Senior Software Developer - Tax

Doist; Toronto; On-site; CAD 110,000 - 150,000; Full time

Benefits offered by this job

Health benefits

Vacation days (20 days)

Unlimited sick/mental health days

Work outside Canada up to 90 days/year

Job summary

Wealthsimple in Toronto is seeking a Senior Software Developer for the Tax team. You will own end-to-end engineering, build full-stack experiences with React and Python, and help modernize legacy frontend code.

You’ll shape technical direction, mentor teammates, and contribute to production systems in a regulated environment. You’ll collaborate across Product, Design, Operations, and Compliance to deliver practical solutions, with an emphasis on API design, testing, observability, and security,

Qualifications

• Significant professional software engineering experience.
• Strong full-stack development experience (React/modern frontend).
• Professional Python experience or quick productivity in Python-based systems.
• Experience leading complex technical projects and breaking problems into steps.
• Mentoring engineers and improving team effectiveness.
• Strong API design, testing, debugging, monitoring, and operational excellence.
• Ability to collaborate with technical and non-technical partners in regulated environments.
• Clear written and verbal communication; low-ego feedback mindset.
• Experience with AI-first development workflows (Claude) in production.

Responsibilities

• Own complex, end-to-end engineering projects from design to delivery and improvement.
• Build and maintain full-stack experiences using React on the frontend and Python on the backend.
• Contribute to and modernize legacy frontend codebases (e.g., jQuery/Backbone).
• Design and operate reliable services and integrations for tax filing and reporting workflows.
• Collaborate with Product, Design, Operations, Compliance, and engineering teams to surface trade-offs and deliver practical solutions.
• Make architectural, testing, observability, security, and maintainability decisions.
• Participate in hiring and interviewing processes; mentor teammates and raise engineering standards.

Skills

Full-stack development

Python

Mentoring

API design

Automated testing

Debugging

Monitoring

Collaboration

AI workflows (Claude)

Job description

Build something people loveWealthsimple is Canada's leading financial innovator. The company offers a full suite of simple, sophisticated financial products across managed investing, do-it-yourself trading, cryptocurrency, tax filing, spending and saving. Wealthsimple currently serves more than 4 million Canadians and holds over $155 billion in assets under administration. The company was founded in 2014 by a team of financial experts and technology entrepreneurs, and is headquartered in Toronto, Canada.

We're proud of what we've built - and we're just getting started. Read our Culture Manual and learn more about how we work.

About the role

As a Senior Software Developer on the Tax team, you will work across the stack to build, improve, and operate products that help Canadians complete their tax obligations with confidence. You will take meaningful projects from discovery and technical design through implementation, launch, and iteration. You'll help shape technical direction, raise engineering standards, and mentor teammates while contributing directly to production code. This role is a strong fit for someone who enjoys complex, regulated domains; can work comfortably across frontend and backend systems; and brings sound judgment to ambiguous problems.

What you’ll do

• Own complex, end-to-end engineering projects, from problem definition and technical design through delivery and ongoing improvement.
• Build and maintain full-stack experiences using React on the frontend and Python on the backend.
• Contribute to existing frontend code, including legacy jQuery and Backbone components, while helping the team modernize and simplify the codebase over time.
• Design and operate reliable services and integrations that support tax filing, reporting, and other critical client workflows.
• Partner with Product, Design, Operations, Compliance, and other engineering teams to clarify requirements, surface trade-offs, and deliver practical solutions.
• Make thoughtful decisions about architecture, testing, observability, security, and maintainability.
• Use AI-native development workflows to improve the speed and quality of design, implementation, debugging, and programming.
• Raise the technical bar through design reviews, code reviews, documentation, pairing, and mentorship.
• Participate in the team’s hiring and interview process.
• Help create a culture of clear communication, learning, and shared ownership.

What you bring

• Significant professional software engineering experience, with a track record of shipping and operating production systems.
• Strong full-stack development experience, including React or a comparable modern frontend framework.
• Professional experience with Python, or demonstrated ability to become productive quickly in Python-based systems.
• Experience leading complex technical projects and breaking ambiguous problems into clear, deliverable steps.
• A history of mentoring engineers and improving the effectiveness of the people around you.
• Strong engineering fundamentals, including API design, automated testing, debugging, monitoring, and operational excellence.
• The ability to collaborate effectively with technical and non-technical partners in a regulated or high-trust environment.
• Clear written and verbal communication, sound judgment, and a low-ego approach to feedback and teamwork.
• An AI-first development workflow that uses tools such as Claude thoughtfully while maintaining engineering rigor and accountability for the final result.

Helpful experience

• Experience in fintech, tax, accounting, payments, or another regulated financial-services domain.
• Familiarity with Canada Revenue Agency processes, tax reporting, or tax-filing products.
• Experience with accounting platforms such as QuickBooks.
• Experience modernizing or migrating legacy frontend codebases.
• Experience working in a fast-moving product engineering environment with broad individual ownership.

Why Wealthsimple?

• Top-tier health benefits and life insurance
• Long-term group savings with employer match, through Wealthsimple for Business
• 20 vacation days, 4 wellness days, and unlimited sick and mental health days per year
• 90 days away: work outside Canada for up to 90 days per year
• Employee resource groups, including Rainbow (2SLGBTQ), Women of WS, and Black at WS

ICYMITechnology & Innovation at Wealthsimple:

We move quickly and build thoughtfully. That means we're always looking for better ways to work - whether that's new tools, AI, or rethinking how we approach a problem. We don't expect you to have all the answers, but we do expect curiosity and a willingness to evolve alongside the products we're building.

Inclusion Statement: We're building products for a diverse world, and we need a diverse team to do it well. We strongly encourage applications from everyone, regardless of race, religion, colour, national origin, gender, sexual orientation, age, marital status, or disability status.

Accessibility Statement: We're committed to an accessible hiring experience. If you need any accommodations throughout the interview process, please let us know - We'll work with you to make sure you have what you need. We also welcome any feedback on how we can better accommodate candidates with accessibility needs.

AI in Hiring: We may use artificial intelligence (AI) tools to support parts of our hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our team but don't replace human judgment - all final hiring decisions are made by people.