JuffEd is described as 'free, cross-platform text editor for programmers and advanced users. It has syntax highlighting for many languages, code folding, find/replace using plain text and regexps, code completion, multiple charsets and many other useful features' and is a Text Editor in the Development category. There are more than 25 alternatives to JuffEd for a variety of platforms, including Windows, Linux, Mac, BSD and Chrome OS. The best alternative is Visual Studio Code, which is free. Other great apps like JuffEd are Atom (Free, Open Source), Vim (Free, Open Source), Kate (Free, Open Source) and Bluefish Editor (Free, Open Source).
Visual Studio Code is more than just a code editor, it provides the tools and extensions to compile, debug, compare, refactor, and even manage code repositories all within a highly-customised development environment.
The Kate project develops two main products: KatePart, the advanced editor component which is used in numerous KDE applications requiring a text editing component, and Kate, a MDI text editor application.
Bluefish is a powerful editor targeted towards programmers and webdesigners, with many options to write websites, scripts and programming code. Bluefish supports many programming and markup languages, and it focuses on editing dynamic and interactive websites.
CudaText is a cross-platform text editor, written in Lazarus. It starts quite fast (0.5 sec with ~30 plugins on CPU Intel Core i3 3Hz). It is extensible by Python add-ons (plugins, linters, code tree parsers, external tools).
TextMate brings Apple's approach to operating systems into the world of text editors. By bridging UNIX underpinnings and GUI, TextMate cherry-picks the best of both worlds to the benefit of expert scripters and novice users alike.