API Development & Integrations for E-commerce & D2C
Orders in the store, stock in a spreadsheet, dispatch in the courier's dashboard, and three of them disagree.
API development and integration work connects separate systems so data moves between them automatically. For a D2C or e-commerce brand, the work is judged on contribution margin per order, after shipping, returns and ad cost. Order, inventory and fulfilment synced both ways, with exceptions raised rather than silently absorbed.
What is costing you money today
Orders in the store, stock in a spreadsheet, dispatch in the courier's dashboard, and three of them disagree.
Optimising ads to purchase events reported by a browser pixel that ad blockers and iOS have already broken, then scaling on numbers that overstate revenue.
What changes once this is in place
Order, inventory and fulfilment synced both ways, with exceptions raised rather than silently absorbed.
How e-commerce & d2c actually buys
Minutes to days for impulse categories, weeks for considered ones — and heavily concentrated into a few sale periods a year.
- The unit of value
- contribution margin per order, after shipping, returns and ad cost
- The common mistake
- Optimising ads to purchase events reported by a browser pixel that ad blockers and iOS have already broken, then scaling on numbers that overstate revenue.
- What we do instead
- Server-side tracking with order value and margin passed through, reconciled weekly against what the payment gateway actually settled.
What it has to talk to
A build for a D2C or e-commerce brand is mostly integration work. These are the systems we expect to exchange data with:
- Shopify / WooCommerce
- Payment gateway
- Logistics & courier APIs
- Meta CAPI & Google Enhanced Conversions
- Klaviyo / WhatsApp
The words your buyers actually use
Generic service copy loses to copy written in the vocabulary of the vertical. These are the terms that carry intent here, and the ones the pages we build are structured around:
- cash on delivery
- free shipping threshold
- return policy
- size guide
- abandoned cart
- average order value
The rules this sits under
India's Legal Metrology rules on displayed pricing and country of origin; consumer protection rules on returns; FTC substantiation for claims in the US; VAT display requirements in the UAE.
What you get
- Integration map — Every system, what it owns, what it needs, and where the truth lives for each entity. Most integration projects should start by deciding which system owns the customer record.
- API design — Resources, versioning, authentication, pagination, rate limits and error shapes, agreed before implementation.
- Implementation — REST or GraphQL endpoints in TypeScript, with validation at the boundary and types generated from the schema.
- Third-party integrations — CRM, ERP, Tally, payment gateways, WhatsApp Business API, courier and ad platform APIs — with credentials handled properly.
- Webhook handling — Signature verification, idempotency keys, a queue, retries with backoff and a dead-letter store you can replay from.
- Sync and reconciliation — Scheduled reconciliation that compares both systems and reports differences, because event-driven sync alone always drifts eventually.
- Monitoring and alerting — Failure alerts to the channel your team actually reads, with enough context to act rather than just to worry.
- Documentation — API reference, an integration runbook, and a page describing what to do when each integration fails — written for whoever is on duty, not for us.