SIMBA vs Vapi
Developer platform for voice AI with flexible primitives
Vapi gives developers a flexible, API-driven way to build voice agents with granular control. SIMBA ships the same real-time voice stack plus a deterministic workflow editor, native CRM and helpdesk integrations, evals, and enterprise governance — the difference between a toolkit and a finished product.
At a glance
Where SIMBA is stronger
Platform over primitives
Vapi gives you excellent voice primitives and expects you to assemble the rest. SIMBA ships the whole shape: workflow editor, knowledge base, tool library, CRM writebacks, analytics, evals, and enterprise controls.
Deterministic workflow guardrails
Define scripts, branching logic, and mandatory fields for regulated flows (billing, collections, healthcare intake). Agents follow the rules consistently — not just when the LLM decides to.
Native helpdesk and CRM writebacks
Log calls to Salesforce, update Zendesk tickets, and push deal updates to HubSpot without custom code.
Evals built in
Simulated callers, scoring rubrics, and regression detection ship standard — so prompt changes don't surprise you in production.
Enterprise-grade by default
SOC 2 Type II, ISO 27001, HIPAA-ready, SSO, RBAC, audit logs, zero retention, and regional data residency are standard — not behind custom sales.
Where Vapi may be a better fit
Flexible developer experience
Vapi's strength is giving developers a lot of knobs. If your requirement is "we'll write it ourselves," Vapi is a solid toolkit.
Model-agnostic routing
Vapi makes it easy to swap models and providers. SIMBA offers the same flexibility, but Vapi's developer surface for it is particularly clean.
Feature-by-feature
Choose SIMBA when
- You want a complete platform out of the box, not primitives to assemble.
- You need deterministic workflows and evals for regulated or high-stakes conversations.
- Compliance matters: HIPAA, SOC 2, SSO, RBAC, audit logs, and data residency.
- You want forward-deployed engineers, not just documentation.
Choose Vapi when
- You have the engineering capacity to build around a toolkit and prefer maximal flexibility.
- Your team values minimal product surface area and wants to own the agent logic end-to-end.
Frequently asked questions
Is SIMBA as flexible as Vapi for developers?
SIMBA offers the same code-first flexibility via our SDK and REST API, and adds a visual workflow layer for non-developers — so engineering and operations can collaborate on the same agent.
Can I use my own LLM with SIMBA?
Yes. SIMBA routes to OpenAI, Anthropic, Google, open-source models, or your own hosted endpoint.
What about migrating existing Vapi assistants?
Prompts, function/tool definitions, and voice configs map over to SIMBA directly. Our Enterprise migration team helps port configurations and validate parity with simulated callers.
How does total cost compare?
Vapi's per-minute rate is comparable, but SIMBA bundles integrations, evals, and compliance features you'd otherwise buy separately or build.
See SIMBA on your workload
We'll run a parallel eval against your current platform using real call data and show you the numbers before you commit.