The Missing Semester is a free, open-source educational curriculum designed to bridge the gap between theoretical computer science and the practical tooling every software engineer needs. Organized as a structured course, it covers Unix shell mastery, version control with Git, software debugging and profiling, system administration fundamentals, and computer security practices — the skills often left out of traditional degree programs. The project is maintained as a collaborative set of lecture notes, exercises, and guides that function as both a professional development tools course and a Unix and Git mastery resource.
What distinguishes The Missing Semester is its unusually broad scope, extending from core command-line and shell scripting to contemporary workflows like AI-assisted code generation, containerization with Docker and Docker Compose, and integration with external services via MCP and web APIs. The curriculum also addresses data wrangling and text processing, desktop environment customisation, advanced web browsing techniques, and a full security module covering encryption, authentication, and network privacy. This range means a single course can take a learner from basic filesystem navigation through to structured logging, performance profiling, and automated software testing.
The course is delivered through a lecture-video-driven format with accompanying Markdown notes that are rendered into a static website. Content is maintained year by year using separate Git branches, and community-translated versions in dozens of languages are linked directly from the site. Anyone can contribute improvements via pull requests, making the resource itself a living example of the open-source collaboration practices it teaches.
