At ResearchSpace, we maintain a firm commitment to the principle that infrastructure maintenance and technological advancement are equally critical to new feature development. While organizations often prioritize customer-facing enhancements, we recognize that strategic investment in our underlying technology architecture is fundamental to sustained product excellence, operational efficiency, and optimal user experience delivery.

We are currently executing a comprehensive platform modernization program, implementing a transition to a responsive, accessible framework leveraging React and TypeScript technologies. This systematic methodology for addressing technical debt ensures that our existing capabilities and future innovations benefit from contemporary development standards, improved maintainability, and compliance with modern accessibility requirements. Our commitment to accessibility is reflected in our documentation and the comprehensive self-assessment we've conducted to ensure our platform meets the highest standards of inclusive design.

A key element of this broader strategic initiative involved the migration of our established FlowJS codebase to TypeScript—a project that exemplifies how thoughtful planning can facilitate significant architectural transformations while preserving operational continuity. This migration also serves to lower the barrier for open source contributions, as TypeScript's widespread adoption in the development community makes it easier for external open-source contributors to understand and contribute to our codebase.

Background

Our development team had utilized FlowJS type annotations throughout our JavaScript infrastructure for the last five years. Type annotations explicitly annotate what types of data will be received and produced by functions in the code, making them more robust and easier to test. This implementation proved highly effective, facilitating early defect detection while maintaining confidence during refactoring processes and ensuring code predictability and comprehensive documentation. However, the broader development ecosystem has experienced a substantial shift toward TypeScript as the industry standard for statically-typed frontend development. As a result, TypeScript delivers superior library type definitions in addition to enhanced tooling capabilities and improved compatibility with contemporary development environments, and in particular AI-assisted coding platforms will have been trained primarily on TypeScript codebases at this point. This migration aligned naturally with our comprehensive modernization strategy.

Methodology

The primary operational constraint involved maintaining development velocity. With a rapidly evolving product, suspending feature development for an extended migration timeline was not strategically viable. As such, the approach we adopted was to leverage a fundamental technical insight: both FlowJS and TypeScript ultimately compile to JavaScript, with webpack managing type elimination during the build process. This capability enabled us to run both type systems concurrently throughout the migration period.

To preserve type safety across the hybrid codebase, we configured Flow to recognize TypeScript modules through library declaration files. This methodology enabled FlowJS components to import TypeScript modules while maintaining comprehensive type checking throughout the migration process. We progressively migrated the codebase from the leaves of the module dependency graph to the webpack entry points, creating a systematic wave of migration across the entire codebase. Each migrated module incorporated a corresponding FlowJS declaration file, ensuring continued type safety for unmigrated code utilizing these components, thereby maintaining a stable development environment throughout the transition period. This wave-based methodology enabled our development team to continue implementing new features in FlowJS while systematically converting the existing codebase.

Multiple technological tools accelerated our implementation timeline, including dependency analysis utilities for identifying migration candidates alongside AI-powered development environments that facilitated parallel processing capabilities. Our approach leveraged Anthropic's Claude model, focusing on developing sophisticated migration instructions through systematic feedback cycles rather than pursuing generalized automation. After approximately three days of methodical prompt engineering—incorporating detailed examples of FlowJS patterns with TypeScript equivalents and codebase-specific requirements—Claude achieved proficiency in migrating complete files with minimal human intervention. To maximize efficiency, we used git worktrees, enabling simultaneous migration processes across independent sections of the dependency graph, transforming a potentially months-long manual endeavor into a streamlined workflow that processed multiple files simultaneously. These optimization strategies collectively reduced our overall timeline by at least a month.

The result

This migration success validates our comprehensive technical philosophy: through systematic approaches to technical debt, modernization initiatives, plus platform evolution, we position our platform for sustained growth while ensuring our development organization possesses the necessary tools and technologies to deliver high-quality features efficiently. This investment in our technical infrastructure ultimately translates to enhanced developer productivity and expedited delivery of the innovations our users require.

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