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Curated insights and technical field notes on Architecture.

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Architecture

The broker pattern is older than the agentic-commerce headline

Stripe Shared Payment Tokens are the agentic-commerce headline, but anyone who ran a card tokenization rollout in 2014 recognizes the shape in five seconds. A scoped surrogate credential with a thin stable interface in front and brokered complexity behind is not new. Visa Token Service shipped it twelve years ago, and the architects who see the pattern early build the right systems instead of rebuilding every eighteen months.

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01 / Payments

Commerce architecture

Merchant-of-record decisions, checkout ownership, billing operations, settlement, reconciliation, and risk boundaries.

02 / AI tooling

Practical AI systems

Agentic commerce, multi-agent orchestration, model fine-tuning, runtime governance, and production deployment.

03 / Build notes

From idea to system

The design, architecture, and operating decisions behind Doric Stack products as they move from prototype to public release.

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By Navin Agrawal Architecture 3 min read

ISO 20022's real deadline is a data migration, not a message change

The translator is ready, the mapping is tested, the structured fields are wired - and the project is still not on track, because the customer records are missing structured address data across KYC, core banking, and correspondent files. In November 2026, SWIFT, SEPA, and CHAPS start rejecting unstructured addresses, and most banks are framing the wrong problem.

By Navin Agrawal Architecture 2 min read

Payment platforms have docs. Almost none have a developer experience

Payment integration usually starts with a PDF, a sandbox that takes days to provision, and a support email that answers in 48 hours - and the third email is where patience dies and a competitor gets Googled. I built a self-service workbench to close the distance between what a platform can do and what a developer can figure out alone.