outlay's core solver is pure arithmetic: no network access, no filesystem access, no eval, and no runtime dependencies. The outlay/html subpath adds one runtime dependency, htmlparser2, and outlay/pretext uses the optional @chenglou/pretext peer; nothing else pulls in third-party code. The attack surface is limited to pathological input trees (e.g. adversarially deep nesting causing stack exhaustion).

Report vulnerabilities privately via GitHub Security Advisories. Do not open a public issue for security reports.

You can expect an acknowledgment within a week. Fixes ship as patch releases with the advisory credited unless you prefer otherwise.