Backend Engineer
Giantforest Solutions Co., Ltd.
Apr 2022 – Present
Lead backend architecture and legacy modernization for the group's listed companies, managing two engineers.
- Delivered a visitor access platform integrated with existing door controllers, serving 20+ tenants.
- Migrated two legacy applications spanning 5+ business systems to Spring Boot with zero downtime.
- Integrated SSO with Keycloak (OIDC) and back-channel logout, with sessions centralized in Redis.
- Built the internal framework: parent POM and BOM plus shared Spring Boot starters.
- Introduced Liquibase for schema versioning, making changes traceable and reviewable.
- Adopted Testcontainers for integration tests, running real dependencies in containers instead of mocks.
- Optimized GitLab CI runners, cutting build time by 30% and bandwidth by 75%.
- Mentored junior engineers and set team workflow standards through workshops and documentation.