01
Let the AI assistant really know how to write Word, Excel and PPT
⭐ Total stars 31976 ｜ Language C# ｜ Created on 2026-03-15
OfficeCLI claims to be “the world’s first Office suite specifically built for AI Agents” – it allows any coding agent to read, write, edit and automate Word, Excel, and PowerPoint files with one line of commands, without the need to install Office on the machine and without unnecessary dependencies.
Its most ingenious trick is its built-in HTML rendering engine: it can render .docx / .xlsx / .pptx into HTML or PNG images with high fidelity, which is equivalent to installing “eyes” on the AI, allowing the agent to complete the closed loop of “rendering → viewing → correction” instead of blindly changing the file format.
According to the official statement, the business-style, technology-style, and space-style PPTs in README, as well as papers, reports, and budget tables are all generated by AI Agent using it, without templates or manual editing. It is compatible with mainstream agents such as Claude Code, Codex, Cursor, etc. It can be installed automatically by pasting a piece of SKILL.md into the conversation. For developers who want to open up office document capabilities to AI, or people who want to use natural language to generate Office files, this is currently the most trouble-free open source solution.
OfficeCLI
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02
An open source optimization tool that slims down and speeds up Windows with one click
⭐ Total stars 10430 ｜ Language C# ｜ Created on 2025-10-31
optimizerDuck is a free and open source Windows optimization tool that focuses on three things: performance, privacy and simplicity. It uses WinUI to create an interface close to the native Windows 11, and packages common optimizations such as removing bloat, turning off telemetry, and adjusting system options into visual switches.
It solves the pain point of “wanting to optimize but being afraid of problems”: all changes are clearly listed on the interface, and users can choose one by one, instead of pasting a registry script with unknown origin, so they know what has been changed and what can be restored.
The project is updated diligently, supports more than ten languages, and also provides official website documentation and Discord community. It is suitable for old Windows users who have just reinstalled the system or are slowed down by various pre-installed software; it is recommended to understand the meaning of each option before taking action to avoid accidentally turning off services that affect daily use.
optimizerDuck
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03
Microsoft officially packages .NET development experience into AI programming assistant
⭐ Total stars 5623 ｜ Language C# ｜ Created on 2026-02-03
This is a set of “intelligent skills” warehouse maintained by the .NET team personally. The goal is very straightforward: to make the AI coding assistant truly understand .NET and C#. It follows the Agent Skills standard. After installation, the agent will automatically call the corresponding skills when you put forward relevant requirements.
The content coverage is quite wide, split by plug-ins: not only general .NET development skills and C# language server integration, but also ASP.NET Core, Blazor, WinForms, MAUI, Entity Framework, NuGet package management, MSBuild build diagnosis, project upgrade migration, test framework migration, as well as AI/ML, RAG, and MCP workflow in .NET.
It is compatible with mainstream hosts such as GitHub Copilot custom agents, and also provides a “skill value dashboard” that uses token consumption, time consumption, activation rate and failure rate to quantify the actual effect of each skill. For .NET developers, this is equivalent to directly precipitating official best practices into AI callable tools, rather than relying on prompt words to try their luck every time.
.NET Agent Skills
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04
Change Pokémon saves on your Android phone and move across generations
⭐ Total Stars 831 ｜ Language C# ｜ Created on 2026-07-17
PKForge is a Pokémon archive editor and “bank” running on Android. It is built based on the well-known project PKHeX.Core and implemented using MAUI + SkiaSharp. It is specially adapted for dual-screen handheld consoles such as AYN Thor.
Its core gameplay is to put the entire team and box in your hands: you can modify individual values, effort values, moves, personality, characteristics, carrying props, Taijing attributes, intimacy, etc. There is also real-time legality check during editing; the built-in Auto Legality Mod allows “one-click legalization” to be completed completely offline on the device.
What’s even more interesting is its cross-generation Bank, which can move Pokémon from the first generation to the ninth generation and back. It also provides a centralized collection similar to Pokémon Home, 1,025 full illustrations for tracking, and automatic generation of living illustrations. All changes will be previewed and legalized first, and then written into the archive after confirmation. The official website clearly reminds: Only the Release in this warehouse is the official channel, and the downloads from other sites are fakes. Remember to back up the archive before using it.
PKForge
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05
Use C# to write a local game server and run it yourself to study network protocols.
⭐ Total stars 765 ｜ Language C# ｜ Created on 2026-04-20
MikuSB is a game server simulator written in C#/.NET 9. It performs local reproduction of the client protocol of a certain two-dimensional dungeon-themed game. The goal is to study the protocol and network behavior. It puts SdkServer, GameServer and an optional local HTTP/HTTPS proxy all into the same .NET application.
The structure is divided quite clearly: SdkServer is responsible for returning server lists, version queries and other HTTP interfaces; GameServer receives TCP game connections and processes specific data packets; Proxy will listen to 127.0.0.1:8888 when enabled and redirect relevant domain names to the local server; Proto centrally manages protobuf definitions.
Judging from the function list, basic processes such as login, character/equipment/skin loading, lobby state saving, and audio game chapter entrance have been completed, while combat, card drawing, tasks, multiplayer, etc. are still on the way. The author repeatedly emphasizes that this is “for research and testing purposes in a local environment” and is not intended for unauthorized access or commercial use. The project itself does not contain any game materials or binaries; the license is MIT and requires the .NET 10 SDK to build. Suitable for technical researchers interested in game server protocol reversal and network programming.
MikuSB
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06
A .NET 10 microservice architecture example that you can copy directly
⭐ Total stars 751 ｜ Language C# ｜ Created on 2026-09-05
booking-microservices is a ticket booking system, but its real value lies in “showing all the things that production-level microservices should have”: based on .NET 10, using vertical slicing architecture, DDD, CQRS, and introducing event sourcing (EventStoreDB) on the writing side of the booking service.
Its technology stack is almost a modern .NET back-end map: Wolverine + RabbitMQ is event-driven, with persistent inbox (idempotent, exactly once) and outbox (at least once); synchronous calls between services are made through gRPC; writing models use PostgreSQL, and reading models use MongoDB; identity authentication is handed over to IdentityServer, and gateways use YARP; observability is OpenTelemetry + Jaeger + Prometheus + Grafana + Serilog/Kibana A dragon.
What’s even more rare is that it also provides all the orchestration methods – Docker Compose, Kubernetes (Nginx Ingress, cert-manager) and .NET Aspire are all supported, and it is also equipped with unit, integration, end-to-end and contract testing (NSubstitute, Testcontainers, PactNet). For developers who are building microservices or want to systematically learn the .NET distributed architecture, this is a complete template that can be directly copied.
Booking Microservices
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07
No graphics library is needed, pure C# runs the 3D engine on the command line
⭐ Total stars 715 ｜ Language C# ｜ Created on 2026-06-06
Neo 3D is a minimalist 3D engine, entirely written in C#, and runs entirely on the system command line. It deliberately does not use any third-party graphics libraries, from custom vector operations, ray casting/ray tracing to network code, everything is completed on the CPU.
The rendering effect is achieved by a set of character gradient maps – mapping brightness to " .:!/r(l1Z4H9W8$@" With this string of characters, you can draw a sphere and .obj model with light and shadow in the terminal. It has also made many engineering optimizations: bounding ball prediction, distance attenuation, Lambert diffuse reflection, shadow light, using Parallel.For multi-threading to amortize pixel calculations, frame buffering and same-color batch output to reduce console calls.
Even the input system in the project is self-written, using User32.dll for Windows and X11 for Linux. It also comes with a custom client-server module based on TCP, which can enable online and real-time chatting. It was originally created for a YouTube demonstration video, and later plans were made to use Vulkan to move heavy computing to the GPU. This is a very fun practice project for those who are new to graphics or want to understand the principles of light tracing in a restricted environment.
Neo 3D
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08
Hold down a key and drag the file to the icon to complete the conversion
⭐ Total stars 712 ｜ Language C# ｜ Created on 2026-09-29
Filee is a free and open source file converter with a unique interaction method: hold down Ctrl (Option on macOS) and drag the file, and a donut-shaped format menu will pop up at the cursor. Drop the file into the desired target format and the conversion will be completed without opening any windows.
It claims to support more than 180 formats, covering pictures, PDF, Word, Excel, PowerPoint, HWP/HWPX, e-books, compressed packages, fonts and CAD, etc., and does not rely on Office, Hancom Office or LibreOffice; for heavy tasks such as video and audio, optional engines such as FFmpeg can be downloaded on demand.
Its biggest feature is “localization” – files are not uploaded, and are processed completely offline. The results are stored next to the original files, and privacy is controllable. Developed based on Avalonia, Windows 10/11 is the main platform, macOS and Linux are preview versions; MIT license supports command line and silent updates (the installation package will verify SHA-256). It is suitable for users who often have a bunch of formats in their hands that need to be converted, but don’t want to install a bunch of professional software.
Fillet
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09
Manage audiobooks and e-books in the same self-built library
⭐ Total stars 674 ｜ Language C# ｜ Created on 2026-06-29
Chapterr is a fork derived from the famous book management tool Readarr, with a clear goal: to manage both audiobook and e-book libraries in one instance, rather than splitting them into two systems. It’s particularly good at handling metadata that many general-purpose media managers don’t care about – such as audiobook-specific “reader”, multiple versions (audio + electronic version of the same book) and publisher information.
Functionally, it can identify and organize M4B, chaptered MP3 and multi-file audiobooks, and can optionally synthesize MP3 audiobooks into a single chaptered M4B. It is equipped with standard integration for *arr family downloaders and indexers, automatic upgrades, metadata configuration files filtered by language and customizable renaming rules. File naming supports audiobook-specific tokens.
It should be reminded that the author clearly positions it as Beta software and currently only supports Docker deployment. He also clearly states that it has no affiliation with the Servarr team and projects such as Readarr/Sonarr/Radarr. For heavy users who build their own audio and video libraries and want to “organize listening and reading books in one stop”, it is a new option worthy of attention, but please make a backup first.
Chapter
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10
A modern Windows multi-protocol network client rewritten in WPF
⭐ Total stars 673 ｜ Language C# ｜ Created on 2026-05-20
Se7en Pro is a Windows network client based on WPF (.NET 8) and Material Design 3. It adopts a single-process native architecture and MVVM mode. It focuses on fast startup, smooth animation, and low memory usage.
Architecturally, it integrates multiple network protocols into one interface: including WireGuard, Psiphon, Tor (with pluggable transmission), as well as multi-hop relay capabilities of sing-box and Xray. At the bottom, Wintun TUN and tun2socks complete kernel-level routing, supporting application-based offloading and leak prevention; the project also emphasizes that no private credentials or server lists are saved in the source code and Git history, and the construction key is passed through GitHub Actions Secrets Injection to facilitate public checkout and secondary construction.
The license is MIT, and the README provides instructions in Chinese, English, French, Russian and other languages. It performs ReadyToRun pre-compilation optimization for performance, and the interface adopts a responsive tray design. It is suitable for users who want to manage multiple network connection methods in a modern interface. Please pay attention to and comply with the relevant local laws and regulations before using it.
Se7en Pro
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