Full Stack Developer (JuniorIntermediate)

Full Stack Developer
Junior / Intermediate

About Reactiv

Reactiv is an AI-powered platform that helps Shopify merchants build beautifully branded
high-converting mobile apps without the usual complexity. At the core of what we do is
Reactiv Clips a feature that removes the need for app downloads so brands can deliver
fully customized app experiences instantly and without friction. By lowering the barrier to
great mobile experiences were building the future of mobile commerce and were
growing our engineering team to help shape what comes next.

About the Role

Were looking for a Junior to Intermediate Full Stack Developer to help build and improve
the platform our merchants rely on every day from the dashboard they use to design and
manage their apps to the e-commerce APIs that power them. Youll ship real features
from early on with support and mentorship from our engineering team to help you grow.
Most of your work will be in TypeScript across React on the frontend and on the
backend with the chance to go deeper on whichever side excites you most. This is a
hands-on role for someone earlier in their career who wants to develop into a strong full
stack engineer in a collaborative hybrid environment. You dont need to check every box
below; if youre solid on the fundamentals and eager to learn the rest we want to hear
from you.

What Youll Do

Build and maintain features across our merchant dashboard React and
TypeScript) and our backend services and e-commerce APIs and
TypeScript).
Write and consume RESTful and GraphQL APIs that connect our frontend
experiences to server-side functionality.
Work with relational databases such as Postgres: designing simple schemas
writing queries and learning optimization along the way.
Contribute to our Shopify integrations that keep merchant data in sync.
Collaborate with product design and other engineers to define design and ship
new features.
Help keep the platform fast and reliable by improving performance and
responsiveness on both sides of the stack.
Take part in code reviews both giving and receiving feedback as part of how we
maintain quality.
Troubleshoot and fix issues across the stack to improve the experience for
merchants.

What Were Looking For

Working knowledge of React and a solid grasp of its core concepts.
Some experience building backend services or APIs with .
Comfortable writing TypeScript or strong JavaScript with a willingness to pick up
TypeScript quickly.
An understanding of how frontend and backend talk to each other: RESTful APIs
requests responses and error handling.
Familiarity with relational databases such as Postgres or MySQL.
Strong problem-solving instincts and eagerness to learn in a fast-moving
collaborative team.
Roughly 2 to 4 years of experience building web applications or equivalent project
and portfolio work.

Nice to Have

Experience with GraphQL.
Familiarity with the Shopify ecosystem or an interest in ecommerce.
Exposure to AWS services Lambda S3 RDS DynamoDB or other cloud
infrastructure.
Experience with a React framework such as or React Router (formerly
Remix).
Experience writing automated tests Jest React Testing Library or integration
tests).
Understanding of authorization concepts such as OAuth and JSON Web Tokens.
Familiarity with CI/CD practices.
Exposure to React Native or interest in contributing to mobile.

Why Join Us

Mentorship and growth: Youll have regular code review pairing and support from
experienced engineers with a clear path from junior to intermediate and beyond.
Level up with AI Were constantly exploring how AI can make us better engineers
and youll have real freedom to experiment with cutting-edge tools rather than wait
for permission. Its a fast way to grow.
Real impact: The features you build are used by merchants running their
businesses around the world.
Hybrid work environment: We believe in a hybrid model to create opportunities for
intentional in-person collaboration (and mentorship) while balancing that with the
deep focus time that comes from working remotely. Youll join the team in our
Toronto office 2 to 3 days a week with the flexibility to work remotely the rest of
the time.
Youre an owner: Every engineer at Reactiv gets equity so you share in the upside
you help create. Youre not just building the product you own a piece of it.
Benefits from day one: Extended health and dental coverage that kicks in the day
you start no waiting period.
Unlimited PTO We take time off seriously here. Most of our engineers take around
three weeks a year and more when they need it and we actively encourage
stepping away to rest and protect against burnout.

How to Apply

Send your resume and any project links portfolio or GitHub profile to
A cover letter is optional but wed welcome a short note on why this role interests you.

Required Experience:

Junior IC