croc is a secure, peer-to-peer file transfer tool that operates via a relay server for NAT traversal. It uses Password Authenticated Key Exchange (PAKE) for authentication and end-to-end encryption (AES-GCM or ChaCha20-Poly1305) to protect data in transit. The application consists of a Go CLI client, a standalone web server (croc-web), and a React/Vite web frontend that uses WebAssembly to perform crypto operations in the browser. Files are split into chunks, optionally compressed, and transferred over multiple TCP connections with resume support. The tool also supports an asynchronous 'stored transfer' mode where encrypted files are temporarily stored on the relay server and can be downloaded by recipients using access tokens. The codebase is well-structured with a custom CLI framework, modular crypto and compression packages, and a comprehensive test suite covering core transfer logic, security properties, and end-to-end browser tests. The web client includes a blog with deep technical articles about the protocol design.

This is a well-crafted Go library providing a thread-safe, highly customizable progress bar for terminal applications. It supports both determinate (known maximum) and indeterminate (spinner) modes, with features like elapsed time, predicted time remaining, byte throughput, iterations per second, and configurable themes (including ASCII, Unicode, and custom). The library is designed for ease of use with convenient constructors (Default, DefaultBytes) and a fully functional options pattern for deep customization. It is used as an io.Writer in download scenarios and includes a built-in HTTP server for external monitoring of progress state. The codebase is clean, well-tested, and follows Go best practices.

This repository implements an end-to-end encrypted file transfer system called e2ecp. It consists of a Go-based relay server, a CLI client, and a React web frontend. The system allows users to transfer files or text between peers with zero-knowledge encryption: the relay server never sees plaintext data or metadata. It also supports user accounts with encrypted cloud storage, file sharing via links, device authentication, and email verification. The architecture is a monolith with a WebSocket relay, HTTP API, PostgreSQL database, and separate client implementations. Key entry points are the CLI (main.go), the relay server (src/relay/relay.go), and the React app (web/src/App.jsx). The codebase is well-structured with comprehensive testing, CI/CD, and Docker support. However, there are some maintenance risks such as duplicated protobuf schemas between Go and JavaScript, and the use of a future Go version (1.25) in go.mod, which may indicate dependency drift.