Bailin Wong

Summary

Backend-focused engineer with 3+ years of professional experience delivering data-intensive systems in industrial/water-resource automation, now returning to full-time Java backend development — my degree field and long-term direction.

Outside of work I have independently designed, built, and shipped two production microservice applications (both live on app stores), covering API gateway, RPC, distributed transactions, caching, message queues, and object storage end-to-end. Comfortable owning a service from architecture through deployment and on-call troubleshooting.

Technical Skills

Languages & Core — Java 17, JavaScript, SQL; data structures & algorithms, networking, operating systems; basic JVM tuning and production troubleshooting

Frameworks — Spring Boot 3.x, Spring MVC, Spring Cloud Alibaba (Nacos, Dubbo, Sentinel, Gateway), Spring Security, MyBatis-Plus

Data — MySQL, PostgreSQL, SQL Server, Elasticsearch, Redis (multi-level caching, cache penetration/avalanche protection), Dameng DB

Messaging & Distributed Systems — RabbitMQ, Kafka; CAP, Raft, distributed IDs, distributed transactions; Outbox pattern for local-transaction/message consistency

Infrastructure & DevOps — Linux, Docker, Jenkins CI, Git, Maven/Gradle, Cloudflare R2 / S3-compatible storage

Frontend — HTML/CSS/JavaScript, React, Vue, Flutter (working knowledge), WeChat Mini Program (full release cycle)

Domain (Industrial Automation) — PLC programming (ABB, Hollysys, SUPCON, Nari-Autool), KingSCADA / Kingview, Modbus TCP/RTU, MCGS HMI, Kylin OS

English — Fluent spoken English; CET-6; read and work from English technical documentation daily. Currently preparing PTE Academic.

Experience

Talent Technology Co., Ltd. — Technical Engineer

Apr 2024 – May 2026 · Jiangsu, China

• Sole owner of the OA approval-workflow system for the Construction Management Center: 20+ workflows across web and mobile, from requirements through delivery.
• Owned database and data-processing work across 10+ water-resource informatization projects: schema design and historical-data ingestion/query code for water level, flow, electrical, and uplift-pressure telemetry (MySQL, SQL Server, Dameng).
• Built alarm queries, start/stop logs, and daily/monthly/annual reporting used for operational analysis by plant managers.
• When the SCADA vendor’s historian couldn’t support the required alarm analytics, designed independent business tables and query logic to deliver the functionality anyway.
• Handled device protocol parsing and data ingestion (Modbus TCP/RTU, RTU, DTU); ran field commissioning and acceptance testing.
• Deployed and adapted systems for domestic-stack environments (Kylin OS + Dameng DB), resolving JDBC/ODBC and compatibility issues.
• Led on-site incident investigation: network faults, database failures, system crashes, memory leaks, OPC communication failures.

Huai’an Kangaroo Mama Education Services — English Teacher

Sep 2022 – Sep 2023

• Taught primary through high-school English in small-group and 1:1 formats; wrote all courseware and assessment material.
• Communicated progress and study plans directly with parents. (This role is where my spoken English fluency was built.)

Projects

Sweet Home — Family Collaboration App, Backend (Personal) · Dec 2025 – Present

Live: https://www.sweethome.asia/ (also on Chinese app stores)

Stack: Spring Boot 3.5, Spring Cloud Alibaba (Nacos + Dubbo), Spring Cloud Gateway, MySQL, Redis, RabbitMQ, MyBatis-Plus, JWT

A vertical social app for families: group chat, family tree, location sharing (elderly/child safety), a shared activity feed, and an AI family assistant. Solo architecture and implementation.

• Designed a 6-service microservice architecture (auth / user / family / chat / location / feed) behind a gateway handling JWT auth and routing, with dual-key JWT separating the issuing service from verifying services. Inter-service calls over Dubbo RPC, deepest chain 3 hops.
• Real-time location + geofencing: members report position and battery continuously; custom safe zones trigger breach events published to RabbitMQ, decoupling alert detection and push delivery from the hot reporting path.
• Kinship-term inference engine: modeled the family as a graph (members as nodes, blood/marital ties as edges), BFS for shortest path, then rule-based reduction to the correct Chinese kinship term (e.g. Father.Son → “brother”). Unit-tested across direct, collateral, and in-law edge cases.
• Activity feed: text/image/video/voice posts, likes using ON DUPLICATE KEY UPDATE for atomic counting (avoiding check-then-act races), and paginated reads that batch-fetch (IN + group aggregation) to eliminate N+1 queries.
• WebSocket chat that scales horizontally: Redis Pub/Sub broadcasts only message IDs across instances; each node pulls and assembles per-recipient views on demand, so connections can live on any node.
• Rate-limited the highest-traffic endpoint (location reporting) with Redis + Lua atomic scripts and Sentinel; cache-aside Redis layer on family/user lookups.
• Uniform Result<T> response envelope, BusinessException + global exception handler, and globally configured logical deletes.

Liminality — Anomalous-Events Archive App, Backend (Personal) · Apr 2025 – Present

Live: https://www.liminality.asia/ (also on Chinese app stores)

Stack: Java 17, Spring Boot 3.2.4, Spring Cloud Gateway, Nacos, OpenFeign, MyBatis-Plus, PostgreSQL, Redis, JWT, S3 SDK (Cloudflare R2)

A community app for cataloguing paranormal, anomalous, and UFO reports. Solo-built microservice backend: gateway, auth, user, and archive (incl. image storage) services plus shared common/api libraries, with Nacos for discovery and config.

• Centralized authentication in a gateway filter (AuthGlobalFilter) with an AntPathMatcher whitelist; validated JWTs are exchanged for a user-ID header, so downstream services never touch raw tokens. Downstream interceptors bind that header to a ThreadLocal, keeping auth logic out of business code entirely.
• Cross-service calls via OpenFeign + Nacos discovery, with all client interfaces isolated in a dedicated api module to keep transport concerns out of business modules.
• Implemented WeChat Mini Program login: exchanged code for openid via code2session, silently registered new users (avatar, nickname), and issued a first-party JWT — full authorize → identify → session flow.
• Stored semi-structured archive data (character-relationship graphs, timelines, evidence chains) as PostgreSQL JSONB via JacksonTypeHandler, keeping schema flexibility without giving up type safety.
• Built a reusable pagination component (PageQuery/PageResult) with configurable sort field/direction and Bean Validation on inputs.
• Image upload to Cloudflare R2 (S3-compatible): server-side size (≤1MB) and MIME validation, object keys generated by date + UUID.
• Generic IEnum-based enum base class unifying enum↔integer mapping for archive type, status, and visibility.

Jiaoling Pumping Station Assistant — Water-Utility Mobile Backend · Oct 2023 – Mar 2024

Stack: Spring Boot, MySQL, Redis, Modbus TCP

Remote monitoring and historical-data platform for irrigation/drainage pumping stations.

• Built device control and telemetry acquisition on Spring Boot + Modbus TCP.
• Modeled device lifecycle as an explicit state machine (running / fault / interlock / protection) to tame complex industrial control logic.
• Solved blocking under high-frequency device polling with a thread pool + queue buffer.
• Cut historical-query latency by 60%+ through MySQL index and partitioning redesign.
• Added Redis as a device-state cache layer to relieve write pressure on MySQL.

Education

B.Sc., Computer Science and Technology — Jingjiang College, Jiangsu University · Sep 2017 – Jun 2021

Awards: University First-Class Scholarship (×2), Second-Class Scholarship (×1), National Encouragement Scholarship, Outstanding Graduate, Model Student.

Certifications

• Software Designer, Intermediate (MIIT China) — May 2024
• Digital Economy (Electronic Information) Assistant Engineer — Nov 2023
• CET-6 (College English Test Band 6) — 2022