Planning an Integration

Start with the why

Before any code, get clear on what the integration is actually for. What business outcome does it serve, what data must move, and in which direction? An integration built without a sharp goal tends to sprawl, solving problems nobody had while missing the one that mattered.

Write down the concrete requirements: the operations you need, the data involved, the volume expected, and how fresh that data must be. These answers shape every later decision — synchronous or asynchronous, polling or webhooks, full or incremental sync. Spending an hour on requirements up front routinely saves days of rework, because the hard choices become obvious once the purpose is precise. Read the API documentation early at the API docs.

Map the data flow

With the goal clear, sketch how data actually moves. Which system is the source of truth, where does data go, and how is it transformed on the way? Drawing this out exposes assumptions and gaps before they become bugs.

• Direction — one-way or bidirectional, and which side wins on conflict.
• Volume and frequency — a trickle and a flood need different designs.
• Freshness — real-time, near-real-time, or periodic is fine.
• Shape — how the API's data model maps to yours, and where it must be transformed.

These properties determine the patterns you reach for, so settling them early stops you building the wrong architecture and discovering it late. A clear flow diagram is the cheapest design artefact you will produce.

Plan for the hard parts

The easy 80% is the happy path; the hard 20% — failure, security, observability — is what separates an integration that survives production from one that limps. Plan these deliberately rather than bolting them on after something breaks.

Decide how you will handle errors and retries, where credentials live and how they rotate, and what you will log and monitor. Think through the failure modes specific to this integration: what if the API is down, slow, or rate-limiting you; what if data conflicts or arrives twice. Designing for these from the start is far cheaper than retrofitting them during an incident, and it is exactly the part teams most often skip. Treat it as core scope, not polish.

Sequence and define done

Build to reduce risk, not in feature order. Start in the sandbox, prove the riskiest assumption first, and add resilience as you go rather than all at the end.

1. Read-only call in sandbox
2. Core happy path end to end
3. Error handling and retries
4. Logging and monitoring
5. Promote to production

Finally, define what done and healthy mean before you start, so you know when to stop and how you will tell it is working. Concrete success criteria and health signals turn a vague it seems to work into something you can actually verify and operate. An integration without a definition of healthy is one you cannot confidently run.