Heysali: Building a Swiss B2B Sales Outreach Platform
Heysali is a Swiss B2B sales outreach platform that brings prospecting data, multi-channel email, and AI-assisted personalization into one place — with a strong emphasis on Swiss data sovereignty. Internative designed and built the product end to end: the UI/UX, the full software platform, and the many integrations that make it work.
The challenge
Modern B2B outreach is fragmented: prospect data lives in one tool, email and tracking in another, AI personalization in a third, and payments and storage somewhere else again. Heysali set out to unify that into a single platform — and to do it in a way that respects Swiss expectations around data residency and sovereignty. That meant building a lot of integrations, well, and choosing AI infrastructure that keeps data in Switzerland.
What we built
We delivered Heysali as a complete product — design and engineering — with a deep set of integrations across data, outreach, AI, payments, and storage.
Multi-channel email outreach
- Gmail integration for email marketing and outreach.
- Outlook integration for email marketing and outreach.
- SMTP support so teams can send from their own infrastructure.
- Email tracking — delivery, open, and engagement status surfaced back into
the platform, so reps know what's landing.
B2B data and buying signals
- Explorium integration — B2B prospect data (an Apollo-style source), plus
buying-signals intelligence to help teams reach accounts at the right moment.
- Cognism integration — a second B2B data source for broader, higher-quality
coverage.
AI-assisted outreach — hosted in Switzerland
The AI layer is where Heysali stands apart. Through Infomaniak's Swiss-hosted LLM infrastructure, we integrated multiple models — including Apertus-70B (Switzerland's own open LLM), Qwen3.5-122B, Kimi-K2.6, and Ministral-3-14B — and used them to power features like AI mail template generation. The result: AI-personalized outreach that keeps data on Swiss infrastructure rather than sending it abroad. This is exactly the kind of governed, model-flexible AI integration we describe in our AI Integration Services and MCP & tool development work.
Payments and storage
- Payrexx integration for payments — a Swiss payment provider that fits the
product's local-first posture.
- MinIO for file storage — a self-hostable, S3-compatible object store that
keeps Heysali in control of its own data.
Why it matters
Heysali shows what a well-integrated, sovereignty-aware platform looks like: prospect data, multi-channel email with real tracking, AI personalization on Swiss-hosted models, and payments and storage chosen to keep control local. The hard part was never any single feature — it was making a dozen integrations work together reliably, behind a clean, usable product.
The result
A single platform where Swiss B2B teams can find the right accounts, reach them across email channels with full tracking, personalize at scale with Swiss-hosted AI, and run the commercial side — payments and data — on infrastructure they trust. Designed and engineered by Internative through our SaaS Factory and AI Studio, backed by our senior İstanbul team.
Build your platform with Internative
If you're building a data-rich, integration-heavy, AI-powered product — with real requirements around sovereignty and control — talk to our team.