Sr Frontend Developer

Penbrothers International; Mandaluyong; Remote; PHP 600,000 - 1,200,000; Full time

Job summary

Penbrothers is seeking a Frontend Developer to join our development team, shipping features, building and hardening integrations, and keeping a production system healthy with thousands of daily syncs.

You will work on improving the UI for dispatchers, office staff, and technicians across desktop and mobile, and extend AI-assisted features using Claude API. A small team delivers real customer impact.

Qualifications

• 3–5 years building production web apps with TypeScript and React.
• Experience with PostgreSQL including schema design and row-level security.
• Hands-on REST API integration: OAuth, API keys, JWT, webhooks, pagination, retries.

Responsibilities

• Build features across the stack in React and TypeScript, Postgres, and serverless functions.
• Maintain integrations with third-party APIs (ERP, payroll, GPS, telephony, payments).
• Enhance AI-assisted features using Anthropic Claude API, including prompt design and testing outputs.

Skills

TypeScript

React

REST APIs

OAuth/JWT

Git

Tools

PostgreSQL

Supabase

Vercel

Anthropic Claude API

Job description

Job Description:

About Penbrothers

Penbrothers is an HR & remote talent management partner and one of the fastest-growing companies in the Philippines. We provide talented Filipinos with global opportunities in high-growth startups and dynamic companies, from the comfort of their own homes.

About the Client

Our client is an operations platform for security, alarm, and fire service companies. It sits on top of SedonaOffice, the accounting and service system many of these companies already run, and gives dispatchers, technicians, installers, and customers modern tools without a data migration. The platform handles dispatch and scheduling, a technician mobile app, inventory, fleet, a customer portal, and AI-assisted technician recommendations. It is used every day by live service companies across the Southeast and New England.

About the Role

As a Frontend Developer, you will work as part of our development team to ship features, build and harden integrations, and keep a production system with thousands of daily sync runs healthy. Small team, real customers, and your work reaches users within days.

What You Do

• Build features across the stack in React and TypeScript, Postgres, and serverless functions
• Build and maintain integrations with third-party APIs: accounting/ERP, payroll, GPS and telematics, telephony, SMS, payments, and mapping
• Extend AI-assisted features built on the Anthropic Claude API, including prompt design, tool use, and testing outputs for accuracy
• Improve the user interface for dispatchers, office staff, and field technicians, on desktop and mobile
• Investigate sync issues and vendor API defects, document findings, and write clear notes for non-technical readers
• Write and follow database migrations, row-level security policies, and tests that protect customer data

What You'll Bring

• 3 to 5 years building production web applications with proficiency using TypeScript and React
• Experience with PostgreSQL, including schema design, SQL, and row-level security concepts
• Hands-on REST API integration: authentication (OAuth, API keys, JWT), webhooks, pagination, rate limits, retries, and idempotency
• At least one shipped feature built on a large language model API (Anthropic Claude preferred)
• Experience with Git, pull requests, and working in a codebase someone else started

Nice to Have

• Supabase (Postgres, Auth, Edge Functions, Storage) and Vercel
• UI/UX design skills: Figma, Tailwind, component libraries, accessibility, and mobile-first layouts
• Mobile experience: Capacitor, React Native, or native Android/iOS
• Experience with Twilio, RingCentral, ADP, Verizon Connect, Google Maps, or payment processors
• Background in field service, construction, or security industry software
• Experience using AI coding tools (Claude Code or similar) responsibly in a production codebase

Our Hiring Process & AI Disclaimer:

We use AI tools to streamline our application process—including an initial conversation with an AI Interviewer. All hiring decisions are made entirely by humans: our Talent Acquisition team guides your full candidate journey and makes all evaluation decisions.

You are welcome to use AI for CV refinement and research, but real-time AI assistance during interviews or skill assessments is strictly prohibited to ensure an authentic evaluation.

Read our full AI Disclaimer to learn more

What You’ll Get

At Penbrothers, we are obsessed with creating positive employee experiences. Here you’ll find an environment that nurtures learning and provides opportunities for growth. You’ll have the opportunity to make an impact on fast-growing startups and dynamic companies.

Meaningful work & Growth: We take every opportunity to stretch ourselves and deliver an excellent client experience.

Employee as our biggest asset: We are genuinely invested in our people’s career and welfare.

Global reach & local impact: Get to work with high-growth startups and dynamic companies from the comfort of your own home.

Powering global startups: We’ve created 1,400 Filipino jobs that empower global start-ups to focus on growth.