# Senior Software Engineer, Applied AI

**Company:** [Justworks](https://hotfix.jobs/companies/justworks)
**Location:** Toronto, Canada
**Role:** Backend Engineering
**Salary:** CA$188k – CA$242k/yr
**Experience:** 5+ years
**Skills:** Go, Ruby on Rails, JavaScript, Java, C#, Python, Vue, MySQL, Kafka, AWS, Redis, Elasticsearch, Docker, Terraform, Kubernetes
**Posted:** 2026-08-05

> Build and operate backend infrastructure for an AI agent platform, including orchestration, integrations, knowledge systems, trust and safety, and evaluation tooling. The role requires 5+ years of backend experience, hands-on LLM or agent experience, strong API design, and ownership in an ambiguous product environment.

## Job Description

## Responsibilities

- Design, build, and own core components of the agent platform, including the orchestration layer and tool integrations with internal systems.
- Build and evolve the capabilities layer, including APIs, data access patterns, and service integrations for agents to execute operational workflows.
- Architect knowledge and memory infrastructure so agents can retrieve data and act across systems.
- Design and implement trust and safety frameworks, including audit trails, human-in-the-loop controls, and guardrails for safe, auditable AI-driven operations.
- Contribute to agent evaluation and testing infrastructure, defining measures for accuracy, reliability, and behavioral regression.
- Partner with Operations to understand workflows, identify automation opportunities, and translate process knowledge into agent capabilities.
- Mentor engineers as the team grows.

## Requirements

- 5+ years of backend engineering experience building and operating production systems.
- Hands-on experience with large language models and AI agents, including orchestration, retrieval-augmented generation, tool or function calling, or similar technologies.
- Strong API design and systems integration skills.
- Product-minded approach, including contributing to product decisions and questioning requirements.
- Proven ownership of complex projects in ambiguous, early-stage environments.
- Strong backend engineering fundamentals and experience designing, building, and operating production systems.
- Curiosity and motivation to build practical, real-world products using AI and large language models.

## Technologies

- Golang
- Ruby on Rails
- JavaScript
- Java
- C#
- Python
- Vue.js
- MySQL
- Kafka
- AWS
- Git
- Memcache
- Redis
- Elasticsearch
- Docker
- Terraform
- Kubernetes
- CircleCI
- Datadog

## Compensation

- Base wage range: **$188,000.00–$242,000.00 CAD per year** for the Toronto office.

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