Per-execution dynamic credential selection for multi-tenant workflow automation (pick the tenant's credential at runtime)
Agencies and SaaS teams using n8n as their automation backend cannot choose which saved credential a node uses via an expression at runtime, so one logical workflow becomes 100+ duplicated nodes (one per client) or a fragile community-node hack. They want a single workflow that resolves the right per-tenant credential from the execution data. The canonical request thread is five years old and still drawing replies this week.
Don't build another Zapier; the wedge is multi-tenant. Agencies and SaaS embedding automation need one workflow that resolves a tenant's credential at execution time. The security-review burden of injecting arbitrary credential IDs is both the reason incumbents leave it static and the moat if you solve it safely (scoped, permissioned references rather than raw IDs).
landscape (3 existing solutions)
Every mainstream automation engine binds credentials statically, so multi-tenant builders duplicate nodes per client or hack around it. Declarative, secure runtime credential resolution is the unmet need; the security-sensitivity of injecting arbitrary credential references is exactly why engines keep it static.