MarkdownPreview
A Quick Look extension that renders Markdown files in Finder — just press Space. GitHub-style output with syntax highlighting, math, and dark mode.
YAMLPreview
A Quick Look extension for .yml / .yaml files. Preview configuration and data files with clean syntax highlighting, right from Finder.
SweepBar
A menu-bar utility for safe, scan-first macOS cleanup. Review caches, logs, and Xcode & developer junk in a checklist — then reclaim the space. Nothing is removed without your confirmation.
XcodeCleaner
Reclaim gigabytes of disk space from Xcode caches — DerivedData, simulators, device‑support files, Swift Package caches, and more. Scan, review, and clean with one click.
iOS IPA Install
Install iOS .ipa packages onto development devices straight from Finder — right-click an IPA, pick the connected device, and install via Apple’s cfgutil. Automatic device detection included.
GridNavigation
A high-performance, cross-platform SwiftUI grid-navigation library with full keyboard support. For developers building grid-based interfaces.
iDigits
A math puzzle game for iPhone and iPad — combine numbers and operators to hit the target. Quick, addictive mental-math workouts.
OceanTides
Tide predictions for macOS — daily and weekly tide charts, moon phases, sunrise and sunset times, for thousands of stations worldwide. Includes a desktop widget.
ClaudeWatcher
Your Claude usage, live in the menu bar — 5-hour and weekly limit gauges with reset times, today’s message and token counts, and your credit balance. Reuses your existing Claude Code login; nothing leaves your Mac.
Preview Markdown & YAML in Finder, for free
MarkdownPreview is a lightweight macOS Quick Look extension for previewing Markdown files.
Select any .md, .markdown, .mdown, or .mkd file in Finder and press
the Space bar — you’ll see a fully rendered preview with headings, tables, code blocks
(with syntax highlighting), math typesetting via KaTeX, and automatic light/dark mode.
It’s sandboxed, works entirely offline, and auto-updates through Sparkle.
The app is signed with a Developer ID and notarized by Apple — no Gatekeeper warnings.
YAMLPreview does the same for .yml and .yaml files — a format
macOS has no built-in preview for. It adds syntax highlighting and an optional line-number gutter,
using the same sandboxed, notarized architecture as MarkdownPreview.
OceanTides brings tide predictions, moon phases, and sunrise/sunset times to your Mac — daily and weekly charts for thousands of stations worldwide, plus a desktop widget. Developer ID signed, notarized, and auto‑updated via Sparkle.
XcodeCleaner reclaims disk space from Xcode's accumulated junk — DerivedData, device‑support symbols, simulators, archives, Swift Package caches, and expired provisioning profiles. Scan, review what you want to remove, and clean with one click. Developer ID signed, notarized, and auto‑updated via Sparkle.
All are part of a small suite of free macOS & iOS tools by
Julien Nicolas, built in Swift and SwiftUI.
Also available: OceanTides
(tide predictions for macOS),
SweepBar
(a menu-bar macOS cleanup utility),
iOS IPA Install
(install iOS .ipa files to devices via cfgutil),
GridNavigation
(a cross-platform SwiftUI grid-navigation library),
ClaudeWatcher
(a menu-bar monitor for your Claude usage) and
iDigits
(a math puzzle game on the iOS App Store).