AWS Step Functions vs Camunda for Sagas: Two Orchestrators, Different Blast Radii
Here's a trap I've watched smart teams walk into. They pick a saga orchestrator by comparing the two engines feature-for-feature, decide they both "do sagas," flip a coin weighted by whatever's already in their cloud bill, and move on. Then a year later one team is tuning Zeebe partitions at 2am and the other is staring at a Step Functions bill that grew faster than their traffic, both wondering…
A common mistake made by smart teams is selecting a saga orchestrator by comparing feature-for-feature, deciding they both do sagas, and moving on. However, a year later one team finds themselves tuning Zeebe partitions at 2am while the other is staring at a Step Functions bill that has skyrocketed faster than their traffic. Despite running the same pattern, the experience varies greatly.
A saga is a sequence of local transactions where, if a step fails, you execute compensating actions to undo previous steps. Both AWS Step Functions and Camunda 8 are orchestration-style saga coordinators, central brains that know the steps, drive them in order, and trigger rollback when something breaks. The major difference lies in what you are responsible for.
Step Functions, managed by AWS, is a state machine where you define your saga in Amazon States Language, a JSON-based format. AWS then runs the state machine, handling retries and error routing declaratively. The compensation logic, however, falls on you, requiring you to manually point each step's Catch block to the appropriate cleanup state and undo the successful steps.
There is no built-in primitive to compensate the entire saga in one go. For long-running sagas, AWS offers Standard Workflows, which bill per state transition. Every task, wait, and choice adds to the bill, making it a costly option for high-volume, short-lived sagas due to retries and compensation steps.
In contrast, Camunda 8 offers a different approach. It still requires an orchestrator to centralize process state, drive the next step, and manage compensation logic. However, Camunda 8 provides an inbox for human steps, task lists with assignment and escalation features, and built-in retry logic that doesn't bill for each retry attempt.
This reduces the operational burden during failure scenarios, where retries and compensation steps are most likely to occur and bill the most. Thus, the choice between Step Functions and Camunda 8 for sagas isn't about which has more features, but which failure scenario you are willing to own.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
