Connect
AI acts with each person's own permissions
Managed connectors let employees' AI read and act in HR, finance, IT and CRM systems as the person using it, scoped to what that person can already see and do.
About StackOne
StackOne is the Tool Gateway for successful AI rollouts.
Rolling AI out to every team means letting it act in the business systems people work in. StackOne is the tool layer that makes that rollout safe to approve: each person's AI acts with their own permissions, under tool policies IT sets once, with PII redaction, prompt-injection defense and a full audit record on every action. Managed connectors and tool discovery carry the rollout across every system you run.
Our mission
Make it safe to connect AI to all enterprise systems.
Why StackOne exists
Organizations are giving AI to every team. A rollout works when that AI can act in the systems people work in, under the permissions and controls IT already owns.
Secure
IT sets the rules once, for every team
Tool policies decide which tools, fields and values AI can use. PII is redacted from tool calls and logs, Defender screens what the AI reads for prompt injection, and every action is logged for audit.
Optimize
AI gets only the tools it needs
Tool discovery surfaces only the relevant tools for each request, so context stays lean as you connect more systems.
AI security research
Our AI security research, built into StackOne.
StackOne's AI research team studies the risks that come with letting agents act in business systems, starting with prompt injection hidden in the data agents read.
That work ships as Defender, our open-source prompt-injection library, and runs inside every tool call on StackOne.
See how Defender works- Open source Defender is free for any team to use and inspect
- <4ms To scan data before an agent reads it
- 88.7% Detection accuracy on prompt injection
The team
We have built software for enterprise and regulated companies.
Romain and Guillaume have worked together for more than ten years across several SaaS companies.
They started StackOne so companies can give AI to every employee with the security and governance IT needs to approve it. The team comes from banks, payments and enterprise software companies, where every action has to be secure and auditable.
Where the team worked before StackOne
Financial services and telecom
-
-
-
-
Vodafone
Enterprise software
-
-
-
-
-
Contentsquare
Integration platforms
StackOne at a glance
- What it is
- The Tool Gateway for successful AI rollouts
- Founders
- Romain Sestier (CEO) and Guillaume Lebedel (CTO)
- Launched
- 2023
- Funding
- $24M raised, including a $20M Series A, backed by GV and Workday Ventures
- Where we work
- Headquartered in London and San Francisco
- Security
- SOC 2 Type II · HIPAA · GDPR · CCPA
- Coverage
- 590+ connectors and 36,000+ actions
- Press
- Press and media
How we got here
-
2023
Launched out of stealth.
Investment from the co-founder of GitHub.
$3.6M seed round, led by Episode 1, with participation from Playfair and Portfolio Ventures.
-
2024
Launched 100+ integrations across six categories.
Customers on three continents.
-
2025
$20M Series A led by GV, with Workday Ventures and XTX Ventures.
Launched native MCP support.
-
2026
Feb Defender, open-source prompt-injection defense.
Mar SAML SSO, followed by SCIM directory sync.
Sep Launched the Tool Gateway for successful AI rollouts.
Oct Tool Policies: control which tools, fields and values each agent can use, with PII redaction for tool calls and logs.
Customer stories
- A US medical research organization connected nine business systems to its AI agents in under two weeks.
- TYME Technologies grew outbound about 10x with an always-on BD agent.
- Drata deployed 100+ integrations for user access reviews.
Backed by
$24M raised from funds and operators who build and buy enterprise AI.
Funds
Founders and operators from
FAQ
Questions about StackOne.
The company, the team and how we work.
Roll AI out to every system you own.
Start with the connectors you need today, and add governance your security team can approve.