Offline parental controls for Linux (no cloud, no biometrics) Open-source project

We’re part of the team behind BigLinux, a Brazilian Linux distribution.

Recently, Brazil passed a new law introducing requirements around age verification, parental controls, and protection of minors online. The discussion around it quickly turned into confusion, misinformation, and speculation — especially about what would be technically required.

Instead of guessing, we decided to build a concrete implementation.

We created an open-source project called big-parental-controls, a native parental control suite for Linux designed to comply with the law while preserving user privacy and system autonomy.

GitHub: https://github.com/biglinux/big-parental-controls

Design approach

We intentionally avoided the common industry pattern of cloud-based monitoring and identity verification.

• Fully offline / local-only
  All configuration and activity data stays on the device. No cloud, no remote APIs, no telemetry.

• No biometrics or external identity checks
  The system relies on the responsible adult configuring the machine and declaring the age group. No document validation, no external services.

• Built with native Linux components

  • Application control via ACLs

  • DNS filtering using nftables

  • Screen time enforcement through PAM

  • Visible system tray indicator when monitoring is active

• User-controlled data
  Activity data can be exported or deleted at any time by the administrator, aligning with privacy regulations.

Why this matters

Most parental control solutions today depend on centralized infrastructure, user tracking, or invasive verification methods. We wanted to explore whether it’s possible to meet legal requirements without introducing surveillance or external dependencies.

This project is our attempt at that balance.

A note on trade-offs

While we made this tool available, not everyone on the team sees this as a positive direction.

Many developers got started by having unrestricted access to systems — experimenting, breaking things, and learning by doing. There’s a concern that overly restrictive interpretations of such regulations could unintentionally limit that path for younger users.

Looking for feedback

The project is fully open source and available for anyone to use, adapt, or critique.

We’d be interested in hearing from others:

• How would you approach this problem?

• Is a fully local model enough to satisfy regulatory expectations?

• What trade-offs would you make differently?

Source: https://forum.biglinux.com.br/d/5873-biglinux-e-a-lei-felca-eca-digital--biglinux-and-the-eca-digital