ZECHAO JIN
Profile photo of Zechao Jin

ZECHAO JIN

zechao158@gmail.com| devzechao.com| github.com/zechao| linkedin.com/in/zechao-jin/| Palma de Mallorca, Spain

Profile

Backend Engineer with 8+ years building Golang microservices and distributed systems across fintech and travel, including APIs handling 7B+ requests/day. Strong in DDD, event-driven architecture, and using LLM workflows to automate engineering and business operations.

Skills

Programming: Golang, Python, JavaScript, C#, SQL
Frontend: Vue, HTML/CSS, React
Databases: Postgres, MySQL, Redis, Elasticsearch, SQLite
DevOps & Infrastructure: GitHub Actions, Docker, Kubernetes, AWS, Consul
Observability: Prometheus, Grafana, Kibana, Datadog
APIs & Messaging: REST, OpenAPI, GraphQL, gRPC, Protobuf, AWS SQS/SNS
Architecture & Practices: DDD, Clean Architecture, TDD, Event-Driven Systems, Microservices

Experience

BLP-Digital

📍 Remote

AI-driven platform automating ERP workflows

Senior Backend Engineer

Sep. 2025 - Present
  • Refactored the payment domain with a strategy-based design, replacing brittle switch routing and improving extensibility, documentation, and test coverage.
  • Built and shipped customer-facing backend features end-to-end in close collaboration with Product and Frontend teams.
  • Built an AI-assisted internal engineering assistant from Confluence, Jira, and historical PRs to answer documentation questions and help resolve low-complexity bugs and feature requests, shortening onboarding for new joiners.
Golang OpenAPI Docker K8S MySQL Protobuf GitHub Actions

AREX Markets and Bankable

📍 Remote

Lending platform for SMEs

Senior Backend Engineer

June 2021 - June 2025
  • Built and maintained event-driven microservices following DDD and clean architecture principles, using the transactional outbox pattern via AWS SQS/SNS to guarantee reliable event delivery and data consistency.
  • Decomposed a legacy Node.js monolith into domain-aligned Golang microservices, reducing P95 latency by 40% and enabling independent deployments.
  • Built automated risk evaluation and onboarding workflows with internal APIs, internal admin dashboards built in Vue, and third-party integrations for business data verification, public records checks, e-signatures, and contract generation, increasing onboarding speed by 3x.
  • Integrated LLM-powered document extraction to prefill onboarding forms, reducing manual data entry and improving onboarding speed and user experience.
  • Implemented file encryption and data anonymization for non-production environments to strengthen data security and protect sensitive information.
Golang Vue Protobuf Docker K8S AWS SQS/SNS AWS S3 Postgres Datadog

TravelgateX

📍 Palma de Mallorca

Global B2B marketplace for online travel services

Backend Engineer

Apr. 2018 - May. 2021
  • Built high-performance HotelX microservices in Golang serving 7B+ search requests per day across hotel search, booking, and static data APIs.
  • Implemented a configurable business-rules engine that let clients tailor search results, pricing preferences, and supplier data normalization.
  • Reduced API latency through in-memory caching, Redis tuning, and pprof profiling, lowering infrastructure costs.
  • Built the observability stack with Prometheus, Grafana, and Kibana, implemented alerting for latency, error rates, and health checks, and managed service configuration with Consul.
  • Traveled on-site to Ctrip (Trip.com) in China to provide hands-on API integration support, ensuring successful partner onboarding.

Integration Engineer

Aug. 2017 - Apr. 2018
  • Delivered 4 third-party supplier API integrations including Expedia, building and maintaining C# connectors to ensure reliable data exchange across the TravelgateX partner network.
Golang C# Elasticsearch Redis Consul Protobuf Prometheus GraphQL Docker Grafana

Education

Bachelor of Computer Science, Universitat de les Illes Balears (2013 - 2019)

Master of Data Science, Universitat Oberta de Catalunya (2020 - 2022)

Languages

Chinese: Native|Spanish: Fluent|English: Upper Intermediate