Open to opportunities

Simon Phillip Guillen

@simonphillipguillen

Message

I build and scale full-stack web applications across modern JavaScript ecosystems.

Philippines

Message

What I'm looking for

I'm looking to build and improve web applications where I can own frontend or full-stack delivery, work with modern JavaScript technologies, solve product and performance challenges, and mentor developers.

At BUTN, I own frontend delivery across Stella Maris Academy projects, from design implementation and responsive interfaces to API integration, multi-step forms, testing, AWS Amplify deployments, and vulnerability remediation. I also use AI tooling in VSCode, Copilot, Claude, MCPs, custom agents, and instruction files to support development workflows.

I've built and maintained products including Lodago's event-booking platform, Therapeutic Guidelines' medical subscription platform, BroadPath's Candidate Portal, PushCoin's school-payment app, and multiple Web3 products at Fufu Labs. Across more than 10 years of web development, I've worked in frontend and full-stack roles, led and mentored developers, migrated thousands of legacy records, and delivered applications using React, Vue, Node.js, PHP, cloud platforms, and Web3 APIs.

Experience

Work history, roles, and key accomplishments

Senior Javascript Developer

BUTN

Dec 2024 - Jul 2026 (1 year 7 months)

As the sole frontend developer, handled all frontend work across most projects, including UI implementation, mobile responsiveness, performance optimization, API integration, and deployment to AWS Amplify. Addressed vulnerabilities reported by Dependabot and Snyk, and worked with AI via VSCode and Copilot.

TypeScript Redux React Hook Form Zod Vite Vitest React Testing Library Redux toolkit SWR HTML jQuery NodeJS MongoDB CSS ExpressJS AWS Amplify AI VSCode Copilot Claude

Frontend Web Developer

Lodago

Mar 2024 - Sep 2024 (6 months)

Maintained and implemented new features, resolved bugs, and customized the Lodago app for diverse clients, including high-profile events like MWC Barcelona. Developed custom features for specific companies such as Datadog.

Vue.Js TypeScript SASS Git

Frontend Web Developer

BruntWork

Apr 2023 - Mar 2024 (11 months)

Worked with Therapeutic Guidelines, an Australian subscription-based platform, implementing critical features including PWA capabilities, optimizing code, ensuring mobile responsiveness, and addressing bug fixes. Ensured rigorous testing before deploying to Microsoft Power Platform.

Redux React Native jQuery HTML SASS Cucumber BrowserStack Microsoft Power Platform Git

Full-stack Web Developer

Fufu Labs

Feb 2021 - Mar 2024 (3 years 1 month)

Managed multiple projects including EXNT.io, The OTC Room, Jpegarmy, Elondoge.io, and Gatherdao. Led a team of developers, overseeing assignments, conducting code reviews, and providing mentorship.

MongoDB ExpressJS NodeJS Web3.js Socket.IO TypeScript SASS Bootstrap Jest Laravel Material UI Ant Design Redux AWS GCP Git Nginx Moralis Alchemy Infura

Frontend Web Developer

BroadPath

May 2019 - Feb 2024 (4 years 9 months)

Maintained and enhanced the Broadpath Candidate Portal, redesigned key elements, managed applicant data in Salesforce CRM, and served as chat support agent. Ensured mobile responsiveness and implemented UX enhancements.

Salesforce Visualforce Apex jQuery SOQL SOSL

Frontend Web Developer

PushCoin

Sep 2018 - Jan 2019 (4 months)

Enhanced and maintained the PushCoin app for school payment processes, implemented new features, refined user experience, and resolved bugs. Successfully completed an initial project milestone on Upwork.

TypeScript Bootstrap Vue Vuex Git

Full-stack Web Developer

FieldTec Pty Ltd.

Nov 2014 - Jul 2018 (3 years 8 months)

Developed FormBird, a platform for building custom pages and forms from JSON data, using Angular components. Led data migration from legacy system to FormBird, converting SQL Server records to JSON in MongoDB.

MongoDB Express AngularJS NodeJS Elasticsearch Jasmine Bootstrap Gulp Git

Full-stack Web Developer

Offsourcing Inc.

Jul 2013 - Nov 2014 (1 year 4 months)

Contributed to maintenance and development of new features for Beyond the Rack, a Canadian e-commerce platform. Collaborated with senior developers in Canada to ensure seamless feature integration.

CodeIgniter HTML CSS jQuery MySQL Mercurial

Full-stack Web Developer

Twidl Inc.

Nov 2012 - Feb 2013 (3 months)

Served as full-stack developer for LifeBit, focusing on API development with 90% backend work. Emphasized test-driven development, ensuring comprehensive test suites for each module.

AngularJS CoffeeScript Grunt PHPUnit Git