CS 61C: Course Notes

Course notes for CS 61C. A Jupyter Book 2 project.

Contribute!

As of Spring 2026, these course notes are in active development. Due to course staff capacity, we may occasionally be unable to write course notes and will refer you to the lecture slides instead.

If you find an error in our first draft, please email cs61c@ or submit a pull request (PR) on GitHub.

How to make a PR

• See the GitHub docs for Creating a pull request.
• Suggestion: Use GitHub Desktop! You will need to use git command-line tools to work with course assignment repos. For starting out with open-source projects, we recommend using GitHub Desktop. This desktop app will help build the abstraction between what's on your local machine and what's on the remote GitHub origin. Read about how to use GitHub Desktop to create pull requests.

PR Etiquette

• Please batch edits together into one PR. Ideally, the largest batch size is a chapter or two (i.e., lecture or two). This helps us merge different branches together, particularly if the changes are related to one another.
  • Please make direct edits to files that are clearly typos or errors.
  • For concepts that could be worded better, please make suggested edits for things that could be worded better. It's helpful if you could include in the PR itself reasons why the wording is needed, or what is unclear.
  • For concepts you're unsure about, please feel free to ask on our course Ed discussion forum before making a PR.
• Keep your commit messages short by using semantic commit messages, e.g., fix(lec05): ..., fix(c-memory-management).
• Expand with more description in the content of your PR on GitHub. We can hold further comments and discussions on the GitHub PR.

Local Jupyter Book Setup

• If you have pip on your machine, follow the "Install with pip" instructions on the Jupyter Book website.
• Try locally serving the book: jupyter book start
• If the above command fails, you may need to try a different installation method---likely because jupyter is incorrectly configured on your machine . If you have npm, use that. Otherwise here are the uv instructions that work on Mac M1 chips. Create a virtual environment with uv and then install via uv pip.

uv venv
source .venv/bin/activate
uv pip install "jupyter-book>=2.0.0"
uv run --with jupyter jupyter book start # use this syntax for running all jupyter book commands

Deployment

This website is currently deployed at <notes.cs61c.org> via Cloudflare pages. If redeployment is needed, follow the below instructions, which assume a freshly forked copy of this repository, and redeployment to an entirely new Pages project:

Redeployment from a fresh repo

1. GitHub Setup
   1. Go to GitHub organization settings => GitHub Apps => Cloudflare Pages => Configure => Repository Access, and ensure that the app has access to this repository.
2. Create a Pages project in Cloudflare
   1. Login to Cloudflare
      1. If you are doing this for CS61C, please login as the CS61C Cloudflare account and use "CS61C DNS Account" to have access to the DNS records for <cs61c.org>
   2. Go to Workers and Pages => Create Application => Looking to deploy Pages? Get started
   3. Import an existing Git repository => Get Started
   4. Make sure GitHub account is set to whichever organization has this repository
   5. Select a repository => this repository's name => Begin Setup
   6. Set the following:
      • Production branch: main
      • Framework preset: None
      • Build command: bash build.sh
      • Build output directory: _build/html (see below)
   7. Click Save and Deploy. This should deploy the project. Once it completes, click "Continue to Project".
3. Configure a custom domain in the project
   1. Click "Custom domains" in the top navigation bar of the project
   2. Add a custom domain => enter the desired domain. (e.g. notes.cs61c.org
   3. Click "Continue"
   4. Make sure everything looks fine, then click "Activate domain". It may take up to 48 hours to propagate, but based on past experience, it is way faster than that.

If minor changes are needed, go to the existing Cloudflare Pages project (must be logged in to the CS61C Cloudflare), select "Settings" and configure as desired.

Cloudflare Pages expects:

• a directory with HTML source to serve as a static site: _build/html (mystmd docs), and
• a build command that generates that directory: bash build.sh wraps mystmd build which is installed from the pywrangler config pyproject.toml.