Jobless Developer
APPLY logo
APPLY

Posted 3 months ago

Open

Principal Agentic Engineer (Back-end)

TorontoHybridFull-time

AI Summary

Senior backend leader responsible for designing, building, and scaling AI-powered backend systems, with architectural oversight, client-facing collaboration, and mentorship of engineers.

About this role

ABOUT APPLY DIGITAL
Apply Digital is a global AI-native transformation partner, client-obsessed and built for a new era of client services. We bring together industry expertise and elite talent to connect strategy, agentic experiences, technology, and data for the world's most ambitious organizations.

With the agility to move fast and the experience to deliver with precision, Apply Digital works with clients like Arc'teryx, Lululemon, and Kraft Heinz.

For more information, visit applydigital.com
LOCATION: Apply Digital is hybrid/remote friendly. The preferred candidate should be based in Canada, working in hours that align to ET (Eastern Timezone) or PT (Pacific Timezone).
THE ROLE:

The Principal Agentic Engineer (Back-end) is a senior technical leader within our engineering organization, responsible for designing, building, and scaling robust backend systems that support modern, AI-powered digital products. This role combines deep backend engineering expertise with strong architectural judgment, AI-system fluency, and client-facing leadership.
As a Principal Agentic Engineer, you will lead technical direction across complex backend systems, mentor engineers, and partner closely with clients and internal teams to deliver production-grade solutions. You will play a critical role in designing distributed, cloud-native architectures and integrating large language models (LLMs), vector databases, and AI agents into real-world applications. You will engineer teams of coding agents to accomplish implementation requirements for the systems you will be building.
You bring proven leadership at a Staff or Lead level, with a track record of delivering complex software initiatives end-to-end. You operate with high autonomy and can take loosely defined goals and turn them into well-architected, shipped software.

RESPONSIBILITIES

  • Lead the design and development of scalable, secure, and high-performance backend systems using Python and modern cloud-native patterns.
  • Apply spec-driven development practices to ensure clarity, quality, and predictable delivery.
  • Organizing, distributing and translating backlog requirements from Product, UX and other disciplines, into detailed spec driven requirements for Agents to implement.
  • Coordinate teams of coding agents to deliver engineering requirements.
  • Design and implement RESTful APIs to support frontend, mobile, and third-party integrations.
  • Architect and deliver AI-powered backend solutions, including: Vector stores and Retrieval-Augmented Generation (RAG) pipelines, integration with LLMs (e.g., Gemini, Claude, GPT-4/5), and use of AI coding agents and developer copilots to improve delivery velocity.
  • Develop and maintain systems using Google Cloud Platform (GCP), with hands-on experience in, Vertex AI, Google Gen AI APIs.
  • Leverage Agent Development Kits (ADKs) (e.g., Google ADK) to design and implement intelligent agent-based systems.
  • Ensure systems are observable, reliable, and debuggable in production environments.
  • Collaborate with engineers to design well-architected, maintainable solutions aligned with business goals.
  • Mentor and guide engineers, fostering technical excellence and continuous learning.
  • Partner with Project Managers and cross-functional teams to manage delivery risks and timelines.
  • Communicate complex technical concepts clearly to both technical and non-technical stakeholders, including clients.

    • REQUIREMENTS

  • Strong experience with Python 3 for backend development.
  • Experience designing and consuming RESTful APIs.
  • Proven experience with spec-driven development.
  • Hands-on experience using AI coding agents (e.g., Copilot, Claude Code).
  • Strong prompt engineering skills.
  • Experience working with LLMs (e.g., Gemini 3, Claude Opus, GPT-4.x/5.x).
  • Experience implementing vector stores and RAG architectures.
  • Experience with Agent Development Kits (e.g., Google ADK).
  • Strong experience with Google Cloud Platform (GCP).
  • Hands-on experience with Vertex AI and Google Gen AI APIs.
  • Experience with relational and non-relational databases.
  • Experience with Git and CI/CD pipelines.
  • Strong system design fundamentals, including queues, caching strategies, database schema design, and API design. You know how to build systems that survive and scale in production.
  • Experience designing AI agents, agent task planning, and reasoning patterns.
  • Agent observability and debugging experience.
  • Ability to clearly articulate goals, constraints, and context for agentic systems; reason through edge cases and failure modes; and iteratively refine agent behavior based on observed outcomes.
  • Comfort understanding and integrating across the full stack; experience with TypeScript and modern JavaScript is highly beneficial.
  • Excellent English communication skills (written and verbal), with the ability to explain complex technical concepts to both technical and non-technical audiences.
  • Excellent command of the English language to guide coding agents to complete required coding tasks.
  • Experience working effectively with fully remote, distributed teams.
  • Experience working in a consultancy, agency, or professional services firm.
  • Ability to thrive in a flexible, fast-paced delivery environment.

    • NICE TO HAVES

  • Experience with BMAD Method or similar spec driven development frameworks.
  • Familiarity with layered and distributed architectures.
  • Experience with Terraform.
  • Experience with additional backend languages.
  • Experience with gRPC or other communication patterns.
  • Experience with eCommerce platforms or complex integrations.

    • Skills

    Agent Development KitsAgent OrchestrationAI Coding AgentsAPI DesignCI/CDDatabases (relational And Non-relational)GCPGitGoogle Gen AI APIsLLMs IntegrationObservabilityPythonQueues And CachingRAG PipelinesRESTful APIsSpec-Driven DevelopmentSystem DesignTypeScript/JavaScript (beneficial)Vector StoresVertex AI

    Explore related jobs

    More jobs at APPLY

    Similar Agent Development Kits jobs

    Jobs in Toronto

    Browse these categories

    API Design JobsCI/CD JobsGCP JobsGit JobsObservability Jobs