You own the operating system. On your cloud.
Most AI vendors rent you agents that live in their cloud. We build the operating system your firm owns, deploy it inside your own AWS account, and run it for you. Your data, your keys, your infrastructure.
ARCHITECTURE FOR NEW AIOS BUILDS. LEAVING IS A DECISION, NOT A NEGOTIATION.
The whole system lives in your account.
For new AIOS builds, we deploy the AI runtime, the encryption keys, and the data storage inside your organization's own AWS account, not ours. Your data never has to leave infrastructure you control.
That is our standard architecture for new tax-firm deployments, and we are completing the migration of earlier client builds onto the same model. The control plane, the part that decides and acts, runs in your cloud, under your account. You are not renting a seat in a platform that happens to hold your data. You hold it. Then we operate it: monitored, maintained, and accountable, with your people in the decision path. Build plus run, not build and walk away.
- WHERE IT RUNS
- Your own AWS account
- WHO OWNS THE DATA
- You, at every layer
- TENANCY
- Isolated, not pooled
- ENCRYPTION
- TLS 1.2+, AES-256 at rest
- OVERSIGHT
- Human in the loop
- OPERATED BY
- Us, after we build it
The perimeter, drawn
Everything inside the box runs in your AWS account. Runtime, keys, and storage provisioned in infrastructure your firm owns.
Model calls run through AWS Bedrock under your keys, inside your perimeter. Nothing trains on your data.
The system is already in your account. Nothing has to be extracted from a vendor when you leave.
Built for firms held to a real compliance bar.
Six things that hold true by architecture, not by promise. We state exactly what we hold and what we inherit, because a vendor overclaiming compliance is a risk we won't be.
Data residency
Your data stays in your cloud region. Our default models run via Anthropic's API or AWS Bedrock so it doesn't have to leave the region you choose.
Single-tenant
Your environment is isolated, not one row in a shared database beside other firms. One tenant: you.
Encrypted at every layer
TLS 1.2+ in transit, AES-256 at rest on AWS-managed keys. Credentials and tokens encrypted at the application layer, never logged.
Human in the loop
The system proposes and drafts; your people approve what matters. Oversight and error handling are part of the build, not an afterthought.
Auditable by design
Because it runs in your account, your own logging, monitoring, and audit tooling see it. A DPA and sub-processor list are available on request.
Honest about certifications
SOC 2, ISO 27001/42001, and HIPAA eligibility are inherited through Anthropic and AWS. Fellowship AI does not itself hold those certifications, and we won't tell you otherwise.
Our IRS §7216 consent process and Written Information Security Program are built to current IRS guidance (Rev. Proc. 2013-14) and are under review by qualified tax counsel. We don't describe them as finalized or attorney-approved until that review is complete. Separately, because new builds run inside your own AWS account, your clients' taxpayer data never has to leave infrastructure you control. If §7216 or WISP compliance is gating your decision, ask us directly and we'll tell you exactly where things stand.
Why multi-tenant SaaS is a liability for a regulated firm.
The loud AI products in tax, accounting, and legal are multi-tenant SaaS. Your data sits in the vendor's cloud, pooled with everyone else's, governed by their controls. For a firm that answers to the IRS, a state board, or a client's security questionnaire, that's the wrong side of every question that matters.
| The question | Multi-tenant AI SaaS | Fellowship AI |
|---|---|---|
| Where does your data live? | In the vendor's cloud, pooled with every other customer. | In your own AWS account, for new builds. It never has to leave infrastructure you control. |
| Who controls data residency? | The vendor picks the region and the terms. | You do. Your cloud, your region, your retention. |
| Tenancy model | One shared system, many clients, one database. | Single-tenant. Your environment is isolated, not shared. |
| Whose audit covers it? | Theirs. You inherit whatever they choose to attest to. | Yours. It runs where your own logging and audit tooling reach. |
| What happens when you leave? | Your data lives in their system until they delete it. | The system is already in your account. Nothing has to be extracted from a vendor. |
| §7216 signed consent before third-party AI | Their processing terms, applied to every tenant the same way. | Handled inside your own environment, built to current IRS guidance, under counsel review. |
| Who runs it day to day? | You, inside their product, on their roadmap. | We do, on the system you own, wired to your real stack. |
Multi-tenant SaaS is the right tool for plenty of jobs. For a firm holding taxpayer data, patient-adjacent records, or a client roster under NDA, owning the system beats renting it.
Too small for a Big Four build. Too regulated for rented SaaS.
There's a real gap in the middle: established firms that need serious AI infrastructure and can't hand their data to a shared platform, but aren't going to fund a seven-figure consulting engagement to get it. That gap is who we build for.
Tax & accounting
Held to IRS §7216 and WISP. Taxpayer data can't sit in someone else's multi-tenant cloud. Our first and most-proven vertical.
Financial services
Client financials, examiner scrutiny, and security questionnaires that a rented tool can't answer on your behalf.
Professional services
Firms under client NDAs and confidentiality duties that make data ownership a condition of the engagement, not a nice-to-have.
Regulated operators
Established businesses with compliance obligations that outgrew manual work but can't trade control for convenience.
Own the system that runs your firm.
Start with a discovery call. We map how your firm operates, show you what we'd build in your cloud, and tell you exactly where our compliance posture stands before you commit to anything.