Engineering, in our words
Postmortems, architecture decisions, and trade-offs from shipping fintech infrastructure, stablecoin payment rails, Web3, and AI systems in production. Honest, occasionally opinionated.
AI/ML·August 18, 2026·8 min readx402 inference billing: pay-per-call routing for AI agents
x402 inference billing meters each AI model call as a USDC micropayment over HTTP. Where pay-per-call routing beats monthly API budgets, and where it does not.
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Fintech·August 11, 2026·9 min readRevenue recognition belongs in the ledger, not in BI
Revenue recognition belongs in your double-entry ledger, not a dashboard query. The accounts, postings and schema that keep deferred revenue audit-ready.
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Fintech·August 5, 2026·11 min readCore banking architecture: event sourcing and CQRS
Core banking architecture with event sourcing and CQRS: what the pattern really buys you, why 61 bounded contexts is a warning sign, and where to draw the line.
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Fintech·July 29, 2026·10 min readUPI anatomy: how real-time payment rails work
How UPI works under the hood: the PSP to NPCI switch to bank flow behind real-time payment rails, why authorization and settlement split, and what breaks.
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Fintech·July 23, 2026·9 min readPayment idempotency: prevent duplicate charges
A practical guide to payment idempotency: design idempotency keys, store responses, and handle retries so a network timeout never double charges a customer.
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Fintech·July 13, 2026·8 min readNanopayments: settling sub-cent agent payments
Nanopayments let agents settle USDC amounts smaller than a network fee. How batching, netting and fractional-cent accounting make sub-cent payments work.
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Fintech·July 6, 2026·7 min readDouble-entry ledgers: the backbone of every fintech app
A double-entry ledger is the 500-year-old accounting model under every fintech app. How it works, the invariants that keep money correct, and why it matters.
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Web3·June 29, 2026·8 min readUpgradeable smart contracts: proxy patterns, trade-offs
How upgradeable smart contracts work, the transparent, UUPS, and diamond proxy patterns, the storage collisions and admin-key risks, and when not to use them.
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Fintech·June 22, 2026·9 min readPayment reconciliation: build an engine that survives
A practical guide to building a payment reconciliation engine that survives partial settlement files, PSP fees, and FX, plus the matching ladder it needs.
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Web3·June 15, 2026·8 min readReal-world asset tokenization: architecture and trade-offs
A field guide to real-world asset tokenization architecture, the token standards, oracle and custody assumptions, and the trade-offs that decide if it works.
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AI/ML·June 10, 2026·7 min readClaude Fable 5 and the long-horizon agent problem
Claude Fable 5 keeps agents coherent for hours, not minutes. What changed, why it matters for fintech automation, and where you still need a human gate.
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AI/ML·June 5, 2026·12 min readAgentic payments: what x402, AP2 and MPP mean for builders
Four agentic payment standards launched in a year. What x402, Google AP2, Stripe MPP, and OpenAI's ACP each do, how they differ, and what you need to build.
Read post- Fintech·April 20, 2026·8 min read
Shipping stablecoin rails without the pain
What we learned launching a USDC-powered remittance corridor, settlement timing, custody trade-offs, and the boring infrastructure that makes it actually work.
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