# objective-see/LuLu

LuLu is the free open-source macOS firewall

Repository: https://github.com/objective-see/LuLu
Canonical: https://ross.abutalabs.com/products/lulu
Homepage: https://objective-see.org/products/lulu.html
Language: Objective-C
License: GPL-3.0
License Family: copyleft
Last push: 2026-08-05T16:19:32+00:00

## Health v2 (maintenance only)
Score: 97/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 96, release rhythm 96, longevity 100
- inputs: {"age_days": 3279, "days_push": 28, "days_rel": 28, "gap_med": 13.5, "n_releases_24m": 25}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 13103, forks 597 (observed 2026-08-28T04:11:02.146099+00:00)

## What it is
LuLu is a free, open-source macOS firewall that monitors and blocks unknown outgoing network connections. It uses a system extension and network filter to alert users when applications attempt to connect to the network, protecting privacy and stopping malware communication.

## Use cases
- block unknown outgoing connections on my mac
- free open-source firewall for macOS
- monitor which apps are making network connections
- stop malware from phoning home
- alternative to Little Snitch
- control per-application network access on macOS

## When to choose
- you want a free, open-source macOS firewall with active development
- you need alerts and rules for outbound connections from applications
- you want privacy protection against unauthorized network activity by apps or malware

## When to avoid
- you need a firewall for Linux or Windows
- you only need inbound port filtering, which macOS's built-in firewall already provides
- you run macOS older than 10.15

## Facets
- artifact type: application
- maturity: active
- function: security, networking, privacy
- domain: security, privacy, apple-ecosystem
- platform: -
- tags: firewall, macos-firewall, network-filter, outbound-connections, system-extension, objective-see, macos

## Member repositories
- objective-see/LuLu (main) score 97

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:02.146099+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:13:31.998041+00:00, confidence not recorded.
  - readme: https://github.com/objective-see/LuLu (fetched 2026-08-28T04:11:02.146099+00:00, sha 3cde8fe36825)
  - homepage: https://objective-see.org/products/lulu.html (fetched 2026-08-29T08:08:56.736881+00:00, sha 27c83b8f8fb1)
- Data as of 2026-08-30T08:39:29.467469+00:00.