API Integration

Connecting a product to a third-party system, with the retry, backfill and reconciliation work priced.

5 categories20 tasks128h - 292h estimated

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Integrations get quoted as "connect A to B" and delivered as retries, backfills and reconciliation. This template prices the whole job in 20 tasks across Discovery, Build, Data Migration, Testing and Launch & Support, so the invisible engineering that makes an integration trustworthy is in the number from the start.

The expensive surprises are predictable: the third-party API that behaves differently than its documentation, the historical data that has to be backfilled without double-writing, the failure modes that only show up under load, and the reconciliation report that proves the two systems agree. Each is a line item here with an hour range, which turns "why is this taking so long" into a scope your client already approved.

One click copies the breakdown into your workspace. Edit it with your team, tighten the ranges to the systems you are actually connecting, and keep the estimate open next to the project as the single document everyone updates together.

What's in this estimate

Discovery

Estimated time (h)

Vendor API review and limits

Read the docs properly. Rate limits, pagination and what the API cannot do.

4.0 - 10.0

Auth model and credential handling

OAuth or keys, rotation, and where the secrets are going to live.

3.0 -  8.0

Field mapping and data contract

Field-by-field mapping between both systems, signed off before build.

6.0 - 16.0

Sandbox access and test accounts

Getting credentials out of the vendor. Frequently the longest lead time here.

2.0 -  6.0
Hours
15.0 - 40.0

Build

Estimated time (h)

Client library and transport layer

HTTP client, serialisation, logging and configuration.

8.0 -  16.0

Authentication and token refresh

Token acquisition, refresh, expiry handling and revocation.

6.0 -  14.0

Data mapping and transformation

The mapping layer both ways, including the fields that do not line up.

12.0 -  30.0

Sync scheduling and queueing

Scheduled and on-demand sync, queued so it survives a slow vendor.

10.0 -  24.0

Webhook receiver and verification

Endpoint, signature verification, replay protection and ordering.

8.0 -  18.0

Retry, backoff and idempotency

The difference between an integration that works and one that pages you.

8.0 -  16.0

Error handling and alerting

Classified failures, a dead letter path and alerts a human will act on.

6.0 -  12.0
Hours
58.0 - 130.0

Data Migration

Estimated time (h)

Historical backfill

Importing existing records, throttled to stay inside the rate limit.

8.0 - 24.0

Reconciliation report

Proving both systems agree, and showing the client where they do not.

6.0 - 12.0
Hours
14.0 - 36.0

Testing

Estimated time (h)

Integration tests against sandbox

Automated coverage of the happy paths against the vendor sandbox.

10.0 - 20.0

Failure and rate-limit scenarios

Timeouts, 429s, partial failures and duplicate delivery.

6.0 - 12.0

End-to-end UAT with the client

Walking the client through real records in their own data.

6.0 - 12.0
Hours
22.0 - 44.0

Launch & Support

Estimated time (h)

Runbook and documentation

How it works, how it fails and what to do at 3am.

4.0 - 10.0

Monitoring dashboard

Sync volumes, failure rates and queue depth, visible without a shell.

4.0 -  8.0

Production cutover

Credentials, first live sync and a rollback plan.

3.0 -  8.0

Post-launch stabilisation

The fortnight after go-live, when the real data arrives.

8.0 - 16.0
Hours
19.0 - 42.0
Tasks

20

Hours

128.0 - 292.0


Make it your estimate

One click copies all 20 tasks into your workspace - then edit the hours with your team to fit the project in front of you.

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