KillBill
Kill Bill handles the complete subscription billing lifecycle from plan definition through invoice generation to payment collection across any gateway, with 15 years of Fortune 500 production use and 5,600+ GitHub stars behind it. Plans, trials, add-ons, and pricing tiers live in a versioned XML catalog that propagates changes without code deploys. The multi-phase subscription engine manages trial periods, promotional discounts, evergreen billing, usage-based metering, and hybrid pricing models with automatic proration on plan upgrades and downgrades. Automated invoice generation calculates charges, applies credits and adjustments, and triggers payment collection through pluggable gateways including Stripe, Adyen, Braintree, PayPal, and CyberSource. The Java plugin framework extends every billing domain with custom logic for tax calculation via Avalara AvaTax or Vertex, fraud detection through Accertify or Feedzai, and ERP integration without modifying the core. The Kaui admin dashboard gives finance and operations teams account management, subscription controls, invoice views, payment configuration, billing timeline visualization, MRR tracking, advanced search, and full audit history with object-level change tracking. Multi-tenancy isolates billing data across thousands of brands with tenant-specific catalogs, payment configs, and RBAC policies. REST APIs expose every operation with webhook notifications for downstream integration. Deploys via Docker Compose on MySQL or PostgreSQL. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.
XWiki
With over 140,000 code commits, 1,200+ GitHub stars, and continuous development since 2004 spanning more than two decades of active maintenance through version 18.6.0 released in July 2026, XWiki operates as a second-generation wiki platform that goes beyond static pages by enabling teams to build custom collaborative applications directly inside wiki pages using structured data forms and in-page scripting. The Java backend runs on Apache Tomcat with PostgreSQL, MySQL, or Oracle database storage, serving a responsive web interface with a WYSIWYG editor featuring real-time collaborative editing, link and macro editors, user mentions, inline comments, annotations, and complete version history with diff comparison. The App Within Minutes extension lets non-developers create custom data-driven applications using drag-and-drop form builders that generate filterable live tables for structured data browsing without writing code. Over 900 extensions from the built-in Extension Manager add functionality including blogs, task trackers, forums, diagram editors, and Confluence migration tools. Enterprise integration features include LDAP and Active Directory authentication, SAML and OIDC single sign-on, fine-grained per-page and per-space permissions with nested page hierarchies, and multi-wiki support for hosting multiple independent wikis from a single installation. The RESTful API provides programmatic access to pages, spaces, objects, attachments, and properties with XML and JSON representations. Office document import converts Word and Excel files directly into wiki pages while PDF export generates formatted documents from wiki content. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. LGPL-2.1 licensed.
Pumpkin
Why keep a Java runtime on the server just to host Minecraft, when Pumpkin runs from a single native executable and lets Java and Bedrock players share a world? Java Edition clients join on port 25565 and Bedrock clients on 19132, although Bedrock support is still marked work in progress. Builds exist for Windows, Linux, macOS, and Android. On launch, the console reports the worlds loaded and the server ready within milliseconds. Plugins are sandboxed WebAssembly modules that raise console permission prompts and pass signature checks, and authors can write them in Rust, Kotlin, Python, Go, C#, C/C++, D, Zig, or TypeScript. The ppm package manager searches and installs community plugins from the Pumpkin Market, and PatchBukkit loads some Bukkit and Paper plugins, with expected gaps. One pumpkin.toml file holds ports, MOTD, view distance, whitelist, authentication, compression, PvP, chat, resource packs, and world options, while chunks save in Anvil, Linear, or the native Pump format. Velocity and BungeeCord forwarding fit proxy networks, and the Query protocol plus Minecraft Server Management Protocol cover monitoring and remote administration. A public parity tracker lists every vanilla block, entity, item, and command as implemented, partial, or planned, so gaps are easy to spot before a world moves. Today it suits private survival worlds, test servers, and plugin development. It is early software, so the project advises backups. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-3.0 licensed.
Verdaccio
Private npm packages without shipping code to the public registry or paying for npm Enterprise: Verdaccio is the standard lightweight, zero-config private registry and caching proxy. It runs as a single Node.js process with its own tiny embedded database; no external database is required to start. Point npm, yarn, or pnpm at it and everything behaves as expected: install, publish, unpublish, dist-tags, and deprecation all work against the standard npm endpoints. The uplink system is where it earns its keep: packages not found locally are fetched from configured upstreams (npmjs.org, yarn, JFrog, Nexus, or another Verdaccio), cached as tarballs, and served locally thereafter - cutting CI latency and surviving registry outages. Multiple uplinks chain for failover, and per-package glob patterns in config.yaml route scopes to specific upstreams while controlling access, publish, and unpublish rights per group. You can even override a public package by publishing a patched version under the same name locally. A plugin architecture swaps in auth backends (htpasswd default, LDAP and others available), storage drivers (S3, Google Cloud Storage), middleware routes, and metadata filters. With official Docker images and a Kubernetes Helm chart, it slots into any pipeline in minutes.