Staff Software Engineer, Financial Platform - Issuing

Block•Bay Area, CA, United States of America, CA

10h•$263,600 - $395,400•Remote

About The Position

The Financial Platform Issuing team at Block owns the card issuing platform that serves every Block brand, powering Cash App Card, the fourth-largest debit card program in the US, alongside Square Card and new card programs. This team manages the full lifecycle of a card, including issuance, fulfillment, activation, real-time transaction authorization and processing, digital wallet provisioning, 3-D Secure authentication, clearing and settlement, and disputes. The systems operate in milliseconds, 24/7, in partnership with card networks and bank partners. As a Staff Software Engineer on the Issuing server engineering team, you will bring deep card-network expertise to complex technical challenges. You will collaborate with technical leads and cross-functional teams, focusing on the intersection of the platform and card networks, including specifications, protocols, certification, mandates, conformance, and production behavior. This is a hands-on role involving building systems and tooling, debugging at the message level, and translating network expertise into reusable capabilities for other engineers. You will also engage directly with card networks to understand their requirements and influence outcomes for Block.

Requirements

Deep, current expertise with at least one major card network, ideally Visa, including direct connectivity, ISO 8583, authorization and clearing flows, stand-in processing, specifications, certification, and mandate cycles.
Personally built, certified, or operated a live direct network connection — not only integrated through a processor.
Experience working directly with card networks to land concrete outcomes, such as rulings, exceptions, extensions, configuration changes, defect fixes, or certification outcomes.
Strong hands-on software engineering experience building and operating highly reliable financial or payments systems at scale.
A track record of leading technically complex, ambiguous work across team boundaries and influencing technical direction beyond your immediate area of ownership.
Experience creating durable technical leverage — frameworks, standards, tooling, architecture, or practices that other engineers and teams adopt.
Broad understanding of the card lifecycle, with depth in areas such as issuance and fulfillment, provisioning and activation, authorization, ledgering, clearing and settlement, reconciliation, disputes, or fraud.
Working knowledge of Mastercard and American Express, alongside deep expertise in at least one major network.
Fluency with AI-assisted engineering workflows and sound judgment in evaluating and applying AI-generated output.
Willingness to participate in an on-call rotation for critical financial systems.

Responsibilities

Be a deep technical expert on global card networks, helping Issuing teams interpret network specifications, message flows, certification requirements, mandates, and production behavior — and working directly with the networks to influence requirements, resolve ambiguity, and secure outcomes that matter for Block.
Lead complex, ambiguous engineering problems at the network boundary that span multiple teams, systems, or domains.
Partner with technical leads, program DRIs, and senior stakeholders to shape solutions where card-network requirements intersect with Block's issuing platform.
Stay deeply hands-on: write production code, build certification and conformance tooling, analyze network messages, review designs and code, and debug issues down to the protocol and field level.
Drive network certification and mandatory release cycles end to end, and translate network requirements into clear, pragmatic engineering decisions.
Establish shared frameworks, standards, tooling, and practices that make network expertise durable and enable teams to operate independently.
Raise the technical capability of engineers around you through design guidance, code reviews, mentorship, documentation, and clear technical judgment.
Apply AI-powered tools throughout the engineering lifecycle to improve velocity and quality, and help establish effective patterns for broader team use.
Share operational ownership of critical financial systems through on-call, incident response, and continuous improvements to reliability and correctness.