Reasonix.io

Reasonix is a coding assistant you run directly in your terminal. It's not a plugin for your IDE or a web app. You install it as a single binary, navigate to your project directory, and start a session. From there, you can ask it to write code, refactor functions, or review changes. It works with your existing tools—git handles diffs, and your terminal is the workspace. This makes it feel like a natural extension of your command-line workflow.

What sets Reasonix apart is its focus on efficiency and cost. It's built specifically for DeepSeek's language models and uses a clever 'append-only' loop. This means each new request in a session reuses the exact same byte-for-byte prefix from the previous one. DeepSeek's servers can cache this prefix, so you only pay for the new tokens you generate. The page claims this leads to a 90%+ cache hit rate on long sessions, cutting input token costs to about one-fifth of the usual price. It also includes features like a plan mode for approval before writing files, support for MCP (Model Context Protocol) servers, and specialized sub-agents for tasks like security reviews.

This tool is for developers who live in the terminal. It's ideal for engineers working on long-running refactoring tasks, code reviews, or exploratory coding where you want an AI assistant to stay in context without racking up huge API bills. It's also useful for remote development, as you can SSH into a build server and run Reasonix there, keeping your coding session alive and cheap.