mailmate is a Ruby library and CLI for working with MailMate's on-disk storage and AppleScript surface. It includes a smart-mailbox filter engine (lexer/parser/evaluator over MailMate's filter language), readers for the binary header indexes, and CLI tools for searching, reading, modifying, and sending mail via MailMate. Requires macOS with MailMate installed. Some library pieces (parser, evaluator, fixture-driven tests) work on any platform; the integration pieces (AppleScript driver, filesystem readers) raise Mailmate::PlatformError on non-macOS hosts.

Serve markdown files from any directory with a clean web interface, syntax highlighting, YAML frontmatter support, and wiki-link resolution.

Provides a row-based object model and utility methods for creating, parsing, transforming, and exporting Markdown tables in Ruby.

システムが稼働する上で最初から必要なデータ（マスタデータ）を管理するツールです。

Parse MBOX files and export email data into CSV format

Meibo is a ruby library for OneRoster CSV Binding Japan Profile.

Fast and awesome tables, with pagination, sorting, filtering and custom views.

metanorma-utils provides utilities for the Metanorma stack

Sync transaction history from MoneyForward to YNAB.

Unofficial Ruby gem for Monogoto API. Monogoto is a IoT connectivity management platform

Toolkit for converting monolithic applications into modular, service-oriented architectures.

Codes (postal, istat, cadastrian, ...) about Italian subdivisions and municipalities in Italy [city, cities]

calculate coincidence(in %) between two music accounts

A tool for managing a TaskPaper file of project todos for the current directory. Easily create "next actions" to come back to, add tags and priorities, and notes. Add prompt hooks to display your next actions automatically when cd'ing into a directory.

Manage neetoDeploy apps with CLI

Scrapes NHK News Web (Easy) for the word frequency (core list) for Japanese language learners. Includes a CLI app and a scraper library.

A developer-friendly Ruby gem for interacting with NJTransit's API. Provides access to stations, routes, schedules, real-time arrivals, and more.

NKJ is a library for identifying JIS X 0213 characters.

not_pressed-core is the foundational engine behind NotPressed, a fully open-source, batteries-included CMS for Rails 8. It provides hierarchical pages, a block-based content editor, automatic navigation discovery from routes and view partials, a media library backed by Active Storage, a pluggable admin panel with configurable auth, and a content type registry — all built on Hotwire with zero external JS dependencies.

Mountable Rails engine for SQL charts, dashboards, and analytics.