Industries
Payment systems where the failure paths get as much attention as the happy path, because that is where the money actually goes missing.
Short answer
Fintech and MFS software covers payment acceptance, wallet and card integration, settlement and reconciliation. BetterSoftZ builds these for Bangladeshi fintechs and payment-led products, integrating bKash, Nagad, Upay, SSLCOMMERZ, aamarPay and ShurjoPay including refunds, duplicate-payment protection, failed callbacks and end-of-day reconciliation.
Providers time out, retry, and occasionally deliver the same callback twice. A system that assumes one clean notification per transaction will eventually double-credit someone, and finding it afterwards is painful.
Your ledger and the provider statement have to agree every day. Differences need to be surfaced automatically with enough context to resolve them, not discovered at month-end.
Retries are normal. Every operation that moves value must be safe to repeat, keyed so the second attempt returns the first result rather than performing the action again.
Transaction limits, verification tiers and provider rules change on their timetable, not yours. They belong in configuration with an audit trail, not hard-coded in a release.
Charging a customer once, successfully, on a good connection is straightforward. The engineering effort belongs in what happens when the network drops between the charge and the confirmation, when a provider retries a callback four times, when a customer taps pay twice, and when a refund is issued for an order that was partly delivered.
Payment flows are tested in provider sandboxes against scripted failures: timeouts, duplicate callbacks, partial refunds, settlement mismatches and provider outages. If a failure mode has not been exercised before launch, it will be exercised in production instead.
Systems built around your process, not around a template.
Read moreAndroid-first apps tuned for real Bangladeshi networks and devices.
Read moreRegression suites that catch breakage before your users do.
Read morebKash, Nagad, Upay, SSLCOMMERZ, aamarPay and ShurjoPay on the local side, plus international gateways for cross-border collection. The integration work that matters is rarely the initial charge call — it is refunds, partial reversals and reconciliation.
Idempotency keys on every value-moving operation, deduplication on incoming callbacks, and a ledger that records intent separately from confirmation so a repeated callback settles against the original entry instead of creating a new one.
Automated daily matching between your ledger and each provider statement, with unmatched items queued for review with transaction context attached. The goal is a short exception list every morning, not a monthly investigation.
Yes, on double-entry principles with immutable postings and balances derived from entries rather than stored and updated. That design is slower to build and far cheaper to audit, which is the right trade in this sector.
If your rules and realities are unusual, that is the conversation worth having first.
