Senior Full-Stack Developer – Business Applications & AI

McGill St Laurent; Montreal; On-site; CAD 100,000 - 150,000; Full time

Benefits offered by this job

Group insurance

RRSP

Paid vacation from day one

Transit reimbursement (80%)

Give & Match program

Office with gym and golf simulator

Job summary

McGill St Laurent, a Montreal‑based multi‑entity group, seeks a senior full‑stack developer to own end‑to‑end projects across divisions including CWP Energy, GSL Grain and MSL Climate Solutions. You’ll shape architecture, drive NetSuite customisations, and push Claude‑driven automation, collaborating with traders, operations and finance.

You will lead internal tool design, oversee external developers, and ensure data consistency across dashboards and NetSuite while delivering robust,

Qualifications

• Bachelor’s degree in software engineering, computer science or related field or equivalent experience.
• 5+ years of full‑stack development experience delivering end‑to‑end systems.
• Strong JavaScript and Python, with React frontend experience.
• Experience designing and consuming REST APIs and building system‑to‑system integrations.
• Solid SQL skills: data modeling and query optimization.
• Hands‑on experience applying LLMs to business processes.
• Excellent written and spoken French and English.

Responsibilities

• Design, build, test and deploy internal applications and integrations end to end (e.g., client portal, billing, accounts payable automation).
• Define the architecture of internal tools and system integrations, including NetSuite.
• Set development standards, lead code reviews and drive knowledge sharing.
• Collaborate with external developers and gradually bring their work in‑house.
• Act as technical lead on NetSuite customisations, scripts and workflows across entities.

Skills

JavaScript

Python

React

REST APIs

SQL

LLMs

French/English

Education

Bachelor’s degree in software engineering or related field

Tools

NetSuite

Claude Code

MCP integrations

Job description

MSL is a Montreal-based, multi-entity organization with divisions including CWP Energy (physical power trading), GSL Grain, CWP Wood and MSL Climate Solutions. We are about 170 people and growing fast, and we run on speed, ownership and a strong team culture.

The Role

You’ll be our in‑house senior full‑stack developer and the technical go‑to for development projects across all of our entities. You’ll design and deliver the solutions that keep our operations running, from back‑office automation to simplifying our trading tools, working directly with traders, operations and finance.

You’ll join a team that’s already in motion: our Transformation Lead is driving the overhaul of our processes and tools, and an in‑house developer is already contributing.

We already use Claude every day. We’re looking for someone to take that usage from experimentation to robust solutions: architecture, controls, testing and maintainability.

NetSuite is our ERP across the group, and a large share of your projects will involve it: customisations, integrations and migrating our remaining entities. SuiteScript experience is an asset.

What You’ll Do

Development and architecture

• Design, build, test and deploy internal applications and integrations end to end (e.g., client portal, billing and accounts payable automation)
• Define the architecture of our internal tools and the integrations between our systems, including NetSuite
• Set development standards, lead code reviews and drive knowledge sharing
• Work with our external developers and gradually bring their work in‑house

NetSuite

• Act as technical lead on NetSuite: customisations, scripts and workflows across all of our entities
• Support the technical side of migrating our remaining entities to NetSuite
• Ensure data consistency between our tools, our dashboards and NetSuite

AI and automation

• Take our use of Claude (Claude Code, agents, MCP integrations) from experimentation to documented, tested and controlled solutions
• Identify the finance and operations processes where automation will have the most impact

Working with the business

• Turn the needs of traders, operations and accounting into concrete, reliable solutions
• Scope and prioritise requests based on value, effort and risk, and recommend the right technical approach
• Drive adoption: documentation, training and user support

What You Bring

Requirements

• Bachelor’s degree in software engineering, computer science or a related field, or an equivalent combination of education and experience
• 5+ years of full‑stack development experience, including projects delivered end to end in production
• Strong JavaScript and Python, and front‑end experience with React
• Experience designing and consuming REST APIs and building system‑to‑system integrations
• Solid SQL: data modelling and query optimisation
• Hands‑on experience applying LLMs to business processes
• Excellent written and spoken French and English

Nice to have

• NetSuite experience (SuiteScript, SuiteFlow, SuiteTalk) (strong asset)
• Experience with Claude Code, agents or MCP integrations
• Background in finance, trading or commodities
• Experience as a tech lead or the technical reference for a team

About you

• You have strong business sense: you can understand a finance or operations process end to end before you write code.
• You communicate clearly with non‑technical people, ship in increments with business value in mind, and take testing and documentation seriously.
• You’re autonomous, curious and comfortable in an organisation that’s transforming.

What We Offer

• A stimulating, dynamic and collaborative work environment. Curious to learn more? McGill St Laurent
• The opportunity to be part of an entrepreneurial culture that encourages initiative
• Comprehensive group insurance and the option to contribute to an RRSP programme
• Paid vacation from day one
• 80% reimbursement of your public transit pass
• A Give & Match programme
• A beautiful office with a golf simulator, a gym, locker rooms and showers

This position requires in‑office presence. We have found that being physically present fosters interactions that positively impact performance. As such, we strongly encourage employees to maintain this presence to fully benefit from the environment.

We may use artificial intelligence (AI) tools to support certain stages of the hiring process, including reviewing applications, analysing resumes and assessing responses, as well as identifying potential inconsistencies or items requiring verification in application materials, based on the information available. These tools support our recruitment team but do not replace human judgement. Final hiring decisions are made by people. For more information on how your data is processed, please contact us.

We collect your information through a secure applicant tracking system with access restricted by role. Data, including resumes and interview notes, are stored within this system. If you wish to withdraw consent or have concerns, please contact us at [e-mail].

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