In Tool Tuesday #1 we walked through Temporal. The reader question we got most was: "okay but should I just use Inngest?" Here is the honest answer.
The two tools, in one sentence each
Temporal is a durable execution engine: long-running stateful workflows, code-as-DAG, history-replay determinism. Inngest is an event-driven function platform: durable steps with a simpler programming model, a queue and a scheduler bolted on, and dramatically less ops surface area.
Mental model: where they actually differ
Temporal asks you to think about your business logic as a deterministic state machine. Inngest asks you to think about it as a sequence of steps reacting to events. The end-state is similar; the day-to-day code feels very different. Inngest will land in your codebase as a few decorators. Temporal will land as an architectural decision the whole team has to internalise.
The three shapes where Inngest is right
- Most workflows are under 30 minutes end-to-end and event-triggered.
- The team is small and the ops budget is "we already pay for one PaaS, we are not adding a second cluster".
- The state model fits step functions cleanly - read, transform, write, occasionally branch, occasionally retry.
The three shapes where Temporal is right
- You have multi-day or multi-week workflows with human-in-the-loop steps and signals.
- Determinism and exact replay are a hard requirement (regulated industries, financial reconciliation).
- You already operate Kubernetes well, and you have a platform team that owns infrastructure as a product.
Pricing reality check
Inngest's usage-based pricing is honest at small scale and can become expensive once you cross ~10M steps a month. Temporal Cloud's pricing is honest at large scale and can be hard to justify under ~5M actions a month. Self-hosted Temporal pays off only if you have a real platform team. Self-hosted Inngest exists; almost nobody does it.
The hybrid case
Two of the most interesting setups we saw this quarter use both: Inngest for short event-driven flows (webhooks in, side-effects out) and Temporal for the few long-running workflows (annual renewals, multi-step billing reconciliation). Each in the layer where it is best.
Coming next
Tool Tuesday #3 will cover Trigger.dev - the third option that gets unfairly skipped in this conversation.