- server/credentials.py: PBKDF2 password + session secret, 0600 json, one-time setup command (server refuses to start without it) - app.py: signed 30-day cookie (itsdangerous), middleware 401s API / redirects pages to /login?next=, 5-fail/15-min lockout, /logout - static/login.html: dark-themed form, inline error display - app.js: api() 401 -> redirect to /login preserving current URL - docs: README quick start + features, SPEC auth section