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Fastapi Developer Jobs in Ontario (NOW HIRING)

Python (FastAPI) and/or Node.js * Proven experience building REST APIs, microservices, and ... Prompt engineering and context engineering * Model Context Protocol (MCP) or agent interoperability ...

Senior Full-Stack Engineer, AI Platform The Opportunity Chubb's AI Platform team is building an ... Integrate frontend applications with NestJS and FastAPI backends via REST APIs, Server-Sent Events ...

... , DevOps, and Clinical domain experts to deliver compliant, scalable software that supports ... Design and develop full-stack features using Python/FastAPI or Django (backend) and React ...

... , DevOps, and Clinical domain experts to deliver compliant, scalable software that supports ... Design and develop full-stack features using Python/FastAPI or Django (backend) and React ...

... FastAPI RAG orchestration service integrating Azure AI Search and Azure OpenAI; and a Python ... You are the primary engineer on the NestJS middleware layer and a meaningful contributor to the ...

Developer, AI Transformation Team

Toronto, ON · On-site +1

CA$135K - CA$155K/yr

Strong proficiency in Python and experience with frameworks such as Django, Flask, or FastAPI ... Understanding of asynchronous programming, performance optimization, and scalable backend ...

Backend Engineer III

Toronto, ON · On-site

CA$125K/yr

Experience with FastAPI, SQLAlchemy, and Alembic * Experience with multi-tenant systems or complex data models * Experience building workflow engines, pipelines, or DAG-based processing * Familiarity ...

Experience with FastAPI, SQLAlchemy, and Alembic * Experience with multi-tenant systems or complex data models * Experience building workflow engines, pipelines, or DAG-based processing * Familiarity ...

AI Developer

Oakville, ON · Hybrid

CA$121K - CA$151K/yr

You'll work closely with senior engineers to take AI agents from prototype to secure, production ... Familiarity with FastAPI, Express, or similar web frameworks, and cloud platforms (AWS, Azure)

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Fastapi Developer information

What are some common challenges FastAPI developers face when integrating third-party services or APIs?

FastAPI Developers often encounter challenges when integrating third-party services, such as handling authentication protocols (like OAuth2), ensuring compatibility between JSON schemas, and managing asynchronous calls to avoid performance bottlenecks. It’s also common to troubleshoot and adapt to inconsistencies in external API documentation or rate limits. Collaborating closely with frontend teams and DevOps professionals helps streamline these integrations, ensuring robust, scalable API solutions.

What is the difference between Fastapi Developer vs Backend Developer?

AspectFastapi DeveloperBackend Developer
Required SkillsPython, Fastapi, REST APIs, async programmingMultiple languages (Python, Java, Node.js), REST/SOAP APIs, databases
Work EnvironmentWeb development, API-focused projects, microservicesBroader software development, server-side logic, database management
Industry UsageTech startups, SaaS, API-driven servicesEnterprise, e-commerce, finance, various industries

Fastapi Developers specialize in building high-performance APIs using Python and Fastapi, often within microservices architectures. Backend Developers have a broader scope, working with multiple languages and technologies to develop server-side applications across various industries. While Fastapi Developers focus on API efficiency, Backend Developers handle comprehensive backend systems.

What are the key skills and qualifications needed to thrive as a FastAPI developer?

To thrive as a FastAPI Developer, you need strong proficiency in Python programming, RESTful API design, and experience with FastAPI, often supported by a background in computer science or related fields. Familiarity with tools like SQL/NoSQL databases, Docker, and cloud platforms, as well as knowledge of asynchronous programming and API documentation tools like Swagger, is typically required. Excellent problem-solving skills, attention to detail, and effective communication set outstanding FastAPI developers apart. These skills are crucial for building reliable, high-performance APIs that meet modern application demands and facilitate seamless team collaboration.

What is a FastAPI developer?

A FastAPI Developer is a software engineer who specializes in building web applications and APIs using the FastAPI framework, which is a modern, fast (high-performance) web framework for Python. FastAPI Developers are responsible for designing, developing, and maintaining backend services and APIs that are efficient, robust, and scalable. They often work with databases, authentication, and deployment processes, and ensure that the API endpoints adhere to best practices for security and performance. Their work is crucial for enabling smooth communication between front-end applications and backend systems.

What are popular job titles related to Fastapi Developer jobs in Ontario?

For Fastapi Developer jobs in Ontario, the most frequently searched job titles are:

What job categories do people searching Fastapi Developer jobs in Ontario look for?

The top searched job categories for Fastapi Developer jobs in Ontario are:

Infographic showing various Fastapi Developer job openings in Ontario as of August 2026, with employment types broken down into 72% Full Time, 14% Part Time, and 14% Contract. Highlights an 80% Physical, 6% Hybrid, and 14% Remote job distribution.

Full Stack Developer

Quantiphi, Inc.

Toronto, ON • Remote

Full-time

Re-posted 4 days ago


Job description

While technology is the heart of our business, a global and diverse culture is the heart of our success. We love our people and we take pride in catering them to a culture built on transparency, diversity, integrity, learning and growth.
If working in an environment that encourages you to innovate and excel, not just in professional but personal life, interests you- you would enjoy your career with Quantiphi!

About Quantiphi:

Quantiphi is an award-winning, AI-First digital engineering and consulting company focused on delivering high-impact Services and Solutions that help organizations solve what truly matters. We partner with enterprises to reimagine their businesses through intelligent, scalable, and transformative AI driving measurable outcomes at the very core of their operations.

Since our founding in 2013, Quantiphi has tackled some of the world's most complex business challenges by combining deep industry expertise, disciplined cloud and data engineering practices, and cutting-edge applied AI research. Our work is rooted in delivering accelerated, quantifiable business value, not just technology for technology's sake.

Headquartered in Boston, Quantiphi is a global organization with 4,000+ professionals serving clients across key industry verticals, including BFSI, Healthcare & Life Sciences, CPG, MFG, TME etc. As an Elite and Premier partner to leading cloud and AI platforms such as NVIDIA, Google Cloud, AWS, and Snowflake, we build and deliver enterprise-grade AI services and solutions that create real-world impact.

We've been recognized with:

  • 17x Google Cloud Partner of the Year awards in the last 8 years.

  • 3x AWS AI/ML award wins.

  • 3x NVIDIA Partner of the Year titles.

  • 2x Snowflake Partner of the Year awards.

  • We have also garnered top analyst recognitions from Gartner, ISG, and Everest Group.

  • We offer first-in-class industry solutions across Healthcare, Financial Services, Consumer Goods, Manufacturing, and more, powered by cutting-edge Generative AI and Agentic AI accelerators.

  • We have been certified as a Great Place to Work for the third year in a row- 2021, 2022, 2023.

Be part of a trailblazing team that's shaping the future of AI, ML, and cloud innovation.

Your next big opportunity starts here!

For more details, visit: Website or LinkedIn Page.

Role: Full Stack Software Developer

Experience Level: 5-10 yrs

Work Location: US East/Canada (Remote)

Role Overview:

We're looking for a Full Stack Software Developer to design and build scalable, high-performance applications powering next-generation Agentic AI platforms.

In this role, you'll lead the development of API-first, distributed systems and contribute across the stack from backend microservices to modern frontend experiences. You'll partner closely with AI/ML teams to integrate LLM-driven workflows, RAG architectures, and multi-agent systems into production-grade applications.

This is a hands-on engineering role with strong ownership across architecture, developer experience, and system reliability.

Key Responsibilities:

  • Design and build scalable full stack applications using React, TypeScript, and Next.js on the frontend and Python (FastAPI) and/or Node.js on the backend

  • Architect and maintain RESTful APIs and microservices with strong versioning, backward compatibility, and API-first design principles

  • Develop distributed systems leveraging event-driven architectures, messaging systems (Kafka, Pub/Sub), and asynchronous processing

  • Build and integrate LLM-powered applications, including RAG pipelines, agentic workflows, and tool-calling frameworks (LangChain, LangGraph)

  • Collaborate with AI/ML teams to integrate model serving platforms and orchestrate multi-agent systems

  • Implement real-time capabilities using WebSockets, Server-Sent Events (SSE), or streaming frameworks

  • Ensure high-quality engineering standards across testing (TDD/BDD), CI/CD pipelines, and infrastructure-as-code

  • Deploy and manage cloud-native applications on GCP and/or Azure, leveraging Docker and Kubernetes

  • Champion observability and monitoring using logging, metrics, and tracing (e.g., OpenTelemetry)

  • Build developer-friendly tools including SDKs, documentation, and API portals

  • Mentor engineers and contribute to system design, architecture reviews, and best practices

Basic Qualifications:

  • 5-10 years of experience in full stack software development

  • Strong expertise in:

  • Frontend: React, TypeScript, Next.js

  • Backend: Python (FastAPI) and/or Node.js

  • Proven experience building REST APIs, microservices, and distributed systems

  • Hands-on experience with PostgreSQL and data modeling

  • Experience with Docker, Kubernetes, and cloud platforms (GCP and/or Azure)

  • Strong knowledge of CI/CD pipelines (GitHub Actions or similar)

  • Experience with API lifecycle management (authentication, versioning, rate limiting)

  • Solid understanding of system design, scalability, and performance optimization

  • Experience integrating or building applications with LLMs, RAG, or Agentic AI systems

  • Familiarity with LangChain, LangGraph, or similar frameworks

Other Qualifications (OQs):

  • Experience with:

    • LlamaIndex, advanced LangGraph workflows, or multi-agent orchestration

    • Prompt engineering and context engineering

    • Model Context Protocol (MCP) or agent interoperability frameworks

  • Exposure to GraphQL, gRPC, and advanced API design patterns

  • Experience with event-driven systems (Kafka, Pub/Sub, Redis)

  • Knowledge of vector databases (pgvector, Pinecone, Milvus)

  • Experience building real-time/streaming UIs (WebSockets, SSE)

  • Understanding of OAuth 2.0, OIDC, RBAC for secure systems

  • Strong testing practices (TDD, Playwright, contract testing)

  • Experience with OpenTelemetry or similar observability tooling

  • Familiarity with Domain-Driven Design (DDD) and API-first architecture

Healthcare Domain Experience (Nice to Have):

  • Experience working with FHIR R4, HL7 v2, or SMART on FHIR

  • Integration with EHR systems (e.g., Epic)

  • Understanding of HIPAA compliance and healthcare data privacy

  • Exposure to clinical workflows, CDS Hooks, or patient-facing applications

  • Experience building clinical decision support systems or healthcare interoperability solutions

What's in it for YOU at Quantiphi:

  • Make an impact at one of the world's fastest-growing AI-first digital engineering companies.

  • Upskill and discover your potential as you solve complex challenges in cutting-edge areas of technology alongside passionate, talented colleagues.

  • Work where innovation happens - work with disruptive innovators in a research-focused organization with 60+ patents filed across various disciplines.

  • Stay ahead of the curve immerse yourself in breakthrough AI, ML, data, and cloud technologies and gain exposure working with Fortune 500 companies.

If you like wild growth and working with happy, enthusiastic over-achievers, you'll enjoy your career with us!