Karl Christian AjeroFull Stack Developer
Professional Experience
Flying Tigers Express, Full Stack Developer
09/2025 – Present
  • •Lead development for the Business Portal. Built key features, including bulk shipment import, partner dashboards, and waybill generation workflows.
  • •Architected the Business API integration layer — REST endpoints for bookings, batch tracking, webhook registration, rate limiting, and sandbox isolation — enabling programmatic shipment management for enterprise clients.
  • •Implemented Business Team Wallet on the backend and customer app: wallet activation, Xendit-backed top-ups, shared balance across team members, and default booking payment method configuration.
  • •Built centralized activity logging with entity-scoped metadata (shipments, businesses, invoices, tickets, API keys) and an Admin Ops global activity view with category filters, search, and human-readable formatting.
  • •Integrated third-party logistics workflows (e.g. Lalamove, Consegnia) via integration batches and webhook handlers, plus partner-facing webhook management in the Business Portal.
    • Sanct, Co-Founder & Technical Lead
    12/2023 – 09/2025

    Software startup building web platforms for clients

  • •Co-founded Sanct, a DTI-registered startup that designs and builds websites and web platforms for clients. Led the technical side, from system architecture to delivery.
  • •Built and delivered multiple client websites, including a real estate website and our biggest project, DepEd MPS.
  • •Technical lead for DepEd MPS, a Mean Percentage Score monitoring platform for DepEd Region X, owning system architecture and engineering delivery for regional score encoding, section management, and school/division performance review.
  • •Defined the technical roadmap and led the engineering team in shipping features aligned with how DepEd divisions and schools work, from educator score entry to division-level oversight and reporting.
  • •Architected a scalable system for high-volume education data, now supporting 50,000+ students, 200,000+ encoded scores, and 2,000+ active educators, and expanding to other regions in the Philippines.
  • •Set engineering standards around role-based access, encode-time data validation, and division/school aggregation, prioritizing security, data integrity, and maintainability for government use.
    • Symph, Full Stack Developer Intern
    04/2023 – 09/2023
  • •Contributed to the development of LessonPlanner, an AI-driven platform designed to automate and simplify lesson planning for educators.
  • •Built features for SnapProduct, a generative AI tool that transforms standard product photos into professional, photoshoot-ready images.
  • •Collaborated within cross-functional teams to develop, maintain, and enhance features across the full stack for various client and internal products.
  • •Maintained and optimized multiple ongoing web applications, ensuring code reliability and a smooth user experience across different project environments.
    • Freelance Full Stack Developer, Independent / Contractual
    2021 – 2022
  • •Designed and built websites and small web applications for individual and small-business clients, handling requirements gathering, development, and deployment independently.
  • •Delivered a mix of marketing/portfolio websites, web apps with backend and database integration, and e-commerce sites, working directly with clients from scope to launch.
  • •Managed the full project lifecycle solo — client communication, UI implementation, backend/API setup, and post-launch fixes — building early experience in end-to-end ownership later applied in production roles.
    • Education
    Bachelor of Science in Computer Science, Cebu Institute of Technology - University
    2022 – 2026
    STEM Engineering - Senior High, Mater Dei College
    2020 – 2022
    Skills
    Frameworks & Libraries

    React, Next.js, Angular, AngularJS, Vue.js,

    Deployment & DevOps

    GCP, AWS, Vercel, Railway,

    GitHub Actions, CI/CD

    Backend Frameworks

    Node.js, Express.js, NestJS, Django, FastAPI

    Databases

    MongoDB, MySQL, PostgreSQL, Supabase, Firebase

    Mobile Development

    React Native, Expo, Android Studio, Swift, Flutter

    Projects
  • •Built TreeTrace, a web app for building, comparing, and identifying familial connections through uploaded family trees, using Next.js, NestJS, MongoDB, custom authentication, and the Gemini API.
  • •Built AgriVision, a mobile app that uses deep learning and computer vision to detect lettuce diseases from images, helping farmers and agriculturists diagnose plant health and act early to prevent crop loss. Developed with React Native, a CNN-based model, and Supabase as the backend.
  • •Built the mobile version using React Native, NativeWind, Expo, and Appwrite. Contributed to the web version as part of a team. A cross-platform healthcare app for securely managing medical records and healthcare identification.
    • Research
    Personal Back Squat Form Correction System Using Mediapipe Pose Estimation and QLoRa-Fine-Tuned Language Models.
  • •Scope: Developed an AI-driven system that utilizes computer vision and fine-tuned LLMs to provide real-time feedback and correction for athletic form.
  • •Achievement: Presented this research at the 12th International Conference on Education and Training Technologies (ICETT) in Seoul, South Korea, in May 2026.