Sr. C++ Developer — Payment Gateway & Platform Engineer

About Datacap Systems, Inc.

Datacap Systems, founded in 1983 in Montgomeryville, PA, is a leader in hardware- and processor-agnostic payment solutions, processing over $140 billion annually across more than 500,000 paypoints and serving 900+ ISV partners. The company has a four-decade legacy of innovation, including pioneering integrated payments technology, EMV capabilities, cloud-managed tools, and direct-to-PIN-pad integration.

Role Overview

We are seeking a motivated C++ Developer to join our gateway engineering team and own the software at the core of our transaction processing platform. You will build and maintain the gateway services and processor connectors that route, authorize, and settle card transactions — including our transaction routing engine and the integrations that connect Datacap to most major payment processors in the US and Canada. You will also help maintain and harden our cloud payment APIs and play a direct role in keeping the entire gateway platform PCI DSS compliant. This is a backend-focused role at the heart of how money moves through Datacap.

Key Responsibilities

Develop and maintain high-performance, high-reliability C++ gateway services and the processor connectors that integrate Datacap with most major payment processors in the US and Canada.

Design, extend, and maintain our transaction routing engine that brokers messages between merchants, gateway services, and processors.

Contribute to and maintain our cloud-hosted payment and tokenization APIs, primarily in C#/.NET.

Help architect, deploy, and operate the Azure infrastructure that runs our gateway — including virtual machines, containerized workloads on Kubernetes (AKS), databases, load balancers, and web application firewalls — with an emphasis on security, high availability, and performance.

Own PCI DSS compliance across our gateway applications and supporting infrastructure — secure coding, network segmentation, key management, encryption, secrets handling, audit logging, and remediation of findings — treating compliance as a first-class engineering requirement, not an afterthought.

Analyze processor specifications and translate complex message formats and certification requirements into correct, well-tested code.

Troubleshoot and debug production transaction issues, including latency, message-format, and connectivity problems against live processors.

Proactively identify reliability, security, and performance improvements and drive them to completion as a strong self-starter.

Required Qualifications

Proficient in C++, with experience building reliable, performance-sensitive backend or systems software.

Working knowledge of C#/.NET (or strong ability to ramp quickly) for cloud API development.

Solid understanding of networking and protocols (TCP/IP, TLS, sockets) and structured/binary message formats.

Hands-on familiarity with Microsoft Azure and cloud infrastructure — virtual machines, AKS/containers, managed databases (e.g., SQL), load balancers, web application firewalls, networking, and CI/CD across multiple environments.

Strong analytical and critical-thinking skills; adept at interpreting and implementing against detailed third-party specifications.

A security-conscious mindset and an appreciation for working in a regulated environment.

Excellent communication and collaboration abilities.

Highly self-motivated, able to independently manage tasks from inception to delivery.

Ideal, But Not Required

Hands-on experience with payment industry standards — card processing, EMV, tokenization, P2PE, key management, and processor certification.

Direct experience integrating with payment processors or acquirers.

Working knowledge of PCI DSS and secure-SDLC practices in a PCI/SOC 2 environment.

Experience with infrastructure-as-code, containerization, web application firewalls, and observability/monitoring tooling.

Cross-platform or mobile experience (Windows, iOS, Android; Swift, Objective-C, Java, Kotlin) — a plus for collaboration with our device/SDK teams, but not a focus of this role.

Experience with API and SDK design.

Why You'll Love Working Here

Join a team at the forefront of payments innovation that is deeply product-focused.

Work on the systems that move billions of dollars a year — your code runs in the critical path of real transactions.

Be an important part of a small, high-impact team where developers are empowered to make meaningful architecture and product decisions.

How to Apply

If you're passionate about building secure, reliable payment infrastructure and thrive on autonomy paired with collaboration, we'd love to hear from you. Please send your resume, a brief note on your experience, and why you're interested in Datacap.

Job Type: Full-time Benefits: 401(k) matching, Health insurance Work Location: In person

Pay: $120,000.00 - $150,000.00 per year

Benefits:

401(k)

401(k) matching

Health insurance

Paid time off

Work Location: In person