Spekter

Overview

Spekter is a file comparison program, available on Linux.

Features described in its Flathub listing: tabbed interface.

Overview written by LicitPro from the documentation published by the authors and the cited sources; we have not tried the resource ourselves.

At a glance

All of Spekter is free: no feature is locked behind a paid plan, and its code is open.

Its licence (MIT) is a permissive open source licence: use, modification and redistribution are allowed, including in commercial projects.

About

Visual GUI tool for recursive directory and file comparison. Side-by-side and unified diff views with synchronized scrolling, inline character-level highlighting, Meld-style Bezier gutter connectors and a tabbed interface. It follows your light or dark system theme. Binary files are detected and reported with sizes rather than rendered as garbled text. Spekter detects when JSON or JSONL files differ only in element ordering, and applies hunk-slider postprocessing so an inserted object in a JSON array is marked as one whole object. Code and data files are syntax coloured, with grammars for a lot of languages built in and more available as plugins: a plugin is just a folder of Sublime Text grammar files, with no code to install. Colouring is instant. Large files stay responsive: a file's text appears instantly while its diff is computed on a background thread, computed diffs are cached, and the changed files are prefetched as you browse, so opening or revisiting them feels immediate even at a million lines. Ignored entries (.git, node_modules, editor swap files and the like) are skipped but listed as dimmed stubs rather than silently erased, and the rules go both ways: expand an ignored directory or open an ignored file to compare it anyway, or right-click any entry to ignore it yourself. These choices are remembered per directory pair. An instant, keyboard-driven alternative to Meld and diff for comparing folders and code.

Description from Flathub — AppStream (Flathub)