← All Case Studies
SaaS Full Stack Security

Vaultbox

Encrypted document storage for SMBs. Built from zero to $500k ARR in year one — with 99.9% uptime across the whole run.

* Client name and identifying details changed to protect confidentiality.

$500k
ARR in year one
99.9%
Uptime since launch
0
Security incidents
Vaultbox encrypted storage

The Problem

Small and mid-sized businesses handle sensitive documents every day — contracts, NDAs, HR files, financial records — and most store them in whatever the team is already using. Google Drive with a shared password. Dropbox Business with no audit trail. Email attachments from 2017.

Vaultbox's founder had spent 8 years in enterprise compliance and watched companies fail audits over document handling they didn't even know was a problem. The thesis: build the security posture of an enterprise document vault at a price point an SMB could actually afford, with an interface that didn't require a dedicated IT admin to operate.

They came to us with a clear product vision, a compliance requirements doc, and no engineering team. The clock was ticking — a key enterprise pilot customer had given them a 4-month window to show a production product or walk.

"We had one shot at this pilot. I needed a team that understood what 'production-ready' actually meant for a security product, not just something that looked finished."

— Founder, Vaultbox

What We Built

End-to-End Encryption Architecture

Every document is encrypted client-side before it leaves the browser using AES-256-GCM, with per-document keys that are themselves encrypted with the user's derived key. Vaultbox's servers never see plaintext — not during upload, not during storage, not during retrieval. We used the WebCrypto API for in-browser operations and a HKDF-based key derivation scheme tied to authentication credentials. The architecture passed a third-party security audit before the pilot started.

Audit Trail and Compliance Layer

Every document access event — view, download, share, edit, delete — is logged to an append-only audit table with user ID, timestamp, IP, and action type. The audit log is tamper-evident via hash chaining and exportable as a signed PDF for compliance reviews. SOC 2 Type I was achieved in month 7 of operations, using the audit trail as the primary evidence artifact.

Role-Based Access and Sharing

Document permissions are modeled as capabilities rather than simple read/write flags — giving teams fine-grained control over who can view, download, re-share, or comment on each document. Time-limited share links with optional password and download restrictions were a feature that came directly from the compliance requirements doc and immediately became the most-used feature after launch.

Full-Stack Subscription and Billing

Stripe integration for per-seat SaaS billing, including trials, plan upgrades, and usage-based overages for storage. The billing dashboard gives admins real-time visibility into storage consumption and seat usage. The self-serve upgrade path was a deliberate design choice — no sales call required to go from free trial to paid.

Next.js TypeScript WebCrypto API PostgreSQL S3 (encrypted) Stripe Prisma Tailwind CSS Vercel Resend

The Results

The pilot customer signed a contract before the 4-month window closed. By month 12, Vaultbox had 87 paying accounts, an NPS of 71, and $500k ARR. The security architecture has had zero breaches or incidents since launch — not a small thing for a product in this category.

$500k
ARR Year 1
87 paying accounts across SMB and mid-market. ACV ranged from $3,600 to $42,000.
99.9%
Uptime
Measured across all production months. Two scheduled maintenance windows, zero unplanned outages.
SOC 2
Type I — Month 7
Clean audit. The audit trail architecture made evidence collection largely automated.
71
NPS at 12 months
Driven primarily by the simplicity of the interface relative to enterprise alternatives.

"We passed our SOC 2 audit in month 7. The auditor said our evidence package was the cleanest they'd seen from a first-time submission. That was entirely down to the architecture NextDay built."

— Founder, Vaultbox

Your product
could be next.

30 minutes. Tell us what you're building.

Book a Dev Call →