Full Stack Engineer

Hammer Search Partners LLC; Montreal (administrative region); On-site; CAD 80,000 - 120,000; Full time

Benefits offered by this job

Comprehensive health, dental, and vision

Flexible PTO

Remote friendly culture

Growth path opportunities

Job summary

Oo Daris in Montreal is seeking an experienced developer to build intuitive product surfaces and APIs that enhance user experience and trust in AI systems. You will work on creating a live agent run console and ensure contracts are well-defined to prevent operational drift.

The ideal candidate has expertise in React, TypeScript, and accessibility design, along with a strong understanding of performance metrics. Join us to lead the development of cutting-edge multi-agent intelligence systems.

The role offers comprehensive benefits, flexible PTO, and opportunities for growth within the company.

Qualifications

• Deep understanding of web performance and typed APIs.
• Experience with building data dense UIs and accessibility.
• Proficient in managing microservices architecture.

Responsibilities

• Build product surfaces that are intuitive and explanatory.
• Develop a live agent run console with performance tracking.
• Create and maintain a typed FastAPI BFF for frontend applications.

Skills

React 18

TypeScript

API development

Accessibility design

Docker

Git based CI/CD

Education

BS or MS in Computer Science

Tools

FastAPI

OpenAPI

JSON Schema

Job description

Overview

The Mission Agentic AI only matters if customers can see it, steer it, and trust it. You will build the surfaces, APIs, and developer experience that let retail teams configure agents, approve recommendations, and quantify ROI without filing a ticket. Your work turns complex multi agent decisions into clear, fast, explainable product experiences.

What You Will Own

• Product surfaces that explain themselves.
• Live agent run console with streamed tokens and tool events, approvals and guardrails UX, connector setup, evaluation reports, and parity dashboards that make drift visible and fixable.
• Real time that feels instant. SSE token streams, tool timelines, and collaborative approvals with optimistic UI and backpressure controls that hold up under load.
• Contracts that hold the line. Typed APIs using OpenAPI and JSON Schema, generated clients, OAuth2 or API keys or SSO, RBAC, rate limits, and full audit trails with no drift between UI, BFF, and services.
• Design system and accessibility. Compose data dense, legible UIs (virtualized grids, timelines, trace viewers) in React 18 + TypeScript + Tailwind + shadcn patterns that still feel lightweight.
• Quality as a feature. Performance budgets, bundle guardrails, Vitest and Playwright coverage, canary and feature flag rollouts, instant rollback paths.
• BFF done right. Maintain a typed FastAPI BFF that presents a stable surface to the UI and shields microservice complexity.
• Canonical data models. Keep UI, BFF, and services aligned, preventing breaking changes and making analytics first class.

Impact You Will Drive

1. 30 days: Launch streamed agent run console with tool traces and RBAC aware approvals, with structured logs, traces, and baseline Web Vitals captured.
2. 60 days: Deliver connector flows with resilient retries and strict schema validation, achieving p95 Time to Interactive under 2 seconds on key screens and establishing error budgets.
3. 90 days: Ship a public TypeScript SDK and docs generated from OpenAPI, add E2E coverage on critical paths, and enable zero downtime deploys with progressive rollouts and quick reverts.

Environment

You do not need all of this on day one, but you will touch:

• Frontend: React 18, TypeScript (strict), Tailwind, shadcn patterns, React Hook Form with Zod, Zustand or MobX slices, TanStack Query, Vitest, Playwright, product analytics.
• APIs and BFF: Typed FastAPI BFF in front of domain microservices, OpenAPI + JSON Schema contracts, deterministic client generation.
• Platform and infra: Docker, Git based CI/CD, Infrastructure as Code, managed container platforms, modern frontend hosting.
• Architecture: Containerized microservices, typed contracts, canonical data models, streaming UX.

Education and Fundamentals

Preferred: BS or MS in Computer Science, Software Engineering, HCI, or related field. Not required: Equivalent experience is welcome—show mastery of web performance, typed APIs, accessibility, and production reliability through shipped systems or portfolio work.

What Great Looks Like

• Own performance and reliability from day zero with failure modes, retries, and backpressure designed in.
• Accessibility by default—keyboard navigation, focus order, reduced motion, thoughtful empty/loading/error states.
• Contract discipline that prevents drift and enables painless handoffs across teams.
• Product empathy that makes explainability and ROI visible in the UI, not buried in logs.

Nice to Have

• Superpowers: Deep experience with design systems or accessibility (WCAG, ARIA).
• Data dense UI patterns such as virtualized grids, timelines, or trace viewers.
• Prior work on LLM product UIs (streaming, deterministic function calling, evaluation dashboards).
• Server driven UI experience.

Why This Role Matters

You will build the front door to multi agent intelligence and define how retail teams trust and govern AI. Modern, pragmatic stack—contracts, BFF, microservices, and tooling that deliver speed without sacrificing correctness. High trust and high ownership with real accountability.

How We Work

Golden Workflow: Plan → Contracts → Code → Tests → Docs → Rollout. Typed inputs and outputs everywhere—parity stays green before merge. Quality gates: lint + types clean, ≥90% coverage on changed files, happy path E2E, observability in place before release. Security: least privilege IAM, secrets hygiene, structured audit logs. Small, senior, calm team. Pragmatic research. What beats the baseline wins.

The Upside

Comprehensive health, dental, and vision plus life, disability, and EAP or telemedicine. Flexible PTO and remote friendly culture with Montréal HQ community days. Growth path from owning a surface to owning a product area to leading across UI, BFF, and platform—growth follows impact.

Hiring Process

1. 25 minute intro for mutual fit.
2. Deep dive in UI architecture, BFF, or performance.
3. Practical working session with realistic design and problem solving.
4. Team loop with product and engineering.
5. Founder conversation for scope and offer.

Ready to Apply?

Apply if you are ready to craft the front door of retail’s Agentic OS. Use the application form on this page or email your profile to [e-mail] with the role title in the subject line.