentality. Strong opinions held loosely, fast iteration, and a bias toward shipping over deliberating.

Requirements

8–10 years of full stack engineering experience, including time spent owning systems in production at meaningful scale
Deep expertise in React and Next.js, with a strong point of view on component architecture, state management, and performance
Strong backend chops in Node.js — you've designed and operated services, not just built features inside them
Advanced PostgreSQL — schema design, query optimization, migrations under load, multi-tenant patterns
Production experience with auth/RBAC systems, especially in multi-tenant B2B contexts
Hands-on experience with BullMQ or comparable queue/job systems (Sidekiq, RabbitMQ, SQS, Temporal) — and a clear sense of when to reach for them vs. simpler patterns
A real product brain. You can be handed a fuzzy customer problem and come back with a scoped, shippable plan - not a Jira ticket asking for specs
Strong product taste. You push back on bad designs, come up with better ones, and have opinions about what "good" looks like in B2B software
Customer instinct. You actually want to talk to users, watch them work, and let what you learn shape the product. You don't need to be shielded from messy customer feedback
Ability to make tradeoff calls — what to cut, what to defer, what to over-invest in — without needing a PM to break the tie

Responsibilities

Own entire product features from "this is a problem worth solving" to "this is live in customers' hands" — scoping, designing, building, shipping, iterating
Talk to customers directly: discovery calls, support tickets, ride-alongs with sales reps in lumberyards. Use what you learn to make better product decisions
Make the architectural calls on new systems — data model, API surface, frontend composition — and document the reasoning so the team can build on it
Build across our Node.js stack: Next.js on the frontend, Node services on the backend, BullMQ for background jobs and workflows, PostgreSQL as the system of record
Design and operate authentication, authorization, and multi-tenant RBAC systems that hold up under real customer load
Build durable, queue-driven automation with BullMQ — orchestrating long-running processes, retries, and integrations against external ERPs and third-party APIs
Set technical standards (testing, code review, CI/CD, observability) and raise the bar for everyone around you, including the founders
Mentor engineers and lead design reviews