Syntax Highlight Free and Open Source Desktop App CookApps CookApps Marketplace

Overview

Syntax Highlight (SourceCodeSyntaxHighlight) is the most advanced macOS Quick Look extension for source code files on macOS 12+. Powered internally by Andre Simon's Highlight engine, it supports Language Server Protocol (LSP) semantic enrichment, inline Git/VCS diff indicators, dozens of custom color schemes, plain-text file registration, and a live theme preview editor.

How It Works

Syntax Highlight operates through structured, deterministic execution stages:

Andre Simon Highlight Rendering Core: Formats hundreds of programming languages with customizable fonts, color themes, and semantic CSS styling inside Quick Look.

Language Server Protocol (LSP) Enrichment: Connects to installed local LSPs for deeper type-aware symbol highlighting inside previews.

Inline Git & VCS Diff Indicators: Queries local repository status to mark added, modified, and removed lines cleanly along the preview gutter.

Visual Settings & Theme Studio: Previews custom syntax themes live inside the companion configuration app with zero manual plist editing.

Syntax Highlight configuration app customizing themes and rendering rules

Syntax Highlight Quick Look view with VCS Git line change markers

Key Technical Features & Capabilities

Hundreds of Language Grammars: Colorizes C, Rust, TypeScript, Swift, Python, Go, Dockerfiles, XML, and obscure DSLs natively via Andre Simon Highlight.

LSP & Git VCS Gutter Indicators: Optionally hooks into installed Language Servers and local Git history to underline errors and mark added/modified lines right in Quick Look.

Live Settings & Theme Customizer: Adjust font family, font size, tab spacing, line numbers, word wrap, and dark/light palettes dynamically inside the companion app.

Unified CLI Converter: Converts source code directly to syntax-colored HTML or RTF outputs via its bundled command-line runner.

Architecture & Technology Stack

Primary Languages: Swift, Objective-C++, C++ (Highlight Library)

Frameworks & APIs: Apple QuickLookUI, AppKit, WebKit, LSP IPC Bridge

Build System: Xcode (Syntax Highlight.xcodeproj)

Supported Platforms: macOS 12.0+ (Universal Apple Silicon & Intel)

System Requirements

Specification	Minimum Requirement	Recommended Specification
Operating System	macOS 12.0+ (Universal Apple Silicon & Intel)	Latest stable release build
Processor Architecture	4-Core x86_64 or Apple Silicon M1	8-Core Apple Silicon / Core i7+
Memory (RAM)	4 GB Unified Memory	16 GB+ High-Speed RAM
Disk Space	1 GB free SSD storage	5 GB+ free SSD storage

Installation & Setup Guide

macOS Installation

bash

brew install --cask syntax-highlight

Or download Syntax.Highlight.zip from CookApps, drag Syntax Highlight.app into /Applications, launch once, and enable Quick Look Extension under System Settings.

Building from Source

bash

git clone --recursive https://github.com/sbarex/SourceCodeSyntaxHighlight.git
cd SourceCodeSyntaxHighlight
open "Syntax Highlight.xcodeproj"

How to Use & Workflow

Authorize Quick Look Extension: Open Syntax Highlight.app once and allow the plugin inside macOS Login Items & Extensions › Quick Look.

Pick Theme & Formats: Select preferred Light/Dark palettes and add any custom extensions in Format Management.

Preview Code Instantaneously: Press Spacebar on any source or config file in Finder (including extensionless Makefile or .env files).

Troubleshooting & Common Issues

Issue: macOS declines to open because binary isn't notarized by Apple.

*Cause*: Community release build triggers macOS Gatekeeper quarantine on direct download.

*Resolution*: Install via brew install --cask syntax-highlight or execute xattr -dr com.apple.quarantine "/Applications/Syntax Highlight.app".

Syntax Highlight

Overview

How It Works

Key Technical Features & Capabilities

Architecture & Technology Stack

System Requirements

Installation & Setup Guide

macOS Installation

Building from Source

How to Use & Workflow

Troubleshooting & Common Issues

How to Use & Getting Started

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