simdjson is a high-performance C++ JSON parsing library that uses SIMD instructions (AVX2, AVX-512, NEON, RVV, etc.) to parse and validate JSON at multi-gigabyte-per-second speeds. It provides two primary APIs: a DOM API (`simdjson::dom`) that builds a complete in-memory tree, and an On-Demand API (`simdjson::ondemand`) that performs lazy, forward-only parsing for streaming and large-document use cases. The library also includes a builder API for JSON serialization, compile-time JSON parsing via C++26 reflection, JSON Pointer/Path support, NDJSON/JSON-sequence streaming, and a single-header amalgamated distribution. The codebase is organized around a two-stage pipeline: stage 1 performs SIMD-accelerated structural indexing and UTF-8 validation, and stage 2 builds the DOM tape or drives the on-demand iterator. Runtime CPU dispatch selects the best implementation for the host architecture, with fallbacks for non-SIMD platforms. The repository is a mature, production-grade library used by major projects (Node.js, ClickHouse, etc.) and is backed by an extensive test suite, fuzzing harnesses, and cross-architecture CI. It is primarily an application/library rather than a data-research repository, though it contains benchmark and research-oriented components (e.g., performance modeling, static reflection experiments).
AsmJit is a low-level C++ library for runtime machine-code generation and execution (JIT compilation). It is not an application but a reusable library, with its main entry points in `asmjit/core.h`, `asmjit/x86.h`, `asmjit/a64.h`, and `asmjit/ujit.h`. The library provides three emitter tiers built on a shared emitter abstraction: `BaseAssembler` for direct binary encoding, `BaseBuilder` for node-based IR manipulation, and `BaseCompiler` for high-level code with virtual registers, liveness analysis, and automatic register allocation. The x86/x64 and AArch64 backends are the primary production targets; AArch32 database infrastructure exists but is not a fully implemented backend.
Capstone is a multi-architecture disassembly engine written in C, derived from LLVM's MC disassembler. It supports over 20 architectures including x86, ARM, AArch64, MIPS, PowerPC, RISC-V, and more. The core library provides a stable C API (cs_open, cs_disasm, cs_option, etc.) and includes per-architecture backends with mapping, disassembler, and instruction printer modules. The architecture is modular: each architecture has a Module.c that registers callbacks into a common cs_struct. The primary data flow is: user provides raw bytes and arch/mode, the engine selects the appropriate disassembler, decodes instructions into MCInst, then prints via instruction printer, optionally filling cs_detail with operand/register/group information. The repository also includes a CLI tool (cstool), extensive test suites (MC regression tests, cstest YAML-based detail tests), fuzzing harnesses, and an automated LLVM sync pipeline (auto-sync) that translates LLVM C++ disassembler code to C using tree-sitter patches. The codebase is well-structured with clean abstractions for operand models (MCInst/MCOperand), string output (SStream), and architecture-specific mapping. The auto-sync tooling is a notable engineering achievement, enabling systematic translation of LLVM backend code to C. Language bindings for Python, Java, OCaml, and others demonstrate the library's embeddability. The test infrastructure is comprehensive, covering both basic disassembly and detailed operand/register analysis. External dependencies are minimal for the core library (pure C), but the auto-sync tooling depends on Python, tree-sitter, clang-format, and lit. Overall, Capstone is a mature, actively maintained disassembly framework with high craftsmanship and reusable components.
This repository implements 'moss', a monolithic, Unix-like operating system kernel written in Rust, targeting AArch64 (with stubs for x86_64). It boots on QEMU and aims to run unmodified Linux userspace binaries (e.g., bash, coreutils, strace) by providing a Linux-compatible syscall interface. The kernel features an asynchronous core: all non-trivial syscalls are async functions, and the scheduler (EEVDF) and synchronization primitives are designed for async operation. The architecture includes a Hardware Abstraction Layer (HAL) via the `Arch` trait, but the majority of the code is ARM64-specific, covering boot, exception handling, MMU, interrupt controllers (GICv2/v3), UART drivers, timers, RTC, virtio, and a virtio-GPU display driver. The kernel provides a full process model with clone, execve, signals, futex, epoll, inotify, ptrace, and POSIX credentials. Memory management includes demand paging, copy-on-write, mmap, brk, a slab allocator with per-CPU caches, and a buddy allocator for physical frames. The VFS supports multiple filesystems: tmpfs, ext4 (via the ext4plus crate), FAT32, procfs, devfs, sysfs, and a cgroupfs stub. Networking uses the smoltcp stack for TCP/UDP and provides Unix domain sockets. The codebase is experimental and contains many stubs and unimplemented syscalls, but it is actively developed with a working init process, shell, and basic tools. Key strengths include the clean separation of architecture-independent kernel building blocks in the `libkernel` crate, the async-friendly synchronization primitives (`WakerSet`, `CondVar`, `Mutex`), the generic page table framework, and the driver registration macro. The code is well-structured for a kernel of this complexity, with extensive use of Rust's type system for safety (e.g., typed addresses, user-copy abstractions). However, the project is not production-hardened, relies on nightly Rust, and has significant architecture-specific code that limits portability.
Visor is a modern, feature-rich UEFI boot manager written in C, targeting x86_64 and AArch64. It provides a fast, graphically appealing boot menu with auto-detection of operating systems (Linux via EFI stub or raw bzImage, Windows chainload, and other EFI executables). The system is built as a single self-contained EFI binary (~340 KB) using the gnu-efi toolchain, with a sophisticated feature build system that allows compiling optional capabilities (GUI, animations, audio, encryption, TPM, GPT repair, etc.) into lightweight profiles. It supports Secure Boot (including shim), TPM measured boot, LUKS encrypted boot, btrfs snapshot management (snapper/timeshift), BLS/OSTree deployments, and animated backgrounds (GIF, MJPEG, MP4, custom VBG codec). Configuration is done via a plain-text `boot.conf` file, and a companion CLI tool (`visor`) handles installation, updates, kernel encryption, and asset conversion. The codebase demonstrates high craftsmanship through its modular architecture, comprehensive feature stubbing, custom decoders (PNG, JPEG, GIF), GPT repair logic, and hardware-level audio driver (HDA).
This repository is an educational companion to the book 'Programming with 64-Bit ARM Assembly Language', adapted for Apple Silicon (ARM64 macOS, iOS, watchOS, tvOS). It contains 16 chapters of progressively complex assembly examples, covering system calls, memory addressing, functions, floating-point, NEON, and optimization. The code demonstrates key differences between Linux and Darwin (Apple) ABIs, such as syscall numbers, addressing modes (ADRP/ADD vs LDR =symbol), and variadic function calling conventions. It includes reusable debug macros (printReg, printStr) for register inspection, file I/O macros, and a toupper function callable from C, Python, and Swift. The project also features an Xcode SwiftUI app that integrates assembly code across multiple Apple platforms. The repository is well-maintained and actively used as a reference for Apple Silicon assembly development.
Unicorn Engine is a lightweight, multi-architecture CPU emulation framework derived from QEMU. It provides a pure C API with bindings for Python, Go, Java, Rust, Ruby, .NET, Haskell, Pascal, Zig, and VB6. The engine supports ARM, ARM64, M68K, MIPS, PowerPC, RISC-V, S390X, SPARC, TriCore, and x86 (16/32/64-bit). It is used primarily for security research, reverse engineering, fuzzing, and dynamic analysis of binary code. The architecture is a library with a central C API that exposes memory mapping, register access, hooks (code, block, memory, interrupt, instruction, syscall, TLB), and context save/restore. The core emulation logic is based on QEMU's TCG (Tiny Code Generator) for dynamic binary translation, with a custom glib compatibility layer to eliminate external dependencies. The repository includes extensive regression tests, fuzz targets, and sample programs for each architecture and binding. While the engine is actively maintained and widely used, it carries technical debt from its QEMU fork (based on QEMU 5.0.1) and auto-generated binding constants that may drift from the C API.
Notepad4 is a Windows-based source code editor built on the Scintilla editing component. It provides syntax highlighting for over 50 programming languages, dark mode support, a plugin system (including the matepath file browser), and standard editing features such as find/replace, code folding, and auto-completion. The application is designed for developers seeking a lightweight yet feature-rich editor with extensive language support. The architecture is modular, separating the core editor (Notepad4) from plugins like matepath. The core editor uses Scintilla for text rendering and editing, with a custom wrapper (SciCall.h) to provide type-safe access to the Scintilla API. Language-specific lexers are maintained in the src/EditLexers directory, with many generated from keyword lists to ensure accuracy. Configuration is managed via INI files, and localization is supported through resource DLLs for multiple languages. Key external dependencies include Scintilla (for the editing core), Boost.Regex (for regular expression search), and the Windows API (for GUI, shell integration, and system services). The project demonstrates attention to modern Windows features such as Hi-DPI support, dark mode, and multi-monitor awareness. While the codebase is Windows-centric, it maintains clean separation between concerns through well-defined interfaces and encapsulation.
Ventoy is a production-grade tool for creating multi-boot USB drives that can boot ISO, WIM, IMG, VHD(x), and EFI files without reformatting the drive. The system operates by installing a custom bootloader stack onto a USB drive, then at boot time using a modified GRUB2 bootloader to present a menu of available images. When an image is selected, a custom initramfs (cpio archive) containing BusyBox and device-mapper tools is loaded, which creates a virtual block device mapping the image's sectors to the physical disk, allowing the OS to boot as if from a real CD/DVD. The architecture spans multiple layers: a UEFI/BIOS boot chain (GRUB2, iPXE, wimboot, EDK2), a runtime initramfs environment, and host-side installation/configuration tools (Windows GUI, Linux Qt/GTK/WebUI, CLI). It supports x86, x86_64, ARM64, and MIPS64EL architectures, and includes per-distro initramfs hooks for over 100 Linux distributions, Windows, and Unix variants (FreeBSD, DragonFly). External dependencies include heavily modified versions of GRUB2 2.04, EDK2 (stable201911), iPXE, wimboot, squashfs-tools, exfat, and embedded libraries like fat_io_lib and xz-embedded. The project is actively maintained with frequent releases and a large community.
simplewall is a native Windows desktop application that functions as a personal firewall using the Windows Filtering Platform (WFP). It controls per-application network access via user-defined rules and blocklists, including built-in Microsoft spy/telemetry lists. The application provides a full GUI with tabs for applications, services, UWP packages, rules, network connections, and logs, along with a tray icon, notification popups, and a rule editor. It logs allowed/blocked connections to a CSV file and supports real-time network monitoring via TCP/UDP statistics (including ETW-based UDP accounting). Profiles are stored in XML format with optional compression and AES encryption, and filters can be installed permanently, temporarily, or at boot time. The architecture is a monolithic C/C++ Win32 application with a custom utility library ("routine") as a submodule. Key modules handle WFP filter lifecycle, WFP net event subscription, network connection enumeration, security descriptor management, and UI controls (listview, search bar, notifications). The code demonstrates deep Windows internals knowledge, including WFP version-specific callbacks, ETW session management, cryptographic hashing, and digital signature verification. While the application is actively maintained (latest beta v3.9.1 as of July 2026), it is tightly coupled to Windows APIs and contains workarounds for historical Microsoft bugs, leading to moderate technical drift risk. Strengths include comprehensive WFP integration, robust logging, and a well-organized codebase with reusable patterns for WFP security (ACL management) and ETW-based UDP monitoring. Weaknesses include reliance on a private library submodule, hardcoded service/port lookup tables, and Windows version-specific branches that may need adjustment for future releases. The project is suitable for developers seeking a reference implementation for WFP firewall development or a reliable Windows filtering tool.
UEFI:NTFS is a UEFI bootloader application that enables booting from NTFS or exFAT partitions on UEFI systems lacking native drivers for these filesystems. It is primarily designed for use with Rufus to create bootable USB drives with Windows installation media or Windows To Go. The bootloader loads a filesystem driver (NTFS or exFAT), mounts the target partition, and chain-loads the standard UEFI bootloader from that partition. The source code is clean, well-commented, and demonstrates careful handling of UEFI firmware quirks, such as driver conflicts and Secure Boot validation. The project compiles with either gnu-efi or EDK2, supports multiple architectures (x86, x64, ARM, ARM64, RISC-V, LoongArch), and includes Visual Studio and GCC build configurations with CI pipelines. While the code is not reusable outside of UEFI development, it serves as a high-quality reference for writing UEFI applications and chain-loaders.
This repository is a Jekyll-based static website that serves as a comprehensive database of PCI Express device compatibility with Raspberry Pi Compute Module 4 and Pi 5. It contains hundreds of markdown files documenting individual PCIe cards, carrier boards, and HATs, along with their functionality status, driver requirements, and community testing notes. The site is automatically built and deployed to GitHub Pages via GitHub Actions. While primarily a content site, it includes useful extras like a cross-compilation Docker environment for building custom Pi kernels, which is the most technically sophisticated component. The codebase is straightforward Jekyll with some custom plugins for thumbnail generation and YouTube embeds. The project is actively maintained with frequent additions of new hardware listings.
Tina is a header-only library providing lightweight user-space threading through coroutines and fibers, along with a fiber-based job system for task scheduling. The core library (tina.h) implements symmetric and asymmetric coroutine APIs with platform-specific assembly for context switching. Tina Jobs (tina_jobs.h) builds on this to create a job scheduler featuring work-stealing via queue chaining, memory pooling, and fiber-based job execution to avoid OS thread overhead. The repository includes examples (e.g., Mandelbrot renderer using Sokol graphics) and tests demonstrating usage, but the project has migrated to Codeberg due to philosophical opposition to AI training, indicating the GitHub repository is no longer actively maintained. While the Sokol dependencies in extras are third-party, the Tina core showcases strong craftsmanship in low-level concurrency primitives.
This repository is the build and packaging meta-repo for Hangover, a project that enables running x86 Windows applications on ARM64 Linux by combining Wine with CPU emulators (FEX, Box64). It contains CI workflows (GitHub Actions) that build Wine with ARM64EC support, compile emulator DLLs, and produce Debian/Ubuntu packages. The actual source code resides in submodules (wine, fex, box64). The repository itself is purely infrastructure: Dockerfiles, debian packaging files, and a complex multi-stage CI pipeline. It is actively maintained with regular releases. There are no reusable software components; the value is in the integration and packaging, not in original code.