Oli Treadwell (he/him) olitreadwell

Oli Treadwell

Senior software engineer and accessibility advocate. Ten plus years building for the web, mostly in React, TypeScript, and Ruby on Rails.

Current: Senior Software Engineer at Numeral Studio. Lead developer on a creative agency's brand site, delivered through Numeral Studio. Lead front-end developer on a regulatory reporting and compliance platform (React, TypeScript, Electron, Playwright end-to-end testing, Radix UI primitives, accessibility tests in CI). Contributing engineer on the studio's other recent product surfaces.
Engineering practice (Numeral Studio): Codified the studio's existing best practice for new client projects into a shared monorepo template (Next.js 15, React 19, TypeScript, Tailwind, Vitest, Playwright, Storybook, Turborepo). Captured patterns the team had already proven across many client engagements and made them the default starting point. Cuts project initiation time by around 30%, saving days per kickoff for both the team and the client.
Independent work (Habitual Genesis, 2016–present): Recently shipped price-to-impact, a Chrome extension that nudges you to donate to high-impact charities while you shop online. Two interventions: divert a planned purchase to a charity equivalent, or round up the cart and donate the difference (TypeScript, MV3, GiveWell-derived data, MIT licensed). Also contributing back to ro-savage/nz-tech-events, a community Rails app popular with the local tech community: CI quality gates, structured-data SEO, shared model concerns, test coverage for the password-reset and digest-job flows.

Multi-brand paywall (2017–2019). Built the brand-agnostic paywall and rule engine used across 26 media brands at a major publisher. Subscriptions doubled year over year at two flagship titles. End-to-end testing approach written up on the company tech blog: End-to-End Testing the Condé Nast Paywalls.
Rewards platform re-architecture (2019–2020). Led the front-end migration from Rails to React with a Storybook design system. Customer engagement lifted 15%. Page load dropped 30%.
Engineering team capacity building (2015–2023). Spent eight years building engineering team capacity at enterprise companies across the USA through structured technical training, ongoing mentoring, and code-review-based coaching of hard and soft skills. Worked directly with engineering teams at Fortune 100 organisations, including ~400 engineers at Amazon. Hundreds of pull-request reviews directly shaped how engineers ramped on new stacks and shipped production work.

Daily: React, TypeScript, Next.js, Node.js, Electron, Playwright, Radix UI, Storybook, Vitest, GitHub Actions.

Comfortable: Ruby on Rails, PostgreSQL, Python, Tailwind, shadcn/ui, Turborepo, Bun, MV3 Chrome extensions.

Practising: Accessibility (WCAG 2.1/2.2, ARIA, screen-reader testing in CI), inclusive design, design-system thinking.

End-to-End Testing the Condé Nast Paywalls — company tech blog, 2018
Past speaking: Refresh Austin, Silicon Beach Melbourne, Austin on Rails ethics panel, General Assembly Congress Austin