Writing
Finance systems, delivery & building AI products — 200 pieces so far
Why Yollardayız Shows the Source of Every Number
Every wait time in Yollardayız is labeled — official feed or traveler report, with its age. Credibility is the moat when the competition is hearsay.
Why I Built Yollardayız
Why I built Yollardayız: countless families drive Europe–Turkey each summer planning border crossings on Facebook hearsay. I built the live-data answer.
Modular vs Monolithic Treasury Management Systems
There is no neutral choice between a modular TMS and an all-in-one suite. What each means, what a core treasury system is, and the trade-offs that decide.
camt.054: The Debit/Credit Notification and When You Need It
What camt.054 is — a notification of debits and credits, not a statement — how it differs from camt.053 and camt.052, and the lump-sum breakdown it exists for.
SAP DMEE: How Payment File Formats Are Built
The DMEE format tree explained — node types, the mapping procedures, tree type PAYM, the FPAY* source structures, and where DMEE sits between F110 and PMW.
SAP EBS Posting Rules and Interpretation Algorithms
The SAP EBS configuration chain — external transaction codes, posting rules, account symbols, posting areas 1 and 2, interpretation algorithms, search strings.
BAI2 File Format: Records, Type Codes and How to Read One
Every BAI2 record explained: the 01–99 hierarchy, balance codes 010/015/040/045, credit vs debit type-code ranges, the funds-type field and control totals.
MT940 Format: The Tags, Line by Line
Every MT940 tag explained: :20:, :25:, :28C:, the :61: statement line subfield by subfield, the bank-specific :86:, and the :62a:/:64:/:65: balances.
pain.002 Status and Reject Codes: Reading the Bank's Reply
How to read a pain.002 status report: group, payment and transaction level, the ACTC/ACCP/ACSC status codes, and reject reasons like AC01, AC04 and AM04.
SAP TRM Product Types and Transaction Types, Explained
How SAP Treasury classifies deals: fixed product categories, configurable product types like 51A and 60A, transaction types, and the layers below.
SAP Treasury Fiori Apps: What Replaces Which Transaction
A verified map of the Fiori apps for SAP Treasury and Cash Management in S/4HANA — F6157 to F2332 — with the classic transaction each replaces or complements.
camt.053 Structure: Reading the Statement Field by Field
The camt.053 statement field by field: GroupHeader to TransactionDetails, OPBD/CLBD balance codes, the Bank Transaction Code, and where bank files diverge.
pain.001 Structure: The Fields That Actually Matter
Inside the pain.001 file: GroupHeader, PaymentInformation and the transaction level — which fields treasury maps, and where bank implementations differ.
MT101 vs MT103 vs MT202: Which SWIFT Message Does What
MT101 is a corporate's payment instruction, MT103 a bank-to-bank customer transfer, MT202 an interbank transfer. How they differ and what replaced them.
SAP Treasury Tables: Where Deals, Flows and Positions Live
The database tables behind SAP Treasury and Risk Management — the VTBFHA deal family, FEBKO/FEBEP, FQM_FLOW and the FI link — verified against SAP Help.
SAP Treasury Transaction Codes: The Ones That Matter
A verified reference of SAP Treasury and Risk Management transaction codes — FTR_CREATE to TPM20 — grouped by working area and checked against SAP Help.
Build vs Buy an AI Feature: Model, API or Off-the-Shelf?
Build your own model, call a hosted API, or buy an off-the-shelf tool? A solo builder's framework for the AI build-vs-buy call — and when each is the right one.
SAP TRM vs a Standalone TMS: Embedded or Best-of-Breed?
Run treasury inside SAP (TRM) or buy a standalone TMS? A vendor-neutral look at the embedded-vs-best-of-breed trade-off, the real drivers, and who each fits.
The Best Treasury Management System: How to Choose
There is no single best TMS — the right one depends on your category. A vendor-neutral guide to the four kinds of TMS, who each fits, and how to decide.
Production AI Observability: Watching What the Model Does
You can't fix what you can't see. How I observe AI features in production — quality, cost, latency, drift and failures — so problems show up as data, not churn.
AI Output Contracts & Failure Handling
A model will return garbage, the wrong shape, or a confident lie. How I design output contracts, validation and fallbacks so the product fails safely.
AI Evaluation & Regression Testing
How I build eval datasets for AI features — cases, scoring, regression gate — so a prompt or model change is judged on evidence, not three examples and hope.
Liquidity Escalation Framework
How to build a liquidity escalation framework — thresholds, tiers, actions and owners — so a liquidity squeeze triggers a plan, not panic.
Cash Forecast Operating Model & Ownership
A cash forecast is a process, not a spreadsheet. Who owns it, who contributes, at what cadence, and how to run the forecast-to-actual loop people trust.