Which one should I pick for a new project?

I can only provide technical analysis of these two libraries—the choice depends on your project's needs since they solve completely different problems.

ice-cube-ruby/ice_cube is a date recurrence library. Use it if you need to:

• Define recurring schedules (e.g., "every Friday the 13th in October")
• Query whether events occur on specific dates
• Generate occurrence lists for repeating events
• Model iCalendar-style recurrence rules

jekyll/jekyll is a static site generator. Use it if you need to:

• Build blogs, documentation sites, or static websites
• Convert Markdown/templates into HTML
• Manage collections, posts, and theming
• Deploy to GitHub Pages or similar platforms

These aren't alternatives to each other—they address entirely different domains. You might even use both together (e.g., a Jekyll site displaying event schedules generated with ice_cube).

Quality signals (from RepoPilot):

• ice_cube: Healthy across all use cases, 2468 stars, backed by comprehensive test coverage including YAML/iCal serialization and ActiveSupport integration [lib/ice_cube/parsers/ical_parser.rb:L1-L99]
• jekyll: A mature static site generator with extensive filtering, command infrastructure, and document processing

Recommendation: Pick based on your actual use case. If you're building a calendar/scheduling system, use ice_cube. If you're building a website, use jekyll.

FOLLOW_UPS:

• What does your project need to accomplish?
• Do you need recurring event scheduling or static site generation?
• Are you integrating with Rails or another framework?