When updating an Arch-based system (like CachyOS) via AUR helpers, we are executing arbitrary build scripts (PKGBUILD and .install scripts) written by community members. During supply chain incidents, relying on manual human checks is a massive liability.

This post serves as a high-signal reference to automate static analysis on these scripts natively before compilation.

The Architecture: Before vs. After

Architecture Diagram

Security Execution Matrix

Metric Before Integration After Integration
Verification Gate Manual scrolling (Human eye) Automated regex parser + human backup
Halt Condition User notices anomaly and presses Ctrl+C Exit Code 1 from PreBuildCommand kills loop
Verification Speed Slow, prone to fatigue Instant (Milliseconds via Babashka)
Audit Scope Only files shown in the pager Deep scan of both PKGBUILD and .install scripts
Vulnerability Signatures None Scans for curl/wget payloads, systemd persistence, profile injections

System Integration Commands

To configure this setup, we link our scanner to our local userspace path and hook it directly into paru’s execution engine.

We place the compiler/script within our local userspace bin directory:

ln -sf ~/ Documents/Bugs/aur-audit/aur-audit.clj $HOME/.local/bin/aur-audit
chmod +x $HOME/.local/bin/aur-audit

2. Native Paru Hook configuration

Append the pre-build trigger configuration to your local paru.conf file:

# ~/.config/paru/paru.conf
[options]
PreBuildCommand = ~/ .local/bin/aur-audit

Threat Scanner Flow

Whenever a build begins, the pre-build phase executes the following logic inside the package source directory:

Architecture Diagram

With this integration, you establish a system-enforced defense gate that eliminates cognitive fatigue during package upgrades.