Co-founder & CTO. A voice trading workspace for web and macOS: ask for market context, review an order, revise it, and approve execution on your exchange account. The product also provides voice technology for partner platforms.

• Own the path across languages and surfaces. Python orchestration, Spring Boot services, native Swift UI, and the web experience connect market data, account state, and order workflows.
• Separate interpretation from execution authority. Natural language prepares the action; explicit user approval and deterministic checks govern execution. Market identity, quantities, and account state stay part of the transaction contract.
• Build beyond the conversation. Exchange integration, real-time updates, onboarding, packaging, and deployment make the system usable outside a development session.

Python · Java / Spring Boot · Swift / SwiftUI · TypeScript · PostgreSQL / WebSocket

GitHub organization

ssuAI · ssuMCP · ssuAgent · ssu-ai-service

Students search university information and use their own academic, LMS, and library data through a web app or an agent. I built the four-service platform, from connectors and orchestration to deployment and observability.

• Campus workflows through both a web app and an MCP server. Expose 52 MCP tools for university information and academic, LMS, and library tasks, usable from clients such as Claude Desktop and Cursor. REST and MCP share business rules; LangGraph manages specialist routing, persistent conversations, and approval before writes. MCP connection guide
• 100 competing reservations → 1 upstream write. An intent queue and same-seat suppression protect the university system. Verified with 100 concurrent requests against WireMock; this is a reduction in external writes, with a deliberate latency trade-off. Load-test evidence
• Built and operated the delivery path. ARM64 images are built in GitHub Actions and published to GHCR. Until October 2026 ArgoCD rolled them out to k3s, with Prometheus/Grafana, Tempo, and Loki connecting metrics, traces, and logs; fault injection verified circuit-breaker isolation and recovery. To fit a free-tier budget, I then moved the services to one VM running Docker Compose, where a timer pulls the newest image, checks public health, and rolls back on failure. Observability & incident records · Platform decision

Java / Spring Boot · Python / LangGraph · PostgreSQL / Redis · Docker Compose / GHCR · OpenTelemetry

Web app · Chat

Backend, AI, and platform. A founder describes a problem and solution once; the team product creates a landing page, five social cards, copy, and a Meta ad, then brings back Insights, visits, and consented early-access reservations.

Built the durable workflow behind it: PostgreSQL jobs, SKIP LOCKED, leases, operation keys, and checkpoints keep generation, ad creation, and result collection independent of a browser tab, with controlled retries around external side effects. Architecture

🏆 Manifest Special Award · UNITHON 2026.

Next.js · Supabase / PostgreSQL · Anthropic · Meta Marketing API

Organization · Source & team roles · Live service

A summer survival map over 150k+ public points of interest, with nearby shade, shelters, and live community reports. I built the data ingestion, spatial backend, application, and infrastructure.

• Found the bottleneck in the execution plan. Spatial indexes were already working; expired reports were still scanned for every scored search. Indexing their expiry filter cut SQL execution time 361 → 172 ms (~52%) on the same synthetic dataset: 300k places and 210k reports, measured locally under QEMU. EXPLAIN comparison
• Kept data and updates repeatable. Idempotent ETL, PostGIS radius/nearest-neighbor queries, SSE reports, and infrastructure as code connect ingestion to the map.

Spring Boot · PostgreSQL / PostGIS · SSE · Terraform / Oracle Cloud

Source & architecture · Open the map

Frontend, roommate domain, integration, and application infrastructure. Built explainable recommendations across eight lifestyle dimensions, recruitment/application flows, and one-to-one/group chat. Owned the application's Spring Boot/MySQL deployment, Helm configuration, network isolation, image-digest checks, and backup/restore gates.

🥈 Silver Prize · Soongsil University CS Software Competition 2026. The team delivered the dormitory eligibility and roommate experience together.

Spring Boot · Next.js · MySQL · WebSocket · Helm

Organization · Open the service

Backend, data, modeling, and integration. A tourism-data product that connects festival planning with visitor discovery. The model forecasts regional visitor-days, with D−30 information constraints, prediction ranges, and contributing factors.

🏅 Excellence Award · 2026 Tourism Data Utilization Contest (Korea Tourism Organization).

• WAPE 4.256% → 3.939%. A seasonal baseline plus LightGBM residual model improved WAPE by 7.43% relative on a retrospective time holdout of 4,959 region-days. Model card
• Forecast coverage 30 → 98 out of 100 real events. Corrected date-window and administrative-region history handling to make more events usable without changing the prediction target to festival attendance. Decision record
• Keep generated reports grounded. The API rejects unsupported figures; scheduled retraining adopts models that pass five acceptance gates, and falls back to a clearly flagged provisional model only when the current one is about to expire.

FastAPI · LightGBM / pandas · Next.js · Claude · Scheduled data pipelines

Source · Live service

Agent backend and file-operation boundaries. A local-first workspace for HWP, Office, and PDF. Built the FastAPI sidecar, agent orchestration, approvals, file edits/undo, and knowledge synchronization. Retrieval exposes source evidence; approved edits produce and verify a new file while preserving the original.

FastAPI · Electron · SQLite · Local LLM

Organization · Product repository · Agent backend · Run locally

_{Performance figures link to their measurement conditions. Project roles distinguish individual ownership from team delivery.}