For configuration-driven code (especially anything that affects user-facing URLs, published links, secrets, or server startup), centralize resolution and make precedence explicit. Apply these rules: 1) Use a single “resolver” per concept (e.g., user-facing base URL, webhook secret). All output paths must use it—no bypasses. 2) Define and document an explicit precedence order. Prefer dedicated user-facing settings over API/internal settings. 3) Handle “shipped defaults” safely: treat the default value as non-overriding (compare against a DEFAULT constant) so real deployments don’t regress. 4) Avoid duplicated fallback expressions for secrets/configs. Keep backwards compatibility in the resolver, not scattered across handlers. 5) Use consistent config access (`get_settings().get(...)`) and prefer config/env-backed values for ports. Example (user-facing URL resolver pattern): ```python DEFAULT_GITEA_URL = "https://gitea.com" def resolve_user_facing_base(pr, owner, repo, pr_number, base_url: str) -> str: web_url = (get_settings().get("GITEA.WEB_URL", "") or "").rstrip("/") if web_url: return web_url configured = (get_settings().get("GITEA.URL", "") or "").rstrip("/") if configured and configured != DEFAULT_GITEA_URL: return configured pr_html_url = getattr(pr, "html_url", "") if pr else "" suffix = f"/{owner}/{repo}/pulls/{pr_number}" if pr_html_url and pr_html_url.endswith(suffix): return pr_html_url[: -len(suffix)] return base_url ``` Then ensure every user-facing link builder (comments, changelog links, review links) uses this resolved base, not the API/internal `base_url`.