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API + Integration

API Integration Services

Connecting the systems your business runs on, with idempotent writes, reconciliation and monitoring, so an integration fails loudly instead of silently.

300+
Integrations Built
availability
Delivery Reliability
Idempotent
Every Write
Reconciled
Daily
Abstract network connections representing API integrations
Overview

Integrations fail quietly, which is what makes them dangerous

A broken web page produces a phone call within minutes. A broken integration produces nothing at all: orders stop syncing, inventory drifts, and everyone finds out three weeks later during a stock count. The failure mode is silence, and silence is the hardest thing to monitor.

So the engineering is mostly defensive. Every write carries an idempotency key so a retry cannot double-post. Every integration has a reconciliation job that compares both sides and reports divergence. Every failure lands in a queue a human can inspect rather than disappearing into a log.

None of this is exotic. It is the difference between an integration that works and one that appears to work, and it is what we build by default rather than after the first incident.

Teams that start here often pair it with REST to GraphQL migration, CRM development and custom software development.

A broken integration does not throw an error anyone sees. It just stops, and you find out at month end.

Backend engineer working on server code
The Problem

Why integrations break in ways nobody notices

Four failure modes we find in almost every audit.

Non-Idempotent Writes

A timeout triggers a retry and the order is created twice, because the receiving system had no way to recognise the duplicate.

Fire And Forget

Failures are logged and dropped, so a run that processed sixty of a hundred records looks identical to one that processed all of them.

No Reconciliation

Nothing compares the two systems, so drift accumulates for weeks and is discovered by an accountant rather than an alert.

Brittle Schema Coupling

A vendor adds a field and the parser throws, taking down an integration that had no business caring about that field.

What's Included

What an integration engagement covers

Reliability engineering around the connections your business depends on.

Integration Design

Data flow direction, sources of truth, conflict rules and failure behaviour agreed in writing before code exists.

Idempotent Writes

Every write carries a key derived from the business event, so retries are safe by construction rather than by luck.

Retry And Backoff

Exponential backoff with jitter, a bounded retry scope and a dead-letter queue for anything that cannot be delivered.

Reconciliation

Scheduled comparison of both systems with a divergence report, so drift becomes an alert rather than a discovery.

Schema Tolerance

Parsers that ignore unknown fields and validate only what matters, so a vendor change does not become an outage.

Monitoring

Throughput, latency, error class and queue depth per integration, with alerts on volume dropping as well as on errors.

Our Process

From integration map to production through controlled rollout

Failure paths designed before the happy path is built.

01
Mapping

We document every system, direction, volume and source of truth, including the manual steps people currently do to patch gaps.

02
Contracts

Payload schemas, idempotency strategy, retry policy and reconciliation rules agreed before implementation.

03
Build

Integrations implemented with the failure paths built first, tested against sandbox and production-shaped data.

04
Reconciliation

Comparison jobs and divergence reporting deployed alongside, so correctness is observable from day one.

05
Rollout

Run in parallel with the existing process until reconciliation is clean, then retire the manual steps.

Tech Stack

The stack behind our integrations

Queues, contracts and observability rather than cron jobs and hope.

01
Transport

Queues and webhooks with delivery guarantees, so a receiver being down is a delay rather than a loss.

SQSRabbitMQWebhooksDead-Letter Queues
02
Contracts

Validated payloads with tolerant parsing, so upstream changes are absorbed rather than fatal.

03
Platforms

The systems businesses actually run on, integrated through their real APIs rather than screen scraping.

04
Reliability

Reconciliation and monitoring treated as part of the integration, not as optional extras.

Idempotency KeysReconciliation JobsOpenTelemetryGrafana
In The Field

What this looks like in production

Retail · ERP And E-commerce Integration

Finding the orders that had been silently failing

A retailer synchronised orders between Shopify and NetSuite with a nightly script. It had run for two years and was considered reliable, because nobody had ever received an error from it.

The first reconciliation job we deployed found four hundred orders that had never reached the ERP, spread over eighteen months. The script had been swallowing failures for individual records and completing successfully overall.

We rebuilt it as a queue-driven integration with idempotency keys, a dead-letter queue and daily reconciliation. Nothing about the happy path was more sophisticated; the difference was that failures now had somewhere to go and someone to tell.

400
Silently failed orders found
availability
Delivery reliability since
Daily
Reconciliation reporting
Why Tech Team 4U

What API integration services should include as standard

The engineering that matters in an integration is what happens when the other system is down, slow or wrong. We build that first.

Reconciliation By Default

Every integration ships with a job that compares both sides and reports divergence, because silent drift is the failure mode that effort real money.

Weekly Transparency

A working demo and a written note every Friday covering what shipped, what slipped and what it means for the date. No status theatre.

Staged, Not Risky

Nothing goes live in one jump. We run in parallel or behind a flag until the numbers say it is safe to switch over.

300+
Integrations Built
10+
Years Engineering
availability
Delivery Reliability
0
Silent Failures