We build FinTech and blockchain systems that keep balances correct, settle payments reliably and leave a full audit trail. Key management and access controls are designed in from the start, and monitoring gives risk and compliance teams the evidence they need.
What's included
6 capabilities, delivered by one squad. Use what you need now and add more as you grow.
Double-entry bookkeeping where each transaction posts exactly once, and reconciliation that stands up in a dispute.
Connect payment providers, banks and payment rails with retries, routing and real-time monitoring.
Smart contracts designed against a threat model, with code audits, safe upgrades and checks in the build pipeline.
Key management, signing workflows and custody controls that protect keys in day-to-day use.
KYC and AML workflows, risk scoring, policy rules and hooks for your fraud controls.
Event history, approvals, reports and alerts for regulators and internal risk teams.
Our approach
The usual way
Balances live in several systems that disagree, causing disputes and broken reports.
How we do it
One ledger as the single source of truth, where each entry posts once even if a request repeats, with reconciliation evidence for every entry.
The usual way
Key management, custody and access controls added too late.
How we do it
Custody, signing flows and least-privilege access designed in from the start, based on a threat model.
The usual way
No event history, approvals or evidence when regulators and risk teams ask.
How we do it
Policy gates, approvals and a complete event history for every regulated operation.
Architecture
Each layer has a clear job, so the system is easier to secure, test and extend.
Client apps, merchant tools, partner APIs and secure intake for finance operations.
Routing, retries, webhooks and connectors to payment providers and banks, for reliable transactions.
Posting rules, the double-entry ledger and smart contracts, with every change of state recorded as an event.
Approvals, activity records, alerts and reports ready for regulators.
How we deliver
4 phases, each ending with an output you can review.
Define what the ledger covers, your risk limits, the evidence you must produce and how success will be measured in production.
Output: Feasibility blueprint
Build the ledger, payment connectors and duplicate-safe posting, and design for the ways payments fail day to day.
Output: Production ledger baseline
Add key management, signing flows, audits, policy gates and automatic evidence collection for compliance.
Output: Secure control stack
Go live with event history, alerts, approvals and reporting, and keep monitoring risk and drift.
Output: Measurable operations as you grow
Your team
Specialists join your squad for this work, alongside a delivery lead who keeps you updated.
Designs what the ledger covers, its posting rules, reconciliation and risk-control workflows.
Threat-models contracts, builds audit pipelines and plans upgrades so contracts stay safe after launch.
Builds payment provider and bank integrations with retries, routing, webhooks and failure handling.
Runs evidence dashboards, approvals, alerts and day-to-day reporting for risk teams and regulators.
Trust and control
Rules, approvals and evidence are checked before any posting or settlement runs.
Signing workflows, custody patterns and least-privilege access protect keys and funds.
A complete history of every change for regulators, internal audit and risk teams.
You keep full ownership of the code, configuration and documentation we create, with no vendor lock-in.
We pick what fits your product and team, not the other way round.
Results
We fixed a core banking platform's dual-write problem with a transactional outbox, change data capture (CDC) streaming and consumers that safely ignore duplicates. Ledgers and downstream systems now stay in step, with 100% data consistency.
For a regional financial hub, we built a digital currency payment platform that replaces slow correspondent banking with atomic delivery-versus-payment settlement and keys held in hardware security modules. Settlement is now same-day (T+0), and costs fell 98%.
We built a smart contract platform that lets a commercial real estate fund sell fractional ownership to KYC-verified investors and settles trades automatically. It holds $500M in assets under custody.
We built an algorithmic trading platform that connects securely to the user's own brokerage account and runs automated strategies. Paper trading lets users test a strategy first, and a live dashboard shows every trade.
We make one double-entry ledger the source of truth for balances. Posting rules always give the same result for the same input, idempotency keys stop a repeated request posting twice, and every entry carries reconciliation evidence. A full event history lets you rebuild any balance and explain it in a dispute.
We build key management, signing workflows and custody controls using MPC and HSM patterns, with least-privilege access for everyone who can approve a transaction. The design starts from a threat model, so key protection is part of the architecture rather than something added just before launch.
Each payment provider and bank connection has retries, routing and idempotency keys, so a timeout doesn't charge a customer twice. Webhooks are hardened against fakes and replays, failure cases are designed up front, and real-time monitoring flags failed payments as they happen.
We build KYC and AML workflows with risk scoring, policy rules and hooks for your fraud controls, plus case management for reviews. Each check and decision is recorded, so compliance teams can show regulators who was checked, what was found and who approved the outcome.
Every regulated operation leaves a complete event history: what changed, which rules ran, who approved it and when. Logs are tamper-resistant, and evidence dashboards and reports let internal audit, risk teams and regulators review activity without asking engineers to pull the data.
We threat-model each smart contract before writing it, run audits and automated checks in the build pipeline and plan how it can be upgraded safely. After launch, alerts and approval gates cover risky operations, and key management keeps signing authority limited to approved people.
Timing depends on what your ledger must cover, the number of payment providers and banks, and your compliance needs. We start with a controls and architecture review that maps the ledger, your risks and the evidence you must produce, before any build. A scoped project can kick off in 1–2 weeks.
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