SELO Block — Browser-level ad & data-broker blocker
Open-source Manifest V3 browser extension that uses Chrome's Declarative Net Request API to block ads, trackers, and data brokers natively in the browser engine, with a dedicated data-broker list and zero runtime performance cost.
Client: Open Source Project · Timeline: Active · Role: Solo developer — ruleset compiler, extension, UI
Stack: JavaScript, Chrome Declarative Net Request, Manifest V3, Node.js (build), Static rulesets, Manifest V3 native, Static rulesets, Data-broker focus
Problem
- JavaScript-based blockers run on every page load and can slow browsing on lower-end hardware.
- Data-broker domains — companies that buy and sell personal info — are rarely covered by mainstream ad-blocking lists.
Approach
- Built on Chrome's Declarative Net Request API (Manifest V3): rules execute in the browser engine rather than JS, for effectively zero runtime overhead.
- Compiled 10 static rulesets × 30,000 rules — 300,000+ domains merged from OISD, Steven Black Hosts, and AdGuard DNS.
- Added a dedicated 796-domain data-broker list and a one-click whitelist flow exposed in the popup UI.
Results
- Blocks 300,000+ domains across ads, trackers, and data brokers with no measurable performance impact.
- Real-time blocking statistics and per-site whitelisting available from the popup.
- MIT-licensed, no telemetry, no third-party data collection — fully auditable.
What you can verify
- MIT-licensed repo with rules-build script and reviewer-ready install steps.
- Architecture documented vs JS-based blockers (engine-level rules vs per-page JS).
- Packaged .xpi build available in repo for review.