Software for finance, built to the bar an examiner actually applies.
Regulator-grade SDLC, hash-chained audit trails, and integrations with core banking and trading platforms (FIS, Fiserv, Jack Henry, Bloomberg, Murex) that survive end-of-day reconciliation.
Generalist shops ship financial software that fails its first real audit.
The pattern is consistent. A non-FS firm ships a working app for a bank, broker-dealer, or asset manager. It passes UAT. Then internal audit asks for the change control evidence, the immutable log, and the restore drill results — and there's a six-month remediation project. The team conflates SOC 2 Type II with regulator readiness, treats the database as the system of record instead of an event ledger, and discovers during the first reconciliation break that the upstream core platform sent the same trade twice. The remediation usually costs more than the original build.
- ▸ Audit logs stored in the same Postgres instance as the data they're auditing — trivially tamperable from a single compromised credential.
- ▸ Deploys performed by the same engineer who wrote the code, with no signed artifacts or separation-of-duties evidence for SOX ITGC.
- ▸ Integrations with FIS, Fiserv, or Bloomberg built without idempotency keys, so a replay during failover double-books transactions.
- ▸ RTO/RPO numbers committed in an MSA without a single real restore drill to confirm they're physically achievable.
Build the SDLC the examiner expects, then write the code.
- STEP-01
Map the regulatory surface first
Before a single ticket is written we enumerate which rules touch the system: SOX ITGC, FFIEC, FINRA 4511, SEC 17a-4, GLBA, NYDFS 500, PCI if cards are in scope. That list drives retention windows, evidence capture, and approval flow — not the other way around.
- STEP-02
Pin the audit trail to the data model
Every state-changing event goes through an append-only event log with hash chaining and WORM-compliant storage (S3 Object Lock or equivalent). The ledger is the source of truth; read models are projections. Auditors get cryptographic proof of non-tampering, not screenshots from a Splunk dashboard.
- STEP-03
Wire to core systems with idempotency and reconciliation
Integrations with FIS, Fiserv, Jack Henry, Bloomberg, Murex, or internal trading engines use idempotency keys, end-of-day reconciliation jobs, and out-of-band breaks queues. We assume the upstream will replay, drop, or reorder messages — because it will.
- STEP-04
Ship with four-eyes change control
Production deploys require signed commits, mandatory peer review, separation of developer and deployer identities, and immutable CI artifacts. Change tickets in Jira or ServiceNow are linked to commits and deploys automatically so SOC 2 and SOX evidence is generated, not gathered.
- STEP-05
Set reliability targets the business actually needs
Trading windows and settlement cutoffs make 99.9% useless if the 0.1% lands at 3:55pm ET. We define SLOs against business calendars, run game days against failover paths, and measure RTO/RPO with real restore drills — not tabletop exercises.
// Append-only event ledger with hash chaining.
// Every write is verifiable end-to-end; tampering is detectable.
import { createHash } from 'crypto';
type LedgerEvent = {
seq: bigint;
occurredAt: string; // ISO-8601, UTC, from trusted clock
actor: string; // authenticated principal, not a service account alias
action: string; // e.g. 'wire.approved', 'trade.allocated'
payload: Record<string, unknown>;
prevHash: string; // hash of previous event
hash: string; // sha256(prevHash || canonical(event))
};
export function appendEvent(
prev: LedgerEvent | null,
partial: Omit<LedgerEvent, 'seq' | 'prevHash' | 'hash'>,
): LedgerEvent {
const seq = (prev?.seq ?? 0n) + 1n;
const prevHash = prev?.hash ?? '0'.repeat(64);
const canonical = JSON.stringify({ seq: seq.toString(), ...partial, prevHash });
const hash = createHash('sha256').update(canonical).digest('hex');
return { seq, prevHash, hash, ...partial };
}
// Storage layer writes to S3 with Object Lock (COMPLIANCE mode)
// + Postgres projection for query. The bucket, not the DB, is the system of record.Hash-chained, WORM-backed event ledger — the pattern an examiner can verify in minutes and that survives a compromised database.
Field FAQ.
→ What's the difference between SOC 2 compliant and actually-meets-the-bar engineering?
SOC 2 is a hygiene attestation — it proves you have controls and follow them. It does not prove the controls are sufficient for a regulated workload. A SOC 2 Type II report can coexist with a system that has no immutable audit trail, no separation of duties on deploys, and a 6-hour RTO for a platform that settles trades. We design for the underlying regulation (FFIEC, SOX ITGC, FINRA, NYDFS 500) and treat SOC 2 as a byproduct, not the goal.
→ Can you integrate with our core banking or trading platform?
Yes. We've worked against FIS, Fiserv DNA, Jack Henry SilverLake, Finastra, Bloomberg BLPAPI, Refinitiv, Murex, Calypso, and a long list of internal OMS/EMS systems. The integration patterns are similar even when the protocols aren't: idempotent writes, sequence-number tracking, a breaks queue for unreconciled messages, and a daily reconciliation job that compares our ledger against the upstream's end-of-day extract. We assume the upstream is the system of record and design accordingly.
→ How do you handle change management for regulated environments?
Every commit is signed. Every PR requires review from someone who didn't author it. CI builds produce immutable, signed artifacts. Deploys are performed by a separate identity from the developer, and the deploy pipeline writes a change record back to Jira or ServiceNow with the linked commits, the approver, the artifact hash, and the deploy timestamp. SOX ITGC and SOC 2 CC8 evidence is generated continuously rather than reconstructed from Slack scrollback the week before an audit.
→ What reliability targets do you design to?
It depends on the workload and business calendar, not a generic 'three nines.' For a payments platform with a 5pm ET ACH cutoff, the SLO is framed around availability during the cutoff window, time-to-recover during it, and RPO measured in seconds. For an internal CRM, 99.5% with a 1-hour RTO is fine. We refuse to commit to a number until we understand the cost of missing it. Then we run actual restore drills quarterly and publish the measurements.
→ Are you SDVOSB certified and can you work on federal financial systems?
Yes. VooStack is SDVOSB-certified through SBA's VetCert and eligible for set-aside contracts. We've worked on systems touching Treasury, FDIC-adjacent reporting, and federal financial management modernization. We're comfortable with FedRAMP boundary requirements, FISMA Moderate controls, and the reality that GovCloud deployments have a different cost model and feature lag than commercial AWS. We can sub or prime depending on the vehicle.
→ How long to stand up a regulator-ready greenfield system?
A realistic minimum for a production-grade, audit-defensible system is 12 to 16 weeks, not 4. That timeline includes the threat model, the control mapping, the SDLC scaffolding (signed commits, immutable artifacts, change records, evidence pipelines), the immutable ledger, the first integration, and a real DR test. Anyone quoting four weeks is shipping a prototype and calling it production. We'll tell you that on the first call.
→ Do you do staff augmentation or only fixed-scope projects?
Both. For financial services clients we often start with a small fixed-scope engagement — typically a control gap assessment or a single integration — to establish trust, then transition to embedded senior engineers working alongside your team. Our augmentation engineers are W-2, US-based, background-checked, and have shipped regulated systems before. We don't bench-flip junior staff into FS engagements; the regulatory cost of a mistake is too high.
→ How do you handle PII and PCI data in the audit trail?
The hash-chained ledger stores references and tokens, not raw PAN or full SSNs. Sensitive fields live in a separate encrypted store with field-level keys managed in KMS or HSM, and the ledger records the token plus a hash of the cleartext for verification. This keeps PCI scope tight, lets us prove non-repudiation without storing regulated data in long-retention WORM buckets, and survives a right-to-be-forgotten request without breaking the chain.
→ What happens when an examiner or internal auditor shows up?
You hand them read-only access to the evidence portal. Change records, deploy logs, access reviews, the ledger verification tool, restore drill results, and the control matrix are all queryable. In practice, audits that used to consume two engineers for three weeks consume one engineer for two days. That's the actual ROI of building the SDLC correctly — not a faster feature shipped, but an audit cycle that doesn't derail a quarter of engineering.
Continue recon.
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REL-02Case studies
How we've shipped regulated systems and core platform integrations under audit.
REL-03Engagement packages
Fixed-scope control gap assessments and integration sprints for FS firms.
REL-04Talk to an engineer
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