Josh focused on enhancing code completion workflows in Swift by developing targeted features across the Wilfred/sourcekit-lsp and swiftlang/swift-syntax repositories. He introduced a ClosureCompletionFormat class and refactored placeholder translation logic to improve nested placeholder handling and LSP snippet compatibility, addressing common pain points in closure-heavy code. In swiftlang/swift-syntax, Josh designed a customizable API for closure placeholder expansion, enabling multi-line trailing closures and flexible placeholder wrapping. His work leveraged skills in API design, syntax parsing, and code refactoring, resulting in more consistent and productive code completion experiences for Swift developers, with a clear emphasis on cross-repository consistency and maintainability.