Steve Saintil · Full-stack developer, UI/UX, graphic & video

About

I build what I design, and design what I build.

I'm a full-stack and Flutter engineer in Montreal. In 2026 alone I shipped and maintain four production systems, including a short-video social app on both app stores, a B2B commerce platform with its own phone-answering system and mobile app, and a multi-tenant website and booking SaaS.

I own the UI/UX of everything I ship, from user flows and prototypes in Figma to the production interface, and I make the visual assets (Photoshop, Illustrator) and edit the product videos (Premiere Pro, After Effects, DaVinci Resolve). I test every UI change in a real browser and back the work with automated tests and CI.

Location: Montreal, QC, Canada
Work: Authorized to work in Canada · remote for US companies (contractor/EOR)
Languages: English & French
Education: Palm Beach Community College, Web Design

Selected projects

Products I've built and still run.

Multi-tenant SaaS · web

TechlyStack

Lead Software Engineer · Apr 2026 – Present

A multi-tenant platform that builds, hosts and bills websites for local businesses, with online booking and deposits, subscription billing and an SEO engine. It runs live service businesses today.

Framework-free PHP 8.2 + MySQL: my own router, middleware pipeline, view engine and tenant isolation.
Website builder with 38 editable content blocks, inline editing, themes, French/English sites and custom domains.
Online booking with Stripe deposits (multi-service cart, CAD/USD), subscription billing with setup fees and Stripe Connect fee splits.
LLM features (copywriting, SVG logos, image captions) behind one router with a platform-wide daily budget and per-tenant credits.
Dependency-free AWS SigV4 client for S3 / Cloudflare R2 / Backblaze B2; SSRF guard with IP pinning, HTML/SVG allow-list sanitizers, CSRF on every form.

~228k lines of PHP
~990 routes
57 PHP test scripts + 36 Playwright specs

PHP 8.2
MySQL
Redis
Alpine.js
Tailwind
Stripe
Google APIs
Playwright

Visit techlystack.com (opens in a new tab)

Mobile app · iOS + Android

VOOCONNECT

Lead Mobile & Backend Engineer · 2021 – Present

A short-video social app (camera, editor, live streaming, chat, in-app purchases) rebuilt from a native Swift iOS app into one Flutter app on both stores, with a Node.js backend and a React admin.

~155k hand-written lines of Dart, 29 feature modules, clean architecture with BLoC/Cubit, go_router and 5 languages.
Video camera and editor (FFmpeg), stories, live streaming and walkie-talkie (Agora), real-time chat (Socket.IO), gifts and in-app coin purchases.
Node.js/Express + MongoDB Atlas backend and a React + TypeScript + Vite admin dashboard.
Moved all media off a locked Cloudinary account to Cloudflare R2 with nothing lost; wrote the legacy MySQL to MongoDB migration, rehearsed on staging with 515 MB of media.
Cut the Android download from 565 MB to 139 MB; 268 unit/widget test files, Maestro flows and Codemagic CI to both stores.

~155k lines of Dart
29 feature modules
5 languages

Flutter
Dart
BLoC
Node.js
MongoDB
Socket.IO
Agora
FFmpeg
React
TypeScript

vooconnect.com (opens in a new tab) App Store (opens in a new tab) Google Play (opens in a new tab)

B2B portal · web + mobile

Members Only Shop Supplies

IT Technician / AI Developer · Feb 2025 – Present

A B2B ordering and operations platform for an auto-body and paint supply distributor in Paramount, California, plus its iOS and Android app. I am the sole engineer: I designed, built and run all of it.

Membership storefront with member pricing, a 3-step checkout, company accounts and renewals with automatic follow-up on declined payments.
Card payments on Sola/Cardknox, plus Zelle and card on file.
ERP sync with the OMS/Pavo API and a nightly day-close that invoices the day's orders automatically; PDF invoices, pick slips and a truck-loading planner.
Phone answering: a Node.js voice bridge connecting the phone line (Telnyx) to a live voice model that reads the platform's knowledge base; chat with hand-off to staff.
iOS and Android app (Capacitor, push notifications) signed and shipped through Codemagic CI.

~220k lines of PHP
~154 tables
972 commits (May–Oct 2026)

PHP 8.2
MySQL
Node.js
Telnyx
Twilio
Sola/Cardknox
Capacitor
Codemagic
Playwright

membersonlyshopsupplies.com (opens in a new tab) App Store (opens in a new tab) Google Play (opens in a new tab)

Websites I designed & built

Screenshot of the My House Experts website

My House Experts Home-services website in French and English with a 4-step instant estimate, a multi-service booking cart, Stripe deposits and Google Calendar sync. myhouseexperts.com (opens in a new tab)

RushNDrop Urgent parts pickup and delivery: instant-price flow, admin quote tool and a $10 booking deposit with automatic refunds of duplicates. rushndrop.com (opens in a new tab)

WAE Transport Corporate website for a freight brokerage, with a full-width truck slider, service pages and a quote request form. waetransport.com (opens in a new tab)

Screenshot of the Western Auto Body website

Western Auto Body Collision-repair shop website with real shop photography and a multi-step preliminary estimate form. westernautobodyinc.com (opens in a new tab)

UI/UX case studies

The problem, what I did, what shipped.

Website builder UX

A website builder non-designers can use

TechlyStack · product design + front end

Problem

Local business owners edit their own sites. The builder had to stop them from breaking the layout or making text unreadable, without a designer in the loop.

What I did

Click a block in the live preview to edit it; inline editing and draggable hotspots.
Autosave that never reloads the preview mid-edit; it refreshes only on close, page switch or a structural change.
Theme controls (brand colours, heading/body fonts, text size, corner radius, gradient) on top of 38 content blocks.
Readability guardrails at render time: forced contrast and minimum overlays on photo heroes.
A reduced-motion-safe "Wow" animation style, and a design-system refresh across 87 admin views.

Result

Shipped and in use on the live client sites listed above.

Mobile

One app, both stores

VOOCONNECT · UI + engineering

Problem

The original app was iOS-only (native Swift, ~70k lines), so Android users could not use it, and the Google Play listing had been removed.

What I did

Redesigned and rebuilt it as one Flutter app: feed, camera and editor, stories, live streaming, chat and gifts.
Feature flags controlled from the admin panel, and 5 languages (EN, FR, DE, ES, PT).
Kept the Swift app running against the same backend during the rebuild.

Result

Live on the App Store and Google Play from one codebase; Android download cut from 565 MB to 139 MB.

Booking flow

Price and book several services in one visit

My House Experts · booking widget on TechlyStack

Problem

Customers needed to see a price and book right away, often for more than one service, in French or English.

What I did

A 4-step widget: service, options, date and time, confirm.
A multi-service cart that takes one deposit for the whole visit, with per-city travel surcharges shown as their own line.
Confirmation emails to the customer and the owner, and an embeddable version for other websites.

Result

Live on myhouseexperts.com with Stripe deposits and Google Calendar sync.

B2B operations

Ordering and back-office for a supply distributor

Members Only Shop Supplies · sole designer + engineer

Problem

Orders, products, inventory and invoices had to stay in sync with the distributor's ERP, and staff needed print-ready paperwork and a clear plan for each truck run.

What I did

Member storefront with a 3-step checkout and renewal reminders (every 3 days, 3 at most) after a declined payment.
Invoices and pick slips as PDF and print, and a four-tab truck page that tells drivers what to load per run.
A nightly day-close that invoices the day's orders through the OMS/Pavo API.

Result

After the October 2026 day-close fix, three runs invoiced 58 waiting orders and a repair pass invoiced 10 more.

Graphic design

Brand, packaging, print and ad creatives.

Logos, product labels and dielines, flyers and social ads for real businesses, made in Photoshop and Illustrator. Select any piece to view it full size.

Video work

Explainers, motion graphics and interactive video.

Client explainer videos since 2016, and today the full pipeline from script and storyboard to edit, motion graphics, captions, sound mix and every social cutdown (16:9, 9:16, 1:1).