Principal Frontend App Developer (Onsite in Philadelphia, PA) Face to face Interview

equired Skills & Experience

Technical Expertise

Minimum of 8 years of professional frontend engineering experience

3+ years operating in a Principal, Staff, or Lead Engineer capacity with direct reports.

Deep expertise in React.js, Next.js, TypeScript, JavaScript, and modern frontend architecture patterns.

Strong experience building scalable applications using React Native.

Experience integrating headless CMS platforms, preferably Sanity.io.

Experience implementing authentication and identity solutions using OAuth2/OIDC platforms such as FusionAuth, Auth0, Okta, or Azure AD.

Strong understanding of frontend state management, data-fetching, and caching architectures (React Query, Redux Toolkit, Zustand, Apollo, etc.).

Expertise in responsive design, accessibility standards (WCAG 2.1+), and frontend performance optimization.

Experience building and maintaining enterprise design systems and component libraries.

Architecture & Systems

Experience designing and supporting multi-brand, multi-tenant frontend platforms.

Strong understanding of microservices architectures and GraphQL/REST API integration patterns.

Experience with Azure cloud services including App Services, Static Web Apps, CDN, and Blob Storage.

Familiarity with CI/CD pipelines, containerization, and modern deployment workflows.

Experience implementing frontend observability and monitoring solutions such as Datadog, Sentry, New Relic, or OpenTelemetry.

Understanding of secure application development and regulated environment considerations.

Leadership & Collaboration

Proven ability to mentor engineering teams and influence technical direction across organizations.

Strong collaboration skills across product, UX, platform engineering, security, and executive leadership teams.

Excellent communication skills with the ability to translate complex technical concepts into business outcomes.

Technology Stack

React.js / Next.js

React Native

TypeScript

Sanity.io

FusionAuth

GraphQL / REST APIs

Azure Cloud Services

Storybook / Design Systems

GitHub Actions / Azure DevOps

Datadog / Sentry / OpenTelemetry

Preferred Qualifications

Experience building applications within healthcare, healthcare technology, or other regulated industries.

Familiarity with HIPAA, PHI handling, HITRUST, PCI-DSS, or related compliance frameworks.

Experience supporting multilingual and internationalized digital platforms.

Familiarity with AI/ML-driven personalization, conversational UI, or intelligent engagement experiences.

Exposure to Flutter or legacy hybrid mobile frameworks.

Experience with Storybook, Figma integration workflows, and design token management.

Experience with micro frontend architectures and edge delivery platforms.