Senior Software Engineer Testing Frameworks in Toronto

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. Our core philosophy is to empower developers to self-serve rather than be bottlenecked by a central quality team. We believe that by creating smart, automated tooling, we can eliminate common roadblocks, making developers happier and more productive. The Rider Quality team is focused on elevating quality, testing, and accessibility across our mobile platforms. We are currently shifting our strategy to heavily leverage automation and AI to revolutionize how we approach testing. We're not doing traditional QA - we're building the future of quality engineering. This is a chance to step into a Senior role where you won't just write code; you'll design systems that define how hundreds of engineers deliver product faster, happier, and with fewer bugs. We are fundamentally shifting away from manual processes and existing automation frameworks that struggle to keep up, betting heavily on Artificial Intelligence and agentic frameworks to drive a massive "shift left" in our organization. Success in this role is measured by tangible impact, including increased developer satisfaction, engineering hours saved, and bugs/incidents avoided in production. We are seeking a highly skilled and innovative Senior Software Engineer to join our team. You will be instrumental in building the next generation of our quality assurance platform. You will be responsible for designing and developing advanced AI-powered tooling for test case generation, review, and execution. Your work will directly impact our ability to provide fast, actionable feedback to developers, "shifting left" to ensure quality from the earliest stages of development. You will play a key role in integrating these tools into our existing developer workflows, ensuring seamless adoption and maximum impact. We are looking for someone with a strong background in

Secure Every Identity, from AI to Human Identity is the key to unlocking the potential of AI. Okta secures AI by building the trusted, neutral infrastructure that enables organizations to safely embrace this new era. This work requires a relentless drive to solve complex challenges with real-world stakes. We are looking for builders and owners who operate with speed and urgency and execute with excellence. This is an opportunity to do career-defining work. We're all in on this mission. If you are too, let's talk. Auth0 is growing rapidly and looking for exceptional new team members to help take us to the next level. One team, one score. We never compromise on identity. You should never compromise yours either. We want you to bring your whole self to Auth0. If you're passionate, practice radical transparency to build trust and respect, and thrive when you're collaborating, experimenting and learning – this may be your ideal work environment. We are looking for team members that want to help us build upon what we have accomplished so far and make it better every day. N+1 > N. About the Team Here at Auth0 we’re focused on securing the world’s identities so innovators can innovate. We’re currently hiring a senior Full Stack Software Engineer to join our Acquisitions and Activation Team . This team owns the crucial first impressions of the Auth0 ecosystem. We apply rigorous, data-driven experimentation and A/B testing to optimize the entire early customer journey—from the moment a developer signs up, to the precise second they hit their "ah-ha" moment. We bridge the gap between deep technical infrastructure and user psychology, building primarily on a JavaScript ecosystem (Node.js and React) . If you are a full-stack engineer who loves blending robust software architecture with rapid, metrics-driven experimentation, this is the team for you. What You Will Do Optimize the Acquisition Funnel: Own, build, and continuously scale the entire signup experience to reduce fric

Who are we? Cohere is the leading security-first enterprise AI company. We build cutting-edge foundation AI models and end-to-end products that are designed to solve real-world business problems. We’re training and deploying frontier models for enterprises who are building AI systems. We believe that our work is instrumental to the widespread adoption of AI and we are looking for folks that want to be part of that. We obsess over what we build. Each one of us is responsible for contributing to increasing the capabilities of our models and the value they drive for our customers. Cohere is a team of researchers, engineers, designers, and more, who are all passionate about their craft. We are a global technology company headquartered in Toronto with key offices in London, New York City, San Francisco, Montreal, Paris, Berlin and Seoul. Join us! As a Senior Security Engineer you will: Serve as trusted advisor to team’s leadership and partner teams by clearly articulating business risks associated with security issues Lead security operation functions – including vulnerability management, SAST, DAST, detection engineering, and incident response – in CI/CD and cloud-native production environments Integrate security into our applications throughout the software development lifecycle Collaborate with product and development teams, driving the success of larger projects to ensure that software is built and deployed securely without compromising agility and speed Driving and supporting bug bounty program, application security reviews and threat modeling, including code review and dynamic testing Assess and integrate security tools to automate and scale security processes, i.e: evaluate open-source vs vendor solutions Gather and analyze security metrics to address security issues with cross-team dependencies Be a problem solver who is empathetic to developer concerns and will employ constructive and flexible approach to building innovative solutions You may be a good fit if: 5

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. Lyft is looking for software engineers from a scope of disciplines. We are growing our team with people who want to build, improve and incorporate technologies that make the lives of our community more enriched. As an engineer at Lyft, you'll collaborate with teams like product, data science, analytics, and operations on code that empowers us to iterate quickly, while focusing on delighting our passengers and drivers. The Applied AI team is looking for a senior software Engineer to join the Recommendations team. You will build the backend systems that decide what we surface to riders. You will architect the pipelines and services that turn rider context and signals into the right offer at the right moment, driving a measurable impact on rider experience. Responsibilities: Establish engineering best practices and patterns; help uplift the team's craft and drive a culture of engineering excellence Drive high-impact projects and innovate new solutions to deliver the best user experience Produce and drive scalable system design for large, complex features — from idea through execution and launch Mentor engineers on the team, providing technical guidance and supporting their growth Champion and evangelize the use of AI tools to accelerate engineering productivity across the team, sharing patterns and best practices that raise the bar for how the team builds Write well-crafted, well-tested, readable, maintainable code Participate in code reviews to ensure code quality and share knowledge across the team Participate in the team's on-call rotation; identify, triage, debug, and resolve issues across our applications and platforms Excellent communication skills and the ability to explain the various trade offs made in decisions Manage project priorities, deadlines, and deliverables. Experience: BS/MS or

At Vanta, our mission is to help businesses earn and prove trust. We believe that security should be monitored and verified continuously, and we empower companies to practice better security and prove it with ease. Vanta has a kind and talented team, and while some have prior security experience, many have been successful at Vanta without it. We are looking for a Senior Software Engineer to join our Product Platform org - the group that powers product development across Vanta by building the shared foundations that every engineering team builds on top of. This hire will join one of two closely-aligned teams within the org, each working on foundational challenges with company-wide impact. Application Primitives is responsible for the shared, customer-facing platform components that product teams implement across the product: examples include comments, notifications platform, event log infrastructure, and agentic audit trails. This team sits at the intersection of platform and product - not pure infrastructure, not pure product - building the reusable building blocks that let other teams ship faster and more consistently. Libraries & Foundations is a brand-new team that owns Vanta's internal engineering libraries and golden-path patterns. Sitting between core platform and product platform in the stack, this team builds the TypeScript-first abstractions and shared foundations that all Vanta engineers build on top of - including event-driven architecture libraries, code quality tooling, and test frameworks. You'll be evaluated for both teams based on your background and interests, and the decision on team placement will reflect where your skills and passions are the strongest fit. Visit our Vanta Engineering Blog to learn more about what our team is working on! What you’ll do as a Senior Software Engineer, Product Platform at Vanta: Design and build high-quality, scalable systems and shared libraries that multiple engineering teams depend on - whether that's shared

Who are we? Cohere is the leading security-first enterprise AI company. We build cutting-edge foundation AI models and end-to-end products that are designed to solve real-world business problems. We’re training and deploying frontier models for enterprises who are building AI systems. We believe that our work is instrumental to the widespread adoption of AI and we are looking for folks that want to be part of that. We obsess over what we build. Each one of us is responsible for contributing to increasing the capabilities of our models and the value they drive for our customers. Cohere is a team of researchers, engineers, designers, and more, who are all passionate about their craft. We are a global technology company headquartered in Toronto with key offices in London, New York City, San Francisco, Montreal, Paris, Berlin and Seoul. Join us! About the role. We’re building the next generation of agentic AI infrastructure at Cohere. This team sits at the intersection of ML systems, distributed infrastructure, and developer experience, creating the platform that powers autonomous AI agents at scale. You’ll work on hard, forward-looking problems with few established patterns, including secure code execution, agent state management, model routing, identity and authentication, and resource management for long-running agent workflows. This role is a strong fit for someone who combines systems depth with ML intuition. You should be comfortable building reliable infrastructure, thinking through distributed systems tradeoffs, and understanding how emerging agentic capabilities shape platform design. What you’ll work on. Secure execution environments for agent-generated code Identity, authentication, and trust boundaries for agents Model routing and orchestration across different model types and environments Rate limiting, quotas, and resource management for agent workflows State management, memory, and filesystem abstractions for agents. In this role you will: Turn emerging M

Who are we? Cohere is the leading security-first enterprise AI company. We build cutting-edge foundation AI models and end-to-end products that are designed to solve real-world business problems. We’re training and deploying frontier models for enterprises who are building AI systems. We believe that our work is instrumental to the widespread adoption of AI and we are looking for folks that want to be part of that. We obsess over what we build. Each one of us is responsible for contributing to increasing the capabilities of our models and the value they drive for our customers. Cohere is a team of researchers, engineers, designers, and more, who are all passionate about their craft. We are a global technology company headquartered in Toronto with key offices in London, New York City, San Francisco, Montreal, Paris, Berlin and Seoul. Join us! Why This Role? Ready to build AI agents that revolutionize enterprise security? The North Security team is looking for a Senior Software Engineer to create autonomous systems that handle the complex, critical tasks security practitioners face every day. Your Role: As a Senior Software Engineer focused on agentic security, you'll build intelligent systems that empower security teams. Your responsibilities will include: Build autonomous security agents that perform alert triage, secure code reviews, threat modeling, and vulnerability assessment Develop agent orchestration systems that help security practitioners automate repetitive security tasks Design and implement agent security controls to ensure our AI agents can safely interact with sensitive enterprise data Create the security infrastructure that allows agents to operate in high-trust environments with stringent deployment requirements Ship production-ready agent capabilities that run efficiently in resource-constrained environments Research and implement novel security patterns for AI agent systems, sometimes requiring custom solutions where standard libraries fall short C

About Sentry Software runs the world and the pace is faster than ever. Sentry helps developers fix errors and performance issues before users notice, so teams can spend less time firefighting and more time building. Trusted by 200,000+ organizations, Sentry is today’s application monitoring standard and our team is building its AI-native future. Ready to build the future of mobile app monitoring? This is no ordinary engineering role. At Sentry, our Mobile SDK team creates the next generation of tools for developers worldwide, processing over a billion events every single day. We're looking for a talented Senior iOS SDK Engineer to join our team of experts. You'll dive deep into Apple's most advanced technology, from powerful new APIs and SwiftUI to Foundation Models. If you love using cutting-edge tech to solve complex challenges, you've found your team. What you will achieve in this role As the owner of our iOS SDK, you will guide its development from the core architecture to the final product experience. You'll pioneer exciting new features like Session Replay and next-generation performance monitoring, all while mastering Apple's latest innovations like modern concurrency and on-device AI. You will design robust, high-quality APIs built to handle massive scale, and you'll get to shape the overall vision for mobile at Sentry. Ultimately, you will be the go-to expert, helping our teams solve the most complex and interesting customer challenges. Why you will love this role We're looking for someone who is passionate about their craft and loves building elegant, intuitive tools that other developers are excited to use. You'll have the chance to contribute full-time to a major open-source project and see the immediate impact of your work in our fast-paced environment. You will be surrounded by thoughtful, collaborative engineers who are dedicated to a culture of excellence, constantly pushing each other to learn, grow, and produce their best work. Qualifications 5+ ye

About Sentry Software runs the world and the pace is faster than ever. Sentry helps developers fix errors and performance issues before users notice, so teams can spend less time firefighting and more time building. Trusted by 200,000+ organizations, Sentry is today’s application monitoring standard and our team is building its AI-native future. About the role The Events Analytics Platform (EAP) team is responsible for the infrastructure that powers all of Sentry's time-series data and searching capabilities across billions of events with sub-second latency. We started this initiative by building Snuba, the primary storage and query service for Sentry's event data powered by ClickHouse, and we are now focused on unlocking deeper visibility and reporting across the terabytes of event data our users generate. As a Senior Software Engineer, you will lead efforts to push the boundaries of data visibility at Sentry. You will do this by expanding the capabilities of our search infrastructure, building new capabilities on top of our state-of-the-art storage layer and increasing the performance and integrity of Sentry’s core data services. You will also help shape Infrastructure's technical direction at Sentry and collaborate with Product and other Engineering teams to turn that vision into a reality. If you want to solve the hard problems that come with scaling event data into the petabyte range, this could be the job for you. In this role you will: Expand EAP's ability to deliver data at world-class speed and reliability. Architect and automate services and systems to scale reliably under growing demand. Make architectural trade-offs that balance product requirements with engineering constraints. Maintain and grow the team's code quality initiatives by regularly reviewing code and contributing to design decisions. Lead design and discussions around deliverables the team is working towards. Improve the maintainability and developer experience of the codebases EAP owns. Exa

About Sentry Software runs the world and the pace is faster than ever. Sentry helps developers fix errors and performance issues before users notice, so teams can spend less time firefighting and more time building. Trusted by 200,000+ organizations, Sentry is today’s application monitoring standard and our team is building its AI-native future. About this role Are you ready to redefine the future of JavaScript development? Are you a seasoned JavaScript expert who gets a thrill from tackling complex challenges across the entire JavaScript ecosystem? Do you believe that AI can be a powerful partner in crafting elegant, high-impact code? If you're ready to leave the mundane behind and join a team that's shaping the tools used by millions of developers globally, we've got an opportunity for you at Sentry. This isn't your typical Senior Software Engineer position. As a key member of our growing JavaScript SDK team, you'll be at the forefront of innovation, working on everything from our cutting-edge SDKs for the React, Next.js, Vue, Nuxt, Hono, NestJS, and beyond. You won't just be maintaining code; you'll be pushing the boundaries of what's possible in developer tooling across the full spectrum of the modern JavaScript framework landscape. In this role you will Join our JavaScript SDK team and get ready to build the future. You'll be at the forefront, working on: A Universe of JavaScript Challenges: Dive deep into our extensive suite of JavaScript SDKs, with a broad focus on framework support spanning the modern JS ecosystem — from frontend frameworks like React, Vue, and their meta-frameworks Next.js and Nuxt, to server-side and edge runtimes like NestJS and Hono. Your work will directly empower millions of developers to build better, more reliable software, regardless of their framework of choice End-to-End Ownership: We believe in giving our engineers the autonomy to see their vision through. You'll have the freedom to plan, implement, and ship your code, from writi

About Sentry Software runs the world and the pace is faster than ever. Sentry helps developers fix errors and performance issues before users notice, so teams can spend less time firefighting and more time building. Trusted by 200,000+ organizations, Sentry is today’s application monitoring standard and our team is building its AI-native future. About this role Are you ready to redefine the future of JavaScript development? Are you a seasoned JavaScript expert who gets a thrill from tackling complex challenges across the entire JavaScript ecosystem? Do you believe that AI can be a powerful partner in crafting elegant, high-impact code? If you're ready to leave the mundane behind and join a team that's shaping the tools used by millions of developers globally, we've got an opportunity for you at Sentry. This isn't your typical Senior Software Engineer position. As a key member of our growing JavaScript SDK team, you'll be at the forefront of innovation, working on everything from our cutting-edge SDKs for Node.js, Bun, Deno, Cloudflare Workers, and other modern server runtimes. You won't just be maintaining code; you'll be pushing the boundaries of what's possible in developer tooling across the rapidly evolving server-side JavaScript landscape. In this role you will Join our JavaScript SDK team and get ready to build the future. You'll be at the forefront, working on: A Universe of JavaScript Challenges: Dive deep into our extensive suite of JavaScript SDKs, with a sharp focus on server-side and edge runtimes — from the battle-tested Node.js ecosystem to cutting-edge alternatives like Bun and Deno, and distributed edge environments like Cloudflare Workers. Your work will directly empower millions of developers to build better, more reliable software, no matter which runtime powers their stack End-to-End Ownership: We believe in giving our engineers the autonomy to see their vision through. You'll have the freedom to plan, implement, and ship your code, from writing

About Sentry Software runs the world and the pace is faster than ever. Sentry helps developers fix errors and performance issues before users notice, so teams can spend less time firefighting and more time building. Trusted by 200,000+ organizations, Sentry is today’s application monitoring standard and our team is building its AI-native future. About the team The Billing team sits at the intersection of product, finance, and infrastructure. They're responsible for ensuring every observable event—errors, logs, traces, tokens—gets accurately measured, priced, and billed. Their work directly impacts company revenue and customer trust, requiring distributed systems expertise, attention to financial accuracy, and deep understanding of product usage patterns. The team works cross-functionally with product, engineering, BizOps, marketing, and sales to build systems that enable new products and pricing models. About the role As a Senior Software Engineer, you will architect and scale the core systems that power Sentry's billing infrastructure, ensuring accuracy and reliability at massive scale. You will collaborate on building the next generation of Sentry’s usage tracking pipeline, processing hundreds of billions of events daily with low latency and financial-grade accuracy. You will help design flexible pricing primitives that support everything from per-event usage billing to complex enterprise contracts, enabling product and sales teams to experiment rapidly while maintaining revenue accuracy and reduced time-to-market for new products. You will contribute to technical decisions on data consistency challenges unique to billing—like handling event delays, retroactive pricing changes, and distributed count reconciliation across our infrastructure. You'll love this job if you Want to solve the "easy to explain, hard to build" problems—like ensuring a customer's bill matches their usage perfectly, even when processing hundreds of billions of events daily across distributed

Who We Are At Justworks, you’ll enjoy a welcoming and casual environment, great benefits, wellness program offerings, company retreats, and the ability to interact with and learn from leaders in the startup community. We work hard and care about our most prized asset - our people. We’re helping businesses get off the ground by enabling them to focus on running their business. We solve HR issues. We’re data-driven and never stop iterating. If you’d like to work in a supportive, entrepreneurial environment, are interested in building something meaningful and having fun while doing it, we’d love to hear from you. We're united by shared goals and shared motivations at Justworks. These are best summed up in our company values, which are reflected in our product and in our team. Our Values If this sounds like you, you’ll fit right in. Who You Are You are self-driven and like to work with others to remove roadblocks. You are curious and love to explore and learn new technologies. You have demonstrated the ability to build, deploy, and maintain large-scale, complex applications. You care more about solutions and impacting the customer experience than using a particular tool or framework. About the role: You will join a small, highly autonomous cross-functional team to build AI agents that fundamentally transform how operations work at scale. Instead of writing bespoke software for every workflow, we are developing an agent platform that can read operational knowledge, reason about it in context, and execute tasks end-to-end. This approach allows us to scale complexity through knowledge and reasoning, rather than simply through code. This is an opportunity to join a foundational team, which currently consists of fewer than five engineers. The work spans critical areas including LLM-powered agent design, robust backend service architecture, tool and integration development, and sophisticated knowledge infrastructure. We are seeking a Senior Software Engineer with a strong pas

Secure Every Identity, from AI to Human Identity is the key to unlocking the potential of AI. Okta secures AI by building the trusted, neutral infrastructure that enables organizations to safely embrace this new era. This work requires a relentless drive to solve complex challenges with real-world stakes. We are looking for builders and owners who operate with speed and urgency and execute with excellence. This is an opportunity to do career-defining work. We're all in on this mission. If you are too, let's talk. Role Overview We are seeking a Senior Software Engineer to build and evolve Okta’s web platform using React and Next.js. In this role, you will bring deep frontend expertise to solve complex engineering problems autonomously from designing scalable page systems and optimizing performance to integrating CMS APIs and refining developer workflows. You work independently on ambiguous problems but thrive in collaboration with designers, content architects, and fellow engineers. AI-assisted development tools are part of how this team works, and you leverage them fluently to move faster while maintaining high standards. This is a hands-on IC role with significant autonomy and real ownership, ideal for an engineer who combines deep technical understanding with strong collaborative instincts. Key Responsibilities Frontend Development & Architecture: Build and maintain reusable page templates, features, and component systems in Next.js using TypeScript and React. Design scalable data-fetching patterns from headless CMS APIs (GraphQL and REST), transforming structured content into polished frontend experiences. Collaborate on content model design with content architects, ensuring CMS data maps cleanly to frontend templates. Implement responsive, accessible, high-performance UI following established design system patterns and propose improvements when existing patterns fall short. Design System Collaboration: Work closely with the design system team to assemble pag

Secure Every Identity, from AI to Human Identity is the key to unlocking the potential of AI. Okta secures AI by building the trusted, neutral infrastructure that enables organizations to safely embrace this new era. This work requires a relentless drive to solve complex challenges with real-world stakes. We are looking for builders and owners who operate with speed and urgency and execute with excellence. This is an opportunity to do career-defining work. We're all in on this mission. If you are too, let's talk. At Okta, we’re building the next generation of authentication for the Agentic AI era. We’re looking for a Senior Engineer to join our AI Authentication team – a group of product-minded, deeply technical engineers delivering features to define what identity and access mean in a world increasingly powered by artificial intelligence. This is a great opportunity for an Senior engineer who thrives in collaborative environments, is eager to grow their technical depth, and wants to build scalable systems that solve real-world security problems. Auth0 Emerging Tech is the Engineering organization where we take care of the hottest technology out there: we ship fast, we don't break things. We are a dynamic and collaborative distributed and diverse team. We value ownership, learning and innovation. We launched our Auth for GenAI offering and we are looking for an Senior Engineer to join us to lead the team taking care of the Identity Protocols parts of the game. Auth0 works with NodeJS ( Javascript or Typescript), a hint of Go and MongoDB or PostgreSQL databases. What will you do: Bring expertise in identity and security while building innovative features and standards that will secure the Agentic AI world Build and maintain scalable services using TypeScript, NodeJS PostgreSQL/MongoDB. Collaborate with other product managers, designers, and senior engineers to deliver features that improve identity and access for GenA