Senior Backend Engineer

1 week ago

Toronto, Ontario, Canada Skyfire Full time $120,000 - $180,000 per year

About Skyfire
Skyfire is building the payment backbone for the emerging machine economy — a future where AI and machines transact seamlessly, instantly, and autonomously. Current financial systems aren't designed for this, so we're creating one that is.By leveraging stablecoins and blockchain technology, Skyfire enables instant, global micropayments between AI, APIs, data providers, and services. Enterprises can also automate microtransactions at scale — all with speed, security, and transparency. Our team brings deep experience in payments, fintech, and distributed systems — and we're moving fast to define how the machine economy will pay for itself.

Why This Role Matters

As a Backend Engineer at Skyfire, you'll be building the infrastructure that powers high-speed, high-volume machine-to-machine payments. From smart contract integrations to high-throughput APIs, you'll architect, code, and optimize backend systems that will scale from tens to thousands of requests per second. Your work will be critical in making AI-to-AI payments not just possible, but frictionless.

In This Role, You'll Get To:Design and develop core backend components, including smart contract integrations, payment processing logic, and APIs.
 Implement scalable blockchain solutions for on-chain machine payments with high throughput and low latency.
 Collaborate closely with product to translate requirements into robust, maintainable technical solutions.
 Optimize performance for speed, scalability, and cost-efficiency across distributed systems.
 Mentor junior engineers and foster a culture of technical excellence and innovation.
 Stay ahead of the curve on blockchain, smart contracts, and AI technologies — integrating them where they create real impact.
 We're Excited About You Because You Have:A self-starter mindset and the drive to tackle big challenges head-on.
 Strong TypeScript proficiency and backend development expertise.
 Experience with PostgreSQL or MySQL and sound database design skills.
 Solid system design skills to scale from 10s to 1000s of RPS.
 Familiarity with CI/CD, Kubernetes, and Docker for smooth build and deployment.
 Experience with cloud infrastructure (AWS, GCP, or Azure) — including networking fundamentals like load balancers and firewalls.
 Strong skills in testing, debugging, and reliability engineering.Bonus Points If You Have:Experience with REST or GraphQL APIs (design + integration).
 Knowledge of OAuth 2.0, OpenID Connect, SSO, and RBAC.
 Understanding of time complexity and system performance optimization.
 Familiarity with NoSQL / Key-Value Stores.
 Awareness of security best practices for authentication, authorization, and encryption.
 Web3 / blockchain experience — especially smart contracts and dApps.
 Why You'll Love Working Here:Competitive cash + equity package — we believe in rewarding impact.
 Healthcare coverage for you and your family.
 Fast-growth startup environment — with real ownership from day one.
 Collaborative, high-impact culture — where innovation and execution thrive.
 Shape the future — play a key role in how AI and machines transact globally.

Interview Process

Recruiter ScreenWoven AssessmentHiring Manager ScreenLive CodingSystem DesignCommitment Interview

  • Senior Backend Engineer

    6 days ago

    Toronto, Ontario, Canada LotusFlare Full time $120,000 - $180,000 per year

    LotusFlare is a provider of cloud-native SaaS products based in the heart of Silicon Valley. Founded by the team that helped Facebook reach over one billion users, LotusFlare was founded to make affordable mobile communications available to everyone on Earth.Today, LotusFlare focuses on designing, building, and continuously evolving a digital commerce and...

  • Senior Java Backend Engineer

    2 weeks ago

    Toronto, Ontario, Canada Flexton Inc. Full time $120,000 - $180,000 per year

    Job Title:Java Backend Engineer (API & Messaging Queues)Location:Toronto, CA-Hybrid (1 day onsite)Experience: 8+ YearsAbout the Role:We are looking for aSenior Backend Engineerto join our client inToronto(Hybrid). In this role, you will design, develop, and maintainJava-based backend services, includingRESTful APIsand integrations withmessaging systemslike...

  • Backend Engineer

    5 hours ago

    Toronto, Ontario, Canada Blackbird Lab Full time $80,000 - $120,000 per year

    Who we areBlackbird Lab is a software development company. While we are practicing international working culture, we are proud representatives of Ukrainian values and traditions. We are a team of 90+ energetic, curious, smart, and open to new challenges tech pros who prefer efficient async communication, flexible working hours, a co-working office model,...

  • Senior Backend Engineer II

    7 hours ago

    Toronto, Ontario, Canada Mistplay Full time US$120,000 - US$180,000 per year

    Mistplay is the #1 loyalty app for mobile gamers. Our community of millions of engaged mobile gamers come to Mistplay to discover new games to play and earn rewards. Gamers are rewarded for their time and money spent within the games and can redeem those rewards for gift cards. Mistplay is on a mission to be the best way to play mobile games for everyone...

  • Senior Backend Engineer II

    25 minutes ago

    Toronto, Ontario, Canada Mistplay Full time US$180,000 - US$250,000 per year

    Mistplay is the #1 loyalty app for mobile gamers. Our community of millions of engaged mobile gamers come to Mistplay to discover new games to play and earn rewards. Gamers are rewarded for their time and money spent within the games and can redeem those rewards for gift cards. Mistplay is on a mission to be the best way to play mobile games for everyone...

  • Senior Backend Engineer

    1 week ago

    Toronto, Ontario, Canada Aquanow Full time $120,000 - $180,000 per year

    About usAquanow is a trading and technology company powering the next generation of financial services. We're at the forefront of the rapidly evolving digital asset space, empowering businesses to navigate the complexities of cryptocurrencies and blockchain technologies. As a leading provider of infrastructure solutions, we offer innovative services in...

  • Senior Backend Engineer

    3 days ago

    Toronto, Ontario, Canada NimbleRx Full time $120,000 - $180,000 per year

    Nimble is a healthtech company on a mission to simplify access, understanding and management of healthcare. We are starting by building the largest, most loved pharmacy business in the world. We are a fast-growing, technology-first startup driven by perfecting the patient and pharmacist experience. Nimble fosters a culture of collaboration, open...

  • Backend Engineer

    2 weeks ago

    Toronto, Ontario, Canada integral Full time $120,000 - $180,000 per year

    Location: Toronto (Liberty Village) Preferred | Open to Remote in Canada Type: Full-Time, Permanent About Integral Integral is building the foundation for AI-enabled financial operations, trusted by customers to manage their business ledgers and provide mission-critical financial insights. The company's core values are proactivity, short feedback loops, an...

  • Senior Backend Developer

    2 days ago

    Toronto, Ontario, Canada Initiate International Full time US$1,200,000 - US$2,400,000 per year

    Help build the engine behind a high-growth iGaming and sports betting platform.Our client is investing heavily in technology to create a world-class betting and gaming experience – real-time markets, instant payouts, and a seamless journey for players.They are looking for aSenior Backend Developerwho thrives on complex systems, high traffic, and the...

  • Senior Backend Engineer

    1 week ago

    Toronto, Ontario, Canada Inspiration Commerce Group Full time $120,000 - $180,000 per year

    About Inspiration Commerce Group (ICG)We're a team of ~25 people who've done 6 acquisitions in 18 months and scaled from $0 to >$75M in revenue. We're a global group with businesses across the US, UK, and EU. We buy and build companies that help people find and buy the products they love. Our portfolio includes leading fashion marketplaces like Italist and...