Open to opportunities

Jay Ni

@jayni1

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Senior full stack engineer delivering scalable Ruby and cloud platforms that solve complex business problems.

United States

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What I'm looking for

I’m looking for a team that values clean, maintainable code and scalable systems—where I can lead backend/API work and cloud-powered async processing, improve reliability, and ship measurable business impact.

I’m a Senior Full Stack Engineer with 10+ years of experience building scalable, cloud-based applications, with a strong focus on Ruby and Ruby on Rails. I’ve designed and delivered backend systems, APIs, and data-driven platforms across financial and SaaS domains, always prioritizing clean, maintainable code and reliable delivery.

Most recently at Fidelity Investments, I built a multi-tenant investment operations platform, improved transaction processing latency by 30%, and strengthened automation with Sidekiq/Redis background workflows and secure JWT-based integrations. I also create operational tools with Hotwire (Turbo + Stimulus), and have led architecture discussions while mentoring junior engineers—bringing microservices, asynchronous processing, and AWS deployments together to produce real business impact.

Experience

Work history, roles, and key accomplishments

Current

Senior Full Stack Engineer

Current

Fidelity Investments

Jan 2024 - Present (2 years 4 months)

Built a multi-tenant investment operations platform in Ruby on Rails, designing domain models and REST APIs for investor onboarding, capital calls, and reporting workflows. Reduced transaction processing latency by 30% using Sidekiq/Redis job batching and retries, and improved data ingestion throughput by ~40% with C# microservices.

Ruby on Rails REST APIs RSpec Capybara Sidekiq Redis JWT Hotwire (Turbo + Stimulus)Microservices C# .NET

Software Engineer

Indiana Farm Bureau Insurance

Apr 2021 - Jan 2024 (2 years 9 months)

Developed a policy management platform in Ruby on Rails for policy lifecycle, billing cycles, and customer account interactions. Reduced production incidents by ~25% by improving validation and background-job error handling, implemented graphql-ruby APIs, and improved report generation time by ~35% through optimized batch processing and database queries.

Ruby on Rails RSpec Sidekiq GraphQL Ruby CI CD Query Optimization

Software Development Engineer

Viavi Solutions

Jan 2016 - Apr 2021 (5 years 3 months)

Built a customer onboarding and account management system using Ruby (Sinatra) and lightweight APIs for registration, profile management, and verification workflows. Improved onboarding completion by ~20%, reduced query response time by ~30% with PostgreSQL indexing/query optimization, and enabled asynchronous communication via RabbitMQ.

JavaScript jQuery PostgreSQL RabbitMQ AWS Elastic Beanstalk Responsive UI Indexing Asynchronous Communication

Software Engineer

Diligent Software Systems Inc.

Aug 2016 - Nov 2016 (3 months)

Implemented backend features with Ruby on Rails, building CRUD operations and RESTful APIs while securing endpoints with Devise. Improved page load time by 20% through optimized server-side rendering and reduced authentication-related issues by 15% by enhancing validation and session handling.

Ruby on Rails REST APIs Devise RSpec Authentication Authorization Server Side Rendering

Web Developer

IUPUI Multicultural Center

May 2015 - Dec 2015 (7 months)

Built responsive marketing and informational web pages using HTML, CSS, and JavaScript, creating interactive UI components with jQuery. Improved responsiveness across 3+ device types and reduced UI bugs reported by users by 20% through cross-browser testing, debugging, and iterative refinements.

HTML5 CSS3 JavaScript jQuery AJAX Responsive Web Design Cross Browser Testing Media Queries