Junior Full Stack Developer

Maze Digital builds accounting software integrations, often bridging payment providers and third-party accounting platforms where requirements, data models, and API behaviour vary significantly across vendors.

I joined part-time while also working at Buddy, contributing to integration delivery where speed, correctness, and resilience mattered more than perfect requirements or clean documentation.

The main challenges were building reliable integrations under uncertainty: inconsistent APIs, evolving requirements, edge cases in financial data, and the practical complexity of OAuth flows and webhook-driven sync.

CarbonPay – delivered multiple accounting integrations, including Sage Line 50 bank feed functionality and integrations with platforms such as Expensify, FreshBooks, and QuickBooks.

Mollie Bank Feeds – implemented bank feed integrations targeting Sage Online Accounting and QuickBooks, enabling automated transaction syncing for downstream reconciliation and reporting workflows.

I treated each integration as a reliability problem first: clearly define source-of-truth fields, map vendor-specific concepts into a consistent internal representation, and design the sync process to be repeatable and safe under retries.

For authentication, I implemented OAuth flows with a focus on secure token handling and practical operational behaviour (refresh logic, revocation scenarios, and re-auth UX where needed).

For ongoing data sync, I implemented webhook-driven updates where supported and fallbacks where not, handling partial payloads, vendor quirks, and idempotency to prevent duplicate or inconsistent financial records.

Given limited requirements, I worked closely with leadership and client-side dev teams to confirm expected behaviours early, validate edge cases quickly, and ship incrementally without breaking existing workflows.