Senior JavaScript / TypeScript Developer for Real Estate Feasibility & Computational Geometry

Parcel seeks a Senior JavaScript and TypeScript developer to scale an existing real estate feasibility tool by decoupling the core calculation engine from the UI and implementing automated testing. The initial geographic focus is San Diego, California, with remote work available.

Responsibilities

• Review the existing codebase
• Refactor calculation logic into a standalone deterministic engine
• Separate the core calculation engine from the UI
• Preserve existing application behavior
• Create automated parity and regression tests
• Create tests to verify that the refactored engine maintains the existing results
• Build automated scenario testing
• Improve code architecture and maintainability
• Prepare the system for future AI-assisted analysis and testing
• Provide an architecture assessment
• Recommend a refactoring plan

Requirements

• Strong JavaScript / TypeScript
• Node.js
• Software architecture
• Computational geometry
• Algorithm development
• Automated and regression testing
• Property-based testing or simulation
• GIS / geospatial development is a plus
• PropTech or real estate technology is a plus
• Experience integrating Claude or other LLM APIs is a plus
• Understanding the importance of keeping core calculations deterministic and auditable while using AI as a separate analysis layer

Technologies

• HTML
• JavaScript
• TypeScript
• Node.js
• Claude
• LLM APIs

Benefits

• Flexible schedule

Initial Scope

• Review and understand the existing prototype
• Refactor calculation logic into a standalone deterministic engine
• Preserve existing application behavior
• Create automated parity and regression tests
• Build automated scenario testing
• Improve code architecture and maintainability
• Prepare the system for future AI-assisted analysis and testing

Ideal Experience

• Strong JavaScript / TypeScript
• Node.js
• Software architecture
• Computational geometry
• Algorithm development
• Automated and regression testing
• Property-based testing or simulation
• GIS / geospatial development is a plus
• PropTech or real estate technology is a plus
• Experience integrating Claude or other LLM APIs is a plus

When applying

• Have you built a rules-based, simulation, optimization, or computational geometry engine before?
• Have you worked with automated scenario or property-based testing?
• Do you have experience with GIS, PropTech, real estate, or parcel data?
• Have you integrated Claude or other LLMs into production applications?
• Please provide examples of the most technically relevant projects you have worked on.