Amazing webmail+calendar+contact+files client.

A library that provides an embeddable, persistent key-value store for fast storage.

This code is a library that forms the core building block for a fast key-value server, especially suited for storing data on flash drives. It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF) and Space-Amplification-Factor (SAF). It has multi-threaded compactions, making it especially suitable for storing multiple terabytes of data in a single database.

Existing Gmail and Outlook MCP servers route queries through Google/Microsoft APIs. With stalwart-mcp, AI queries hit your Stalwart instance directly. Mail data never leaves your infrastructure; only the AI questions and answers go to the LLM provider.

A schema-driven command line tool for administering Stalwart Mail and Collaboration Server over its JMAP API.

The tool fetches the server's schema on first use and derives every command, validation rule, and rendered view from it. The same binary works against any compatible Stalwart deployment without recompilation.

Self-hosted JMAP webmail for Stalwart Mail Server. Mail, calendar, contacts, and files in one client.

Upbound built Crossplane to help organizations build their platforms like the cloud vendors build theirs—with control planes. Crossplane is an open source, CNCF project built on the foundation of Kubernetes to orchestrate anything. Encapsulate policies, permissions, and other guardrails behind a custom API layer to enable consumers, whether human users, automated workflows, or AI agents, to self-service without needing to become an infrastructure expert.

Crossplane builds on the class leading Kubernetes control plane, extending its battle hardened reliability and security features like Role Based Access Control (RBAC) to orchestrate everything - not just containers. By extending Kubernetes’ control model beyond containers, Crossplane enables a unified control layer for infrastructure. Because it shares a foundation with Kubernetes, Crossplane also integrates smoothly with the broader cloud-native ecosystem, allowing platforms to build automation and higher-level tooling without reinventing infrastructure fundamentals.

Uptime Kuma is an easy-to-use self-hosted monitoring tool.

One server for your email, calendars, contacts and shared files, with spam and phishing protection built in. Every standard protocol your clients already speak (JMAP, IMAP, POP3, SMTP, CalDAV, CardDAV and WebDAV) supported natively.

Running mail used to mean stitching together half a dozen separate components (an MTA, a message store, a spam filter, a calendar server, a contacts server, a file server) each with its own configuration quirks. Stalwart collapses all of that into one platform: fewer services to deploy, one configuration to learn, one place to look when something needs attention, and a smaller attack surface.

OPEN SOURCE EMAIL INFRASTRUCTURE for enterprises and high-volume senders

Because KumoMTA is Open Source, we don’t charge for the software — this work is sustained entirely through sponsorships. When you become a sponsor you not only gain access to support and services, you also help power the continued innovation and progress of today’s most advanced email solution.

All prices are per billion messages per year, with no limits on number of servers.

Higher volume senders can contact us for custom pricing.

More prosaically, you can use Sanoid to create, automatically thin, and monitor snapshots and pool health from a single eminently human-readable TOML config file at /etc/sanoid/sanoid.conf. (Sanoid also requires a "defaults" file located at /etc/sanoid/sanoid.defaults.conf, which is not user-editable.) A typical Sanoid system would have a single cron job but see INSTALL.md for more details:

The Fairphone (Gen. 6), reflashed by Catcrafts to run postmarketOS with the patches and IMS/VoLTE implementation Catcrafts maintains. All of that software is open source. You can download it and flash a Fairphone yourself, and you are welcome to. What you pay for here is the thing open source doesn't come with: real support.

postmarketOS develops free and open-source software to extend the life of consumer electronics.

By empowering people to have full control of their devices, we promote a healthier, more sustainable society.

Catcrafts makes accessible, open-source software and hardware for the benefit of everyone.

The goal: a real alternative to big tech that anyone can use, not just Linux nerds.

Self-hosted, semantically-connected personal knowledge base

A personal knowledge base that turns markdown notes into a semantically-connected, AI-augmented knowledge graph.

Atomic stores knowledge as atoms — markdown notes that are automatically chunked, embedded, tagged, and linked by semantic similarity. Your atoms can be synthesized into wiki articles, explored on a spatial canvas, and queried through an agentic chat interface.

In the spirit of openness, we are publishing our internal documentation for how we do open source at Google. We invite you to take a look behind the scenes at how we use, release, and support open source projects and communities.

Fighting air inequality through
open data.

OpenAQ is a nonprofit organization providing universal access to air quality data to empower a global community of changemakers to solve air inequality—the unequal access to clean air.

The Baochip-1x is an SoC with enhanced open source and security features. Fabricated in TSMC22ULL, it has a 350MHz Vexriscv RV32-IMAC CPU with Sv39 (virtual memory) support, along with 2MiB of integrated SRAM and 4MiB of integrated RRAM. RRAM is non-volatile memory analogous to FLASH.

The full part number is BAO1X2S4F-WA, but the part is referred to as the “Baochip-1x” or the “bao1x” interchangeably.

FlyDrive is a file storage library for Node.js. It provides a unified API to interact with the local file system and cloud storage solutions like S3, R2, and GCS.

Drive can be an excellent fit for applications that use cloud storage services to manage user-uploaded files. With Drive:

• You get a unified API for various storage services, including S3, R2, Digital Ocean spaces, GCS, and your local file system.
• Extensible API to add custom storage drivers.
• Unified exception handling.
• Baked-in security primitives to prevent common attacks like Path travesal.