Own your assistant, end to end

Rasa is the open-source standard for teams that can’t hand their conversational data to a third party. You run the whole stack on your own infra, train custom NLU, and orchestrate with CALM (Conversational AI with Language Models) for grounded, controllable dialogue. We stood up a banking assistant on-prem in a day — something closed SaaS simply can’t offer.

Who it's for: Engineering teams in regulated industries (finance, healthcare, gov) and anyone who needs full data control and custom ML.

Key features

Open Self-hosted

Run everything on your own servers — no data leaves your VPC. GDPR and SOC2 friendly by design.

CALM Grounded dialogue

The new CALM layer uses LLMs for natural conversation while keeping actions constrained and verifiable.

NLU Custom models

Train intent and entity models on your domain data; no black-box classifier.

Integrate Channels & APIs

Connect to web, Slack, WhatsApp, and your backend via flexible actions.

Scale Enterprise tier

Rasa Pro adds observability, support, and advanced features for production fleets.

The honest take

✓ What works

Full data ownership and on-prem deployment
CALM gives controllable LLM dialogue
Huge open-source community and docs
Free for most self-hosted use

✗ What doesn't

Steeper learning curve than no-code bots
You own uptime and infra
Best value needs engineering talent
enterprise features sit behind Rasa Pro

Verdict

If data control is non-negotiable, Rasa is the only serious game in town. The CALM upgrade finally makes LLM-powered assistants safe for production. Bring engineers — but you’ll own the result.

💡 Transparency: This review contains affiliate links. If you sign up through our link, we may earn a commission at no cost to you. We only recommend tools we use ourselves. Full disclosure.