Senior Backend Engineer, Payments Platform Architect

Tillster; Los Angeles (CA); Hybrid; USD 150,000 - 175,000; Full time

Benefits offered by this job

Health benefits

Paid holidays (10)

Vacation/PTO 15 days first year

401(k) Plan

Education assistance (Udemy)

Job summary

Tillster in San Diego is seeking a Senior Software Engineer – Back End to own and evolve the payment-terminal platform behind our kiosks, including 40+ integrations and a modular SDK.

The role is hybrid, based in San Diego, requiring hands-on design and implementation across low-level protocols, PCI-DSS considerations, and multi-party payment flows.

You will mentor engineers, drive technical direction, and work with security teams to minimize PCI scope and ensure robust reconciliation.

Qualifications

• 6+ years in backend engineering with Java and Spring.
• Experience designing extensible plugin/SPI architectures.
• Hands-on with serial/USB protocols and payment integrations.

Responsibilities

• Own payments domain end-to-end on kiosk platform: authorize, capture, void, refund, settlement.
• Architect a pluggable payment SDK and contract lifecycle.
• Design terminal abstraction across integrated/semi-integrated/cloud processors and cash devices.
• Build integration test harness for validating new integrations before hardware.
• Define patterns for money movement: idempotency, reconciliation, and fault tolerance.
• Reduce PCI-DSS scope with tokenization and TLS/mTLS practices.
• Lead design reviews and mentor engineers.

Skills

Java

Distributed systems design

Plugin / SPI architecture

Low-level device protocol

Payment integration experience

PCI-DSS knowledge

Technical leadership

Tools

Spring

Maven

OSGi / ServiceLoader

Serial/USB protocols

Job description

Tillster in San Diego is seeking a Senior Software Engineer – Back End to own and evolve the payment-terminal platform behind our kiosks, including 40+ integrations and a modular SDK.

The role is hybrid, based in San Diego, requiring hands-on design and implementation across low-level protocols, PCI-DSS considerations, and multi-party payment flows.

You will mentor engineers, drive technical direction, and work with security teams to minimize PCI scope and ensure robust reconciliation.