01
Websites & landing pages
Fast, multilingual marketing sites that rank well and load instantly from the edge.
- Responsive design
- Korean / English i18n
- SEO & structured data
- Serverless edge hosting
Taking new projects for Q4 2026
Web products andAI solutions,built end to end.
Seol Company is a one-person studio. One engineer takes your idea from the first sketch to a running service, then stays on to keep it healthy.
5
Products live
900+
Members on to.duck
2
CVEs credited by Spring
6
Open-source projects contributed
Services
What we can build for you
Small team, full ownership. The same person who designs your system writes the code and answers when it breaks.
02
Web apps & backoffices
MVPs, customer portals and internal admin tools with the APIs and database behind them.
- Product MVPs
- REST APIs & auth
- Admin dashboards
- Payments & paywalls
03
AI solutions
LLM features that work on your own data, wired into the tools your team already uses.
- RAG chatbots on your docs
- Workflow automation
- AI agents & tool calling
- Usage & cost monitoring
04
Cloud & DevOps
Deployment pipelines and infrastructure that stay up without a dedicated ops team.
- CI/CD pipelines
- Kubernetes & GitOps
- Monitoring & alerts
- Cloud cost reduction
Products
Things we've shipped
Services we built and still run. Try them out — they're the best sample of how we work.
iOS app · Web · Backoffice
to.duck
Routines, diary and community for adults with ADHD.
900+ members · on the App Store
- Repeating routines and daily schedules
- Mood and focus diary with monthly insights
- Community for sharing routines and tips
- Push reminders on iOS
- Admin backoffice with stats and broadcast alerts
Web app
Colla
One workspace for team projects.
- Team spaces with invite links
- Feeds for posts, schedule polls and file collection
- Real-time team chat
- Metrics and log monitoring built in
Web tool · Korean
Salary Calculator
See your real monthly take-home pay for 2026.
- Annual or monthly salary input
- National pension, health, employment insurance and income tax
- Dependents and SME tax relief options
- Visual breakdown of every deduction
Web tool
JSON Analyzer
Validate, format, compare and inspect JSON.
- Validator with clear error positions
- Formatter
- Side-by-side diff checker
- Schema extraction
- Light and dark themes
Web game
Speed Coder
Typing practice for developers, in an editor.
- Real code in Python, Java, C and JavaScript
- Live CPM and error count
- Editor-style interface
- Dark mode
Process
How a project runs
- 01
Discovery call
We talk through the problem, users and constraints. No slides needed.
- 02
Scope & estimate
You get a written scope, milestones and a fixed estimate before any code.
- 03
Weekly builds
Working software every week on a preview URL, so feedback comes early.
- 04
Launch & care
We deploy, set up monitoring and stay on for fixes and improvements.
About
Who's behind Seol Company
I build backends and run the infrastructure under them. My day job is a B2B content platform for a global IT research firm; Seol Company is where I take on projects of my own and for others.
- 2025 –
Backend / DevOps Engineer · Global IT market research firm
B2B research portal, data pipelines, internal automation
- 2024 –
Backend & Web Engineer · to.duck
Routine app for adults with ADHD, 10-person team
- 2024
Backend & Infra Lead · Colla
Team collaboration platform
- Open source
Contributor · Spring AI · Spring Data JPA · Fixture Monkey · Apache Seata
CVE-2026-22751, CVE-2026-40966 reported to Spring
Stack
Tools we work with
Frontend
- React
- TypeScript
- Next.js
- React Router
- Vue
- Tailwind CSS
Backend
- Java
- Spring Boot
- NestJS
- Node.js
- RabbitMQ
Data
- PostgreSQL
- MySQL
- Redis
- Apache Spark
- Elasticsearch
AI
- Spring AI
- Gemini
- OpenAI API
- pgvector
Cloud & Ops
- AWS
- Cloudflare
- Docker
- Kubernetes
- Argo CD
- GitHub Actions
- Prometheus
- Grafana
Have a project in mind?
Tell us what you're building and when you need it. You'll get a reply within two business days.