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Skills

  • API
  • C#
  • Programming
  • Python
  • API Development
  • JSON
  • Next.js
  • PostgreSQL
  • SaaS
  • Software Development
  • SQL
  • C++
  • Docker Software
  • Open Source
  • Chatbots

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Services

  • AI Automation & LLM Integration

    $55/hr Starting at $500 Ongoing

    Dedicated Resource

    I build AI-powered automation systems that save time and reduce manual work for your business. As the developer behind checkapi.io — an API monitoring SaaS I built and operate independently — I bring...

    APIAPI DevelopmentC#C++Chatbots

  • FastAPI Backend Development & REST API

    $55/hr Starting at $500 Ongoing

    Dedicated Resource

    I build fast, production-ready backend systems using Python and FastAPI. As the sole developer of checkapi.io — a live API monitoring SaaS — I've built and maintained a full backend stack in production,...

    APIAPI DevelopmentC#C++JSON

  • Full-Stack Web Development with Next.js

    $5/hr Starting at $500 Ongoing

    Dedicated Resource

    I build modern, performant web applications using Next.js 14 and React. From SaaS dashboards to admin panels and customer-facing products, I handle the full stack — frontend through backend — with clean...

    APIAPI DevelopmentC#Docker SoftwareJSON

  • SaaS&MVP Development From Idea to Lanuch

    $5/hr Starting at $500 Ongoing

    Dedicated Resource

    I build SaaS products and MVPs end-to-end, from architecture to deployment. I'm not just a developer — I'm a product owner. I independently built and operate checkapi.io, an API monitoring SaaS with paying...

    APIC#Docker SoftwareNext.jsPostgreSQL

About

Full-stack developer & SaaS founder building AI automation systems and scalable web products.

I'm Sewon Jeon, founder of Axiom Technologies and the developer behind checkapi.io — an API monitoring SaaS I independently built, launched, and operate.

I specialize in AI-powered automation, full-stack web development, and SaaS product engineering. My stack centers around Python, FastAPI, Next.js, and Claude API, with hands-on experience shipping production systems across multiple industries.

Selected work:
- checkapi.io: API monitoring SaaS with payment system, dashboard, and alert pipeline (FastAPI + Next.js + Celery + Redis + PostgreSQL)
- Real-time 1:1 quiz matching system with AI-generated questions via Claude API, delivered within 12 hours (Supabase Realtime + Vercel)
- MES system for a manufacturing client using Firebase PWA with LOT tracking and quality management
- 6-channel SNS auto-publishing pipeline (Notion → YouTube / Instagram / TikTok / Threads / X / Reddit) using n8n + Docker
- Meta API + Claude marketing automation with weekly performance reports and AI-generated content drafts

I take ownership of projects from spec to deployment and stay accountable post-launch. Every engagement includes 1 month of free bug fixes after delivery.

Work Terms

Hours: Monday–Saturday, 9AM–10PM KST (UTC+9). Typically respond within a few hours.

Communication: Prefer async via Guru messages. Available for calls by appointment.

Delivery: Milestones agreed upfront. Demo or staging link provided before final delivery.

Payment: Milestone-based payments preferred. Fixed-price for well-defined projects, hourly for ongoing or exploratory work.

Post-delivery: 1 month of free bug fixes included on all projects.