Senior Backend Software Engineer

About the role

Merchants connect to APEXX once and reach the world's payment ecosystem: acquirers, alternative payment methods (APMs), Buy Now, Pay Later (BNPL) providers and network tokenisation. We don't own an acquirer, so our only incentive is the merchant's outcome. We're looking for a Senior Software Engineer in Bengluru to help build and run the core of that platform.

What you'll do

• Own core payment flows end to end: authorisation, capture, refund, void and MIT/recurring across card and APM rails, from design doc to production and beyond
• Evolve our routing and recovery logic: rules-based and data-driven routing, decline cascading
• Build and maintain connectors to acquirers, APMs and BNPL providers: normalise responses, handle API version drift and design for partner outages
• Design for correctness under failure: idempotency, timeouts, ambiguous payment states, asynchronous notifications and webhooks
• Run the platform: join the on-call rotation, define and track SLOs and service dashboards, write runbooks, lead incidents and blameless RCAs

What you need

• Java
• Git
• AWS
• Spring Boot
• CI/CD
• Reconciliation

Good to have

• System design
• Snowflake
• ISO 27001
• PostgreSQL
• Redis
• Terraform