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Zhifan Chen SOFTWARE ENGINEER
CV

Engineering Engagements

Services & Consulting

I occasionally take on selected part-time engagements alongside my main work.

I partner with engineering teams, startups, and organizations that need senior software engineering depth, architecture modernization, and developer tooling improvements.

Consulting Services

01

Software Development & Modernization

Legacy codebases and tightly-coupled architectures slow delivery, introduce regressions, and resist new product features.

  • Incremental refactoring of legacy applications without downtime or complete rewrites
  • Full-stack TypeScript, React, and .NET architecture modernization
  • De-risking technical migrations by establishing automated end-to-end test coverage
02

Backend Features, APIs & Integrations

Products require resilient backend layers, secure authentication, or third-party service connections that scale predictably.

  • API design, development, and schema validation (REST, gRPC, event-driven webhooks)
  • Authentication and authorization architecture (OAuth2, OIDC, role-based access control)
  • Database modeling, migration safety, and transaction performance tuning
03

Developer Tooling & CI/CD Pipelines

Slow feedback loops, flaky continuous integration runs, and brittle manual deployment steps bottleneck engineering teams.

  • Automated CI/CD workflows with GitHub Actions, strict linting, and fast test execution
  • Internal developer CLI tools and automation scripts reducing repetitive tasks
  • Dependency management, artifact caching, and release automation
04

Nix & Reproducible Environments

Differences between developer laptops and production servers cause "works on my machine" bugs and onboarding friction.

  • Declarative Nix and Nix Flake environments ensuring identical developer workstations
  • Hermetic, reproducible build pipelines and lightweight deterministic container images
  • Self-hosted binary caching (e.g. Attic or Cachix) to speed up team build workflows
05

Technical Debugging & Root-Cause Investigation

Intermittent production anomalies, silent regressions, and elusive bugs resist superficial fixes and consume team bandwidth.

  • In-depth root-cause investigation across system layers from frontend to OS kernel
  • Diagnosing memory leaks, performance bottlenecks, and race conditions
  • Fixing upstream dependencies, build tools, or third-party open-source integrations

Working Model

Engagement Fit & Availability

To maintain engineering quality and deliver high-impact results, I accept a limited number of concurrent engagements that align with my technical focus:

✓ Strong Fit

  • • Asynchronous, written-first collaboration
  • • Technically deep problem solving and debugging
  • • Architecture, API design, and code modernization
  • • Developer tooling, Nix environments, and CI pipelines
  • • Bounded projects or advisory retainers (5–15 hrs/week)

✕ Out of Scope

  • • Round-the-clock on-call operational coverage or immediate incident SLA
  • • Synchronous full-day meeting schedules
  • • Unbounded open-ended staff augmentation without clear scope

Have an interesting engineering problem?

I occasionally take on selected part-time projects.

Discuss an engagement

Have an interesting engineering problem?

I occasionally take on selected part-time projects.

Let's talk