Per-vertical public podcast feed — one show per canonical taxonomy slug (tech / health / young_moms / science / finance / news). Each gets its own Spotify directory listing submission with vertical-flavored channel title + iTunes category.

Special case — vertical="trending": rounds out the URL pattern so every slug in PODCAST_VERTICAL_META resolves. Short-circuited through the all-trending root builder (vertical=None) since "trending" is a virtual cross-vertical slug, not a real vertical column value in articles / persona_briefings (there are no rows where vertical='trending' — see the briefing-vertical inventory in MEMORY 2026-05-30). Without this short-circuit, the per-vertical query path would 200 but emit zero items.

2026-06-05 · public URL alias resolution. The listener-facing show namespace is parenting (the post-pivot rebrand) but the canonical taxonomy key is still young_moms because the article- level vertical column hasn't been migrated yet. Without this alias table, /v1/podcasts/storyflo-parenting.xml 404s even though the listen-grid happily renders parenting cards. Spotify/Apple ingest on the publicly-shared -parenting.xml URL — must resolve. Aliases live HERE (request-edge) rather than in PODCAST_VERTICAL_META so the canonical metadata stays single- source-of-truth.