Joseph Karl Crisostomo

Manila, PH (UTC+8, overlaps US hours daily) · joseph.dev.ph@gmail.com · +63 960 4431 908 Portfolio: https://kathulhur.github.io · GitHub: https://github.com/kathulhur

Summary

Full-stack engineer who has fully leaned into AI-assisted development. I build real-time, data-heavy web apps and React dashboards that ops teams actually use, and I ship them end to end — from requirements to prototype to deploy to feedback. I pilot agentic tooling like Claude Code to accelerate development velocity while using hands-on coding experience to catch when the AI drifts off course. Strong communicator who turns messy operational workflows into clean, maintainable software, and comfortable translating requests from non-technical teammates into working systems.

Skills

• Languages: JavaScript, TypeScript, Python, Ruby
• Frontend: React, Next.js, TypeScript, Leaflet, HTMX, Turbo, HTML, CSS
• Backend: Node.js, REST integrations, WebSocket/SSE, Django, Ruby on Rails
• Databases: PostgreSQL/RDS, Redis (ElastiCache)
• Cloud / Infrastructure: AWS (RDS, S3, EKS, CloudFormation, CodeBuild, ECR, ElastiCache, Amazon MQ), Docker, on-premise Linux (Ubuntu), CI/CD pipelines
• AI-assisted development: Claude Code (CLI), Claude Design
• Testing / Tooling: Playwright, Grafana K6, Git
• Strengths: Resourceful and adaptive (learns new tools fast), technology-agnostic, strong written/spoken communicator across backgrounds

Experience

Backend Developer — DOST Advanced Science and Technology Institute (DOST-ASTI)

On-site · Feb 2024 – March 2026

• Built and deployed backend systems on scalable infrastructure, integrating RDS (PostgreSQL) as the core database, ElastiCache (Redis) for caching, and Amazon MQ as a message broker.
• Implemented secure, repeatable deployments by automating infrastructure provisioning with AWS CloudFormation and managing containerized (Docker) services across on-premise Linux (Ubuntu) and AWS.
• Built an automated build pipeline (source in S3, container builds in CodeBuild, images in ECR) and orchestrated containers with AWS EKS — eliminating manual deployment steps.
• Initiated unit testing from 0 to ~90% code coverage, improving system maintainability and integrity; ran automated smoke and load testing with Grafana K6.
• Performed database query optimization through in-depth inspection and root-cause analysis.

Web Developer (Intern) — Dashlabs.ai

Remote · Aug 2022 – Sept 2022

• Contributed to maintenance of the platform's Patient Management Service.
• Handled customer queries across multiple channels (email, chat).

Projects

Kuryente Watch — https://infanta.kuryentewatch.app

• A community web app that crowdsources near-real-time electricity grid status so citizens can see outages and advisories at a glance and plan around them.
• Built fully with agentic AI (Claude Code + Claude Design); I piloted the build, using raw-coding experience to catch when the AI drifted off course.
• Onboarded several barangay "scouts" reporting local outages and earned strong community support and attention online.

AI-as-a-Service Platform (DOST-ASTI)

• Designed a platform standardizing how AI models are developed, deployed, and served — including a model/dataset repository and a feature to easily expose hosted models via APIs.
• Cut AI-model integration from ~2–3 months to a matter of days by replacing duplicated, ad-hoc deployment work with a standardized process.
• Built with AI assistance but hand-written where it counts — sharpened core coding, software development, and architecture skills.

Education

B.S. in Computer Science — Polytechnic University of the Philippines

2019 – 2023