Experience
Summary
| Period | Organization | Role | Description |
|---|---|---|---|
| 2025.09 – 2026.09 | Avanade — Microsoft Technical Presales & Deployment (TPD) | Cloud Solution Architect · Partner Technical Consultant, Azure Data & AI | Architecture design and review for APAC ISVs, and 1:1 technical consulting for Microsoft partners. |
| 2023.04 – 2025.08 | Ourcoms Co., Ltd. | Data Platform Engineer | Six production data platform engagements for KT, KT Skylife, Hana Bank, and Corea Insurance Solution. |
| 2021.11 – 2022.02 | National Information Society Agency (NIA) | Intern, Public Data Department | Built data preprocessing pipelines and Open APIs for public data release. |
| 2020.12 – 2021.02 | AIMMO Co., Ltd. | Data Labeler (contract) | Labeled and preprocessed raw image data for machine learning training. |
Two roles at Microsoft TPD
Cloud Solution Architect — ISV Success
Technical onboarding and architecture support for APAC ISVs listing and selling on the Microsoft Commercial Marketplace
- Ran 10+ Architecture Design and Review Sessions (ADS/ARS) per month; reviewed 60+ ISV Azure architectures in six months
- Advised on offer listing, transactable readiness, and Azure architecture validation
- Advised on packaging strategy by delivery model (SaaS / Managed Application)
- ADS = redesign an on-premises solution into a Marketplace-ready Azure architecture; ARS = validate compliance and deployment readiness
Stack: App Service, Functions, AKS, Container Apps, VMs, Azure SQL, PostgreSQL, Cosmos DB, Blob Storage, Entra ID, RBAC, Key Vault, Front Door, WAF, Managed Applications, ARM templates
Partner Technical Consultant — Azure Data & AI
Sole technical owner of 1:1 presales and deployment consulting for Microsoft AI Cloud Partner Program partners
- Owned the full lifecycle: intake → scoping → research → session delivery → monitoring → closure
- 20+ engagements per month, 120+ in six months, average customer and partner satisfaction 4.75 / 5.0
- Guided 20+ partners from design to production deployment and resolved 60+ technical blockers
- Hardened six partner solutions to production-ready posture across security, cost, and performance
Stack: Microsoft Foundry, Copilot, Copilot Studio, Azure OpenAI, Azure AI Services, Microsoft Fabric, Data Factory, Synapse, Databricks, Cosmos DB, PostgreSQL, ADLS Gen2, Purview, Power Automate, Dataverse, Power BI
Data platform projects
PPAS backup & recovery / data lakehouse
KT
Cut KT's PostgreSQL (PPAS) backup storage from 150TB to 7.53TB (about 95%) with Parquet on HDFS organized as Apache Iceberg tables.
- Problem
- Full PostgreSQL (PPAS) backups consumed 150TB.
- Design
- Extracted with Sqoop, stored as Parquet on HDFS, and organized as Apache Iceberg tables. Tiered backups into hourly, daily, weekly, and monthly retention to balance retention and cost.
- Rationale
- Chose Iceberg over plain Hive tables for snapshot isolation and schema evolution, so history never has to be rebuilt when source schemas change.
- Result
- Backup storage cut from 150TB to 7.53TB (about 95%). Columnar Parquet improved recovery speed and storage efficiency.
- Stack
- Apache Iceberg, Parquet, HDFS, Sqoop, Hive, PostgreSQL
Real-time analytics platform enhancement
KT Skylife (7.5M households)
Moved KT Skylife's real-time analytics platform for 7.5M households from CentOS 7 to a Rocky Linux 8 HA architecture with zero downtime and a 20-node scale-out.
- Problem
- A real-time analytics platform serving 7.5M households ran on end-of-life CentOS 7.
- Design
- Migrated to a Rocky Linux 8 HA architecture and scaled out 20 distributed servers. Kafka/Flume ingestion → Hadoop/Spark processing → ELK monitoring.
- Rationale
- RHEL binary compatibility let existing Hadoop/Kafka builds run unchanged; a node-by-node cutover held downtime at zero.
- Result
- Zero-downtime OS migration with a 20-node scale-out, plus ELK dashboards for real-time data and logs.
- Stack
- Kafka, Flume, Hadoop, Spark, ELK Stack, Rocky Linux 8
MartDB generative AI data agent (GPT-4o)
KT
A GPT-4o PoC for KT that answers natural-language questions over the PostgreSQL MartDB with RAG and text-to-SQL, cutting query turnaround from hours to seconds.
- Problem
- Business stakeholders could not query MartDB without SQL, and analysts spent hours on manual queries.
- Design
- Connected PostgreSQL MartDB to an LLM on Azure AI. RAG plus text-to-SQL answers natural-language questions grounded in MartDB. Streamlit PoC interface.
- Rationale
- Chose text-to-SQL over pre-aggregation to keep answers current with the operational mart, and grounded generation with RAG to reduce hallucination on schema terms.
- Result
- Validated LLM querying over the operational mart. Query turnaround from hours to seconds.
- Stack
- Azure AI Studio, GPT-4o, PostgreSQL, Streamlit, Python
Airflow DAG batch scheduling
KT
Moved KT's Crontab-based Spark and stored-procedure batches to Airflow DAGs on Docker with explicit task dependencies and web-based monitoring.
- Problem
- Crontab-based batches had no dependency control or visibility.
- Design
- Analyzed Spark, stored-procedure, and Crontab jobs and moved them to Airflow DAGs with explicit task dependencies, on Docker, with web-based execution monitoring.
- Result
- Per-task failure tracking, web-based log and schedule inspection, and better maintainability on Docker.
- Stack
- Apache Airflow, Docker, Spark, PostgreSQL
Insurance system migration from on-premises to AWS
Corea Insurance Solution
Moved an insurer's core services from on-premises Docker hosts to AWS EC2 with security groups, least-privilege IAM, and EBS snapshot backups.
- Problem
- An insurer's core services ran on on-premises Docker hosts.
- Design
- Analyzed the full service topology and moved it to AWS EC2/IAM/EBS with security groups, least-privilege IAM, account permission design, and EBS snapshot backups.
- Rationale
- Kept the existing Docker packaging and moved to EC2 first to shorten the migration, leaving managed-service refactoring for a later phase.
- Result
- Migration completed with security and permissions in place; EBS snapshots established as the recovery baseline.
- Stack
- AWS EC2, IAM, EBS, Docker
iOS/Android QA automation
Hana Bank
Automated high-priority cases among Hana Bank's 3,300 manual app test scenarios with Appium and Pytest, running in parallel on three Android and three iOS devices.
- Problem
- Each banking app release carried 3,300 manual test scenarios.
- Design
- Automated high-priority cases with Appium and Pytest, running in parallel on three Android and three iOS devices.
- Result
- Reduced repeated regression effort and verified cross-platform compatibility.
- Stack
- Appium, Pytest, Python, iOS, Android, Nix-shell
Technical skills
| Cloud | AWS (EC2, IAM, EBS, VPC), Azure (App Service, Functions, AKS, Container Apps, Front Door, WAF, Key Vault, Entra ID, RBAC, Managed Applications, ARM), Docker, Kubernetes |
|---|---|
| Microsoft AI & Data | Microsoft Fabric, Azure Databricks, Azure OpenAI, Azure AI Foundry, Copilot Studio, Microsoft Purview |
| AI Engineering | RAG, embeddings & vector search, text-to-SQL, agentic workflows, prompt/context engineering, MLOps, LLMOps, Semantic Kernel, Claude |
| Data Engineering | PostgreSQL, Apache Iceberg, Parquet, Hadoop/HDFS, Spark, Kafka, Flume, Sqoop, Hive, Airflow, ELK Stack, lakehouse architecture |
| Languages / Stores | Python, SQL / PL-pgSQL, Java, C++, Shell, Oracle, Redis |
| Platform / OS | Rocky Linux 8, CentOS 7, Debian, Windows Server, macOS, HA design, Appium/Pytest automation |
| Business & Delivery | Solution architecture, technical presales, TCO optimization, SaaS / Managed Application packaging, marketplace GTM, ISV & partner enablement, Prosci change management |