Senior Python Developer

Fulfil is hiring a Senior Python Engineer in Toronto to help build the core operating system for modern commerce brands.

This is not traditional ERP maintenance. Fulfil powers fast-moving DTC brands across orders, inventory, fulfillment, shipping, payments, finance, and 200+ third-party systems. You’ll work on the core product, focusing on native integrations, complex data flows, production debugging, and high-quality Python engineering.

This role is for someone who wants broad ownership in a lean team and has strong opinions on what good Python looks like.

Location: Toronto, ON (in-office during onboarding; hybrid 3 days/week in office after)

Type: Full-Time

Expected Start Date: Immediately

What You’ll Do

Own the Full Stack

• Design, build, and maintain end-to-end functionality across our Python-based platform, from backend services to frontend integrations.
• Work within a large, mature codebase while contributing to its long-term evolution and scalability.
• Debug complex production issues across APIs, data flows, two-way sync, orders, inventory, and fulfillment workflows.

Deliver Features at Speed

• Lead the design, development, testing, and deployment of new features that directly support high-growth merchants.
• Balance rapid delivery with long-term maintainability.

Apply AI in Production

• Use AI thoughtfully as an engineering multiplier while maintaining ownership of code quality, design decisions, and production reliability.
• Integrate AI-powered capabilities into Fulfil’s ERP using LLMs (e.g., OpenAI, Anthropic).
• Build intelligent workflows that enhance automation, decision‑making, and merchant experience across orders, financials, and operations.

Scale with Confidence

• Design and optimize REST and GraphQL APIs (600+ endpoints), microservices, and background processing pipelines.
• Work with containerized infrastructure (Docker/Kubernetes) to support high availability and zero‑downtime deployments.

Champion Code Quality

• Refactor and modernize legacy systems.
• Write well‑tested, readable code using pytest.
• Review Python code with strong judgment – ensuring it is readable, maintainable, scalable, and aligned with the product’s direction.

Build Ecosystem Integrations

• Develop and maintain integrations with major commerce platforms (Shopify, Amazon) and logistics providers (FedEx, DHL).
• Ensure reliable data flows across external systems and Fulfil’s core platform.

What You Bring

• 5+ years of experience, ideally, building applications at scale from scratch.
• Strong production Python experience building and maintaining real applications; scripting or automation alone is not enough.
• Hands‑on experience with ORMs (e.g., SQLAlchemy, Django ORM) and relational databases (PostgreSQL preferred).
• Proficiency with distributed systems components such as Celery, Redis, RabbitMQ, and background processing.
• Experience writing automated tests (pytest) and using Git in a collaborative environment.
• Demonstrated ownership – seeing projects through from design to production and ongoing support.

You’ll Thrive Here If

• You like small teams where engineers own broad, meaningful problems.
• You enjoy reading, debugging, and improving mature codebases.
• You care about Python quality, not just whether the code works.
• You want to build software that sits at the center of how modern commerce brands operate.

This is Not the Right Fit If

• Your Python experience is mostly scripting, automation, or side projects.
• You prefer architecture‑only roles and do not want to stay hands‑on.
• You want a narrow role where you own one small part of the system.
• You need a highly layered product organization where every requirement is fully defined before engineering starts.
• You are looking for fully remote work.

Our Approach to AI

What We Do

• Leverage LLMs (OpenAI API, Claude API) to embed AI‑driven capabilities into Fulfil’s ERP, powering natural language interfaces, intelligent automation, and merchant‑facing insights (e.g., Fulfil x MCP integrations with Claude).
• Focus on applied AI for commerce operations – integrating models to solve real problems like order management, financial analysis, customer insights, and logistics optimization.

What We Don’t

• We are not a core ML/AI research company – we don’t train or fine‑tune foundation models.
• We focus on integrating and productizing AI, rather than building new ML frameworks or developing custom model architectures.

Bonus Points

• Experience scaling systems at a high‑growth tech company.
• Familiarity with cloud platforms (Google Cloud, Heroku, etc.).
• Passion for optimizing distributed systems or e‑commerce workflows.
• Domain‑Focused Product Engineering: Experience building or scaling production software in commerce, logistics, or operations domains (e.g., order management, inventory, fulfillment, WMS) or in FinTech/financial systems (payments, reconciliation, revenue recognition, invoicing).

Why Join Fulfil

• Build systems that power real‑world commerce at a global scale.
• Work with a highly skilled, collaborative, and distributed engineering team.
• Competitive compensation, benefits, and growth opportunities aligned with Canadian market standards.

About Fulfil

Fulfil is the modern ERP for commerce. Built to power the fastest‑growing eCommerce brands, our platform brings together order management, inventory, accounting, and more, turning complex operations into a strategic advantage.

We’re trusted by brands like HexClad, Ridge Wallet, Caraway, and Resident, and backed by people who want to change the way merchant operations are run. We believe in deep work, radical accountability, and building tools that let sharp people move faster.

WWhat It’s Really Like to Work Here

• Founder‑led, bootstrapped, and profitable – Fulfil is product‑obsessed and built for long‑term impact, not short‑term hype.
• We move quickly because our customers depend on us – Our customers run real operations across orders, inventory, fulfillment, warehouses, accounting, and customer promises.
• High ownership, low bureaucracy – You will not be handed tickets that fully describe the solution, and you will not wait weeks for approvals.
• You are expected to think through the problem – You will seek context, talk to the right people, exercise good judgment, make recommendations, and own the outcome.
• Clean code matters – We care deeply about readable, maintainable code that teammates can understand, support, and build on later.
• Reviews are rigorous – Pull requests may go through multiple rounds of review. We would rather delay a release than ship code that creates future operational pain.

You will thrive here if you want:

• Autonomy, direct customer context, strong engineering standards, and the chance to help build the ERP platform behind the next generation of commerce brands.

This is not the right fit if you want:

• A highly layered organization, a narrow coding‑only role, or a roadmap where every decision has already been made for you.

#J-18808-Ljbffr