Retry
Re-execute the delegate when it fails, waiting between attempts.
Circuit Breaker
Stop hammering a dependency that's already failing. The breaker measures failures and, once a threshold is crossed, rejects executions outright for a break duration — giving the dependency room to recover.
Timeout
Bound how long an execution may take.
Rate Limit
A token-bucket limiter: Permits executions per Window, with bursts and optional queueing.
Concurrency Limit
Concurrency isolation: cap how many executions run at once, so one misbehaving dependency can't drain your whole thread pool or connection pool.
Hedging
Race parallel attempts against tail latency: if the first attempt hasn't answered within the hedge delay, fire a second one. Fastest success wins; losers are cancelled.
Fallback
When all else fails, degrade gracefully instead of throwing: return a default, a cached value, or anything you can compute from the failure.