Caxton

Caxton is a native large file editor for macOS.

Specifically designed to handle production logs, database export files, extremely large CSV and JSON exports, and crash reports that are difficult to open with ordinary text editors. It employs memory-mapped I/O, a piece-table document model, and hierarchical row indexing, capable of fully opening and indexing files up to 10GB in size and exceeding 80 million lines, while rendering only the content of the current viewport, allowing for smooth scrolling even in extremely long single-line compressed files. The software offers log follow mode, full-text search, regular expression matching, batch replacement, multi-condition filtering, preservation of original line numbers, and the ability to open large files in segments; CSV mode supports automatic delimiter recognition, frozen headers, type inference, sorting of millions of rows and columns, cell editing, column splitting, merging, extraction, and deduplication. Built on AppKit and Swift, Caxton does not rely on Electron or web views, supports dark mode, tabs, native file dialogs, system services, and printing functionality. Files remain locally by default, without uploading, cloud processing, or telemetry.