Liu Lbyn

Full-stack engineer with 5+ years of experience building production web applications, internal platforms, and backend services. Proficient in React, JavaScript/TypeScript, GraphQL, Node.js, and Python. Comfortable owning features end-to-end — from database schema design and API layer through to polished, responsive UI. Experienced deploying and operating services on AWS.

Full-Stack Engineer - TigerCampus - Remote, Freelance

(2025-01)

TigerCampus is an education management platform serving tutoring companies, covering scheduling, billing, client CRM, and automated communications.

• Built and maintained a large-scale React + React-Admin admin application (deployed via AWS Amplify) covering 20+ resource modules: appointments, recurring schedules, tutors, students, clients, retainers, billing rates, HR analytics, and more.
• Implemented a custom DataProvider backed by Apollo Client that maps Hasura GraphQL responses to React-Admin's expected schema, including custom filters, field mappings, and error handling.
• Implemented a custom AuthProvider using oidc-client-ts for silent-refresh OIDC authentication, with role-based UI authorization (RBAC) using ra-rbac.
• Built a fully interactive appointment calendar view using @fullcalendar/react with resource-timeline, time-grid, day-grid, and list plugins — supporting timezone selection, per-tutor color coding, and inline filter drawers.
• Delivered pixel-perfect, responsive layouts using Material UI, composing reusable form components and editable data grids for complex nested data structures.
• Designed and evolved PostgreSQL schemas for the core TCS database, CRM, messaging (GenspaceAgent), and mail databases, writing forward and backward migrations using Hasura CLI.
• Built and deployed AWS Lambda microservices (Python/Flask) as Hasura Action handlers, including: SleekFlow connector (bidirectional sync between appointment state and WhatsApp CRM labels, handling webhook events from SleekFlow and pushing updates back via its REST API), Appointment cron (scheduled job to auto-assign billing rates to recurring appointments using GraphQL queries, with Zapier webhook notifications for downstream workflows), Auto-scheduling service (Flask endpoint that triggers an A
• Secured all internal service endpoints with shared secret header validation and scoped GraphQL permissions per role.

Software Developer - Suzhou Yingshu Intelligent Technology

(2020-02 - 2022-08)

• Delivered full project lifecycle across multiple client systems: requirements, design, development, and handoff.
• Designed RESTful APIs and integrated third-party services to ensure cross-system data consistency.

B.Eng. - Electronic Information Engineering (2015-01 - 2019-12)