Brave Core

Brave Core is a set of changes, APIs, and scripts used for customizing Chromium to make the Brave browser. Please also check https://github.com/brave/brave-browser which only holds the issues, releases and the wiki.

Overview

This repository holds the build tools needed to build the Brave desktop browser for all platforms. In particular, it fetches and syncs code from the projects defined in package.json and src/brave/DEPS:

• Chromium
  • Fetches code via depot_tools.
  • Sets the branch for Chromium (ex: 65.0.3325.181).
• brave-core
  • Mounted at src/brave.
  • Maintains patches for 3rd party Chromium code.
• adblock-rust
  • Implements Brave's adblock engine.
  • Linked through brave/adblock-rust-ffi.

Resources

• Documentation and guides
• Issues
• Releases
• Wiki

Downloads

You can visit our website to get the latest stable release.

Contributing

Please see the contributing guidelines.

Our Wiki also has some useful technical information, especially about setting the development environment.

Security Policy

Please see the security policy.

Community

Join the Q&A community if you'd like to get more involved with Brave. You can ask for help, discuss features you'd like to see, and a lot more. We'd love to have your help so that we can continue improving Brave.

You can also ask questions and interact in the community-guest channel on Brave Software's Slack.

Help us translate Brave to your language by submitting translations at https://explore.transifex.com/brave/brave_en/.

Follow @brave on X for important news and announcements.

Install prerequisites

Follow the instructions for your platform:

• Android
• Linux
• iOS
• macOS
• Windows

Clone and initialize

Once you have the prerequisites installed, you can get the code and initialize the build environment.

git clone git@github.com:brave/brave-core.git path-to-your-project-folder/src/brave
cd path-to-your-project-folder/src/brave
npm install

# the Chromium source is downloaded, which has a large history (gigabytes of data)
# this might take really long to finish depending on internet speed

npm run init

brave-core based android builds should use npm run init -- --target_os=android --target_arch=arm (or whichever CPU type you want to build for) brave-core based iOS builds should use npm run init -- --target_os=ios

You can also set the target_os and target_arch for init and build using:

npm config set target_os android
npm config set target_arch arm

Additional config needed to build are documented at https://github.com/brave/brave-browser/wiki/Build-configuration

Internal developers can find more information at https://github.com/brave/internal/wiki/Build-configuration

Build Brave

The default build type is component.

# start the component build compile
npm run build

To do a release build:

# start the release compile
npm run build Release

brave-core based android builds should use npm run build -- --target_os=android --target_arch=arm or set the npm config variables as specified above for init

brave-core based iOS builds should use the Xcode project found in ios/brave-ios/App. You can open this project directly or run npm run ios_bootstrap -- --open_xcodeproj to have it opened in Xcode. See the iOS Developer Environment for more information on iOS builds.

Build Configurations

Running a release build with npm run build Release can be very slow and use a lot of RAM, especially on Linux with the Gold LLVM plugin.

To run a statically linked build (takes longer to build, but starts faster):

npm run build -- Static

To run a debug build (Component build with is_debug=true):

npm run build -- Debug

NOTE: the build will take a while to complete. Depending on your processor and memory, it could potentially take a few hours.

Run Brave

To start the build:

npm start [Release|Component|Static|Debug]

Update Brave

npm run sync -- [--force] [--init] [--create] [brave_core_ref]

This will attempt to stash your local changes in brave-core, but it's safer to commit local changes before running this

npm run sync will (depending on the below flags):

1. 📥 Update sub-projects (chromium, brave-core) to latest commit of a git ref (e.g. tag or branch)
2. 🤕 Apply patches
3. 🔄 Update gclient DEPS dependencies
4. ⏩ Run hooks (e.g. to perform npm install on child projects)

flag	Description
[no flags]	updates chromium if needed and re-applies patches. If the chromium version did not change, it will only re-apply patches that have changed. Will update child dependencies only if any project needed updating during this script run. **Use this if you want the script to manage keeping you up to date instead of pulling or switching branches manually. **
--force	updates both Chromium and brave-core to the latest remote commit for the current brave-core branch and the Chromium ref specified in brave-core/package.json (e.g. master or 74.0.0.103). Will re-apply all patches. Will force update all child dependencies. **Use this if you're having trouble and want to force the branches back to a known state. **
--init	force update both Chromium and brave-core to the versions specified in brave-core/package.json and force updates all dependent repos - same as npm run init
--sync_chromium (true/false)	Will force or skip the chromium version update when applicable. Useful if you want to avoid a minor update when not ready for the larger build time a chromium update may result in. A warning will be output about the current code state expecting a different chromium version. Your build may fail as a result.
-D, --delete_unused_deps	Will delete from the working copy any dependencies that have been removed since the last sync. Mimics gclient sync -D.

Run npm run sync brave_core_ref to checkout the specified brave-core ref and update all dependent repos including chromium if needed.

Scenarios

Create a new branch:

> cd src/brave
src/brave> git checkout -b branch_name

Checkout an existing branch or tag:

src/brave> git fetch origin
src/brave> git checkout [-b] branch_name
src/brave> npm run sync
...Updating 2 patches...
...Updating child dependencies...
...Running hooks...

Update the current branch to the latest remote:

src/brave> git pull
src/brave> npm run sync
...Updating 2 patches...
...Updating child dependencies...
...Running hooks...

Reset to latest brave-core master (via init, will always result in a longer build and will remove any pending changes in your brave-core working directory):

src/brave> git checkout master
src/brave> git pull
src/brave> npm run sync -- --init

When you know that DEPS didn't change, but .patch files did (quickest attempt to perform a mini-sync before a build):

src/brave> git checkout featureB
src/brave> git pull
src/brave> npm run apply_patches
...Applying 2 patches...

Enabling third-party APIs

1. Google Safe Browsing: Get an API key with SafeBrowsing API enabled from https://console.developers.google.com/. Update the GOOGLE_API_KEY environment variable with your key as per https://www.chromium.org/developers/how-tos/api-keys to enable Google SafeBrowsing.

Development

• Security rules from Chromium
• IPC review guidelines (in particular this reference)
• Brave's internal security guidelines (for employees only)
• Rust usage

Troubleshooting

See Troubleshooting for solutions to common problems.