API Integrator

About the Role

As an API Integrator at SMPL Core, you’ll bring new game providers into our Casino Games Aggregator, which already delivers 150+ providers and 35,000+ games to operators through a single API. You’ll own each integration from the provider’s documentation and sandbox through to certification and the first production rounds: mapping their wallet protocol onto our internal model, verifying every callback and edge case, and making sure the numbers reconcile. You’ll work day to day with our backend developers and with the provider’s account and integration managers.

What You’ll Do

• Study provider API documentation (REST/JSON, seamless wallet or transfer wallet), identify gaps and ambiguities, and agree on them with the provider before development starts
• Map the provider’s round and transaction lifecycle (bet, win, rollback, refund, bonus and free-spin payouts) onto the aggregator’s wallet model and write a technical integration spec for the backend team
• Set up and maintain the provider sandbox: test accounts, currencies, game lists, callback URLs, HMAC keys, and IP whitelisting
• Verify authentication and signatures, idempotency of duplicate callbacks, timeout and retry behaviour, and correct handling of out-of-order or late transactions
• Write and execute test cases covering the happy path, rollback and refund scenarios, disconnects mid-round, currency and precision handling, and bonus/free-spin flows
• Debug staging and production issues from application logs and callback payloads, isolate whether the fault is on our side or the provider’s, and hand the developer a reproducible case
• Reconcile transactions between our ledger and provider reports, investigate discrepancies with SQL, and drive them to resolution
• Keep integration documentation current: provider-specific quirks, configuration parameters, known limitations, provider contacts, and runbooks for the support and account teams

Certification and Go-Live

• Prepare and run certification with the provider and with test laboratories such as GLI and iTech Labs, and collect the evidence regulators require per jurisdiction
• Coordinate go-live with backend developers and provider account managers, including game catalogue import and launch of games for operators
• Support providers and operators during UAT, and run regression checks when a provider releases API changes
• Track the status of every integration in progress and report blockers, next steps, and expected launch dates

Why SMPL Core?

• A chance to join a company with a strong brand and long-established reputation in the global iGaming industry
• Continuous talent development and accelerated career growth opportunities
• Flexible working hours (start at 8:00, 9:00, or 10:00)
• 20 days of paid vacation and Family Days
• English and Czech language courses fully covered by the company
• Access to a confidential mental health support program (professional psychologists)
• Stable income and long-term cooperation

Requirements

• At least 2 years in iGaming integrations, or in backend development or QA working with third-party APIs
• Solid understanding of HTTP/REST and JSON: status codes, headers, request signing, and error semantics
• Familiarity with wallet integration models used in iGaming (seamless wallet and transfer wallet) and the round/transaction lifecycle, including rollback and refund
• Hands-on experience with Postman, cURL, or similar tools and with provider sandbox environments
• SQL sufficient for transaction investigations and reconciliation queries against production data
• Ability to read application logs and callback payloads and trace a failed round end to end
• Experience writing and executing test cases against third-party APIs
• Basic scripting in Python, JavaScript, or Bash for automating checks and reconciliation is a plus
• Experience with provider certification or test-lab requirements (GLI, iTech Labs) is a plus
• English at B2 level or higher for daily written and spoken communication with providers
• Attention to detail and the discipline to keep several integrations moving in parallel
• Comfortable working with backend developers and provider account managers, and able to explain technical issues to a non-technical audience