How do you handle a distributed transaction without two-phase commit?

Two-phase commit is rarely used in microservices because it needs a coordinating transaction manager, holds locks across services, blocks on coordinator failure and hurts availability. Instead, prefer an eventual-consistency design:

• Saga: model the workflow as local transactions with compensations (orchestrated or choreographed). Each step commits independently and failures trigger undo actions.
• Outbox pattern: write the business row and an event row in one local transaction, then publish the event asynchronously. This avoids the dual-write problem where a crash after the DB commit but before the publish loses the event.
• Idempotent consumers: deduplicate by message id or use upserts so retries and duplicate deliveries are harmless.
• Reconciliation: background jobs compare states and repair drift, and reads may use a read model projected from events.

BEGIN;
INSERT INTO orders ...;
INSERT INTO outbox (event_type, payload) VALUES ('order.created', :json);
COMMIT;

Choose compensations that are reversible or harmless, and make every step idempotent, because distributed atomicity is replaced by retries and repair.