The umbrella page for money-first businesses: if you lend, move, manage or account for other people’s money, I build your systems on the same double-entry, audit-proof core — specialised per vertical.
Which vertical are you?
Lending — origination, servicing, collections, co-lending splits, and classification you can defend to an inspector. Payments — gateway integrations, payouts, webhook reliability and the reconciliation layer that keeps your books agreeing with the bank. NBFC operations — the regulated back office for lenders who have outgrown Excel but should not be paying enterprise licence fees. Wealth — portfolio accounting, custodian reconciliation, fee computation and client reporting that ties. Marketplaces — seller ledgers, commission engines and settlement cycles that sellers trust. Insurance — renewal books and commission reconciliation across insurers. Subscriptions — recurring billing on a ledger, so MRR is auditable.
What is common across all of them?
Three disciplines, and they are the reason one architect can serve verticals this different.
Immutable history. Auditors, regulators and your own future engineers believe append-only records and nothing else. A system where corrections overwrite history cannot explain itself, and explaining itself is the entire job when someone asks.
Double-entry structure. Every movement has a from and a to, and imbalance is made structurally impossible rather than policed by review. This is a five-hundred-year-old idea that survives because it assumes people make mistakes — the engineer’s version is here.
Daily reconciliation. External truth — bank statements, settlement files, custodian reports — matched against internal records every day, with exceptions queued and reasoned. Errors caught young are cheap; errors caught at month-end have already bred dependents in reports and decisions.
Why the regulator is not the point
Every one of these verticals has a different supervisor — RBI, SEBI, IRDAI, DFSA, FCA — with different vocabulary, different returns and different inspection styles. It is tempting to organise systems around whichever one applies to you.
That is backwards. Underneath the differences, every regulator is asking the same question: can your systems prove what happened? Not “do you have a policy”, not “did you intend well” — can you produce, on demand, the complete history of an account, a transaction, a fee, a classification decision, with the evidence attached.
Build for that question and the specific regime becomes a reporting layer. Build for the reporting layer and you will rebuild every time a format changes, while still being unable to answer the underlying question. The fourteen architecture teardowns show this pattern holding across companies operating under wildly different regimes at very different scales: the ones with defensible books built the same way, whatever their regulator called it.
Where to start if you are unsure
The money path. Trace one unit of value from the moment it enters your business to the moment it leaves or settles: what records it, what could double-count it, what reconciles it, and who could change it without leaving a trace. That walk takes an hour and it locates every real problem you have.
If it is uncomfortable, that discomfort is the honest starting point — and it is the same walk I do on day one of any diligence engagement or fractional CTO month.
Related reading
/services/fintech — the practice · /blog/why-your-ledger-drifts — the failure mode · /products/ledger-platform — the deployable core · /work/ledger-rebuild — the archetype engagement
Not sure which page is yours?
Describe how money moves through your business and I will route you honestly — including to nobody, if that is the right answer. /contact.
Questions I actually get
Which of these pages should I actually be reading?
Describe how money moves through your business and the answer is usually obvious within a sentence. If you lend, start with lending. If you move other people's money, payments. If you hold value on someone's behalf, marketplaces or subscriptions. If you manage it for them, wealth. When it genuinely spans two, the architecture is the same anyway.
Is the underlying system really the same across all these verticals?
The core is: immutable events, double-entry postings, balances as projections, daily reconciliation. What differs is the vocabulary, the regulator and the reports. That is why one architect can serve all of them — the hard part is the same problem wearing different costumes.
Do you work with regulated entities?
Yes — NBFCs, brokers, intermediaries, and companies operating under RBI, SEBI, IRDAI, DFSA or FCA oversight. I build the systems evidence those regimes expect; your compliance owner and counsel own the filings and the interpretation.
What if we are pre-regulatory — still building?
Then this is the cheapest moment in your company's life to get the money path right, because retrofitting a ledger under live volume is surgery. The pre-Series-A review exists for exactly this conversation.
Do you take equity or revenue-share instead of fees?
No — fixed scope and fixed fees. An advisor with a stake in the outcome is not neutral about the architecture, and neutrality is most of what you are buying from an independent.
How do you handle audit and diligence requests?
By building systems where the evidence is a by-product of operating rather than a project. When diligence arrives, the answers are queries — which is also what makes the diligence go quickly.