About Unlimit

Unlimit is the global financial infrastructure for the borderless agentic economy. Designed to bridge the gap between fragmented local markets and the future of autonomous commerce, Unlimit provides the programmable operating layer for the world’s most ambitious businesses.

Through an integrated technology stack, the platform unifies global payment acceptance, programmable financial accounts, and digital asset rails into a singular financial layer. By mapping hyper-local payment ecosystems directly into its architecture, Unlimit enables businesses to move value and settle transactions instantly across continents.

Built on decades of hard-won regulatory depth and an extensive global license portfolio, the platform provides direct access to a massive global infrastructure. With major hubs in London, San Francisco, Singapore, São Paulo, and Mexico City, Unlimit is building the infrastructure that makes global expansion a matter of code, not geography.

About the role:
We are looking for a senior engineer to become the technical lead of our card processing platform. You will own the SmartVista ecosystem end to end (FrontEnd and BackOffice), set the standards for how processing is built, changed and operated, and lead the work of finding and closing gaps in our processes, configuration and controls.

This is not a pure support or configuration role. We expect you to replace manual work with automation and to put AI to practical use in processing operations: anomaly detection, intelligent alerting, automated root-cause analysis and AI-assisted analysis of scheme specifications and transaction data. The role combines card processing expertise + technical leadership + engineering (backend, scripting, integrations) + automation and AI adoption.

What you will do:

1. Technical leadership and platform ownership

• Own the end-to-end architecture of the processing ecosystem (SmartVista FrontEnd and BackOffice, interfaces, HSM, scheme connectivity) and make architecture and technology-stack decisions.

• Act as the technical lead and senior escalation point for processing engineers; set engineering standards, review solutions.

• Lead major incidents, coordinate the response with internal teams, the vendor and card schemes, and drive post-incident reviews to permanent fixes.

• Manage the relationship with the SmartVista vendor on releases, patches, defects and change
  requests.

2. Process ownership and gap remediation

• Map the current processing processes (authorisation, clearing, settlement, disputes, reconciliation, reporting, release and change management, monitoring and on-call) and identify gaps, single points of failure and manual workarounds.

• Build and run a remediation plan: define owners, deadlines and measurable outcomes, and follow through to closure.

• Introduce and maintain operational standards: runbooks, release and change procedures, incident and problem management, SLAs and KPIs (e.g. availability, approval rate, incident resolution time).

• Make sure scheme mandates and regulatory changes are tracked, assessed and implemented on time, and that the evidence of compliance is documented.

3. Processing development and scheme compliance

• Deliver the technical implementation of new card products and services (acquiring and issuing) for Visa, Mastercard, UnionPay, American Express and other schemes.

• Translate scheme mandates and specifications into technical solutions, and lead certification projects with the schemes.

• Configure and develop SmartVista FrontEnd and BackOffice products, services and business rules.

• Prepare technical requirements for system upgrades; test and install releases and patches with minimal downtime.

• Diagnose complex issues across authorisation, clearing and settlement flows and drive them to root cause.

• Set up and maintain payment system emulators and test environments; take part in go-live and pilot activities.

• Maintain clear technical documentation of the platform and implementation procedures.

4. Monitoring and observability: design, development and implementation

• Design and build an end-to-end monitoring framework for the processing platform, covering infrastructure, applications, interfaces and business metrics.

• Develop and implement real-time monitoring of:

• authorisation flows: approval and decline rates by scheme, BIN, issuer country, merchant, MCC and response code.

• response times, timeouts and stand-in processing.

• scheme, issuer and HSM connectivity and host availability.

• transaction volumes and abnormal spikes or drops.

• Develop and implement monitoring of back-office processes:

• clearing file generation, submission and acknowledgement (Visa, Mastercard and other schemes).

• incoming scheme files and reports, settlement positions and reconciliation breaks.

• end-of-day and batch jobs, interchange and fee calculation, chargeback and dispute deadlines.

• Monitor scheme compliance indicators (e.g. decline-code usage, data-integrity edits, excessive retries, fraud and dispute ratios) to catch issues before they become scheme non-compliance or fines.

• Define thresholds, alerting rules and escalation paths; integrate alerts with on-call, incident management and messaging tools.

• Build operational dashboards for engineering, operations and management, and define the related KPIs and SLAs.

• Develop health checks, synthetic test transactions and log-based monitoring for SmartVista components.

• Continuously tune monitoring to reduce false alerts, and turn incident findings into new checks and controls.

5. Automation and AI

• Identify manual and repetitive processes and automate them, including:

• reconciliation and settlement.

• scheme file exchange and report submission.

• testing, regression and release management.

• monitoring and alerting.

• Build CI/CD pipelines and automated deployment for processing components and configuration.

• Design and deliver AI-driven solutions for processing operations, for example:

• anomaly detection on transaction flows, decline patterns and fraud signals.

• intelligent alerting that reduces noise and escalates what matters.

• automated root-cause analysis of declines and incidents

• AI assistants or agents that analyse scheme specifications, mandates and authorisation messages and flag deviations.

• Introduce test automation and regression frameworks for scheme messages and processing flows.

• Promote the safe use of AI tools across the team, with appropriate controls for data security, PCI DSS and human oversight of changes to production.

What you bring:

• 6+ years of hands-on experience in card processing, covering the full transaction lifecycle: authorisation, clearing, settlement, chargebacks and reconciliation.

• At least 2 years in a senior, lead or architect role, with a track record of owning a processing platform and leading engineers, directly or as a technical lead.

• Strong practical experience with SmartVista (FrontEnd and/or BackOffice); deep experience with acomparable platform (e.g. Way4, TranzWare) may be considered.

• Proven experience of improving processes: finding operational gaps, designing controls and delivering a remediation plan to completion.

• Certification experience with Visa and Mastercard and the ability to read and apply scheme specifications and rules (ISO 8583, Visa Base I/II, Mastercard IPM/CIS).

• Hands-on automation skills: Python, SQL/PL/SQL, Bash; experience with CI/CD tools (e.g. GitLab CI, Jenkins), test automation and API testing (e.g. Postman).

• Practical experience applying AI or ML in production work, such as anomaly detection, LLM-based tools or agents, or AI-assisted analysis and coding, and a clear view of their limits and risks.

• Working knowledge of Oracle DB, WebLogic, Linux, REST/SOAP web services and HTTP.

• Experience with scheme tools: Visa Edit Package, VCX, Mastercard File Express (MFE) and scheme test tools and emulators (e.g. Mastercard MAX, Visa test systems).

• Good understanding of e-commerce and digital payments: EMV 3-D Secure, tokenisation (VTS/MDES), Apple Pay / Google Pay, recurring payments, AVS.

• Knowledge of card technologies and security: EMV, contactless, HSM (Thales), key management, PCI DSS.

• Experience with release and change management in a 24/7 production environment.

• Fluent English (B2+) for daily communication with card schemes, vendors and international teams.

What we offer:

• A key role with real ownership of a business-critical platform and visible impact on approval rates, stability and time to market.

• The mandate and support to modernise processing with automation and AI.

• Competitive salary and performance-based rewards.

• Paid vacation, sick leave and public holidays.

• Flexible working hours and modern equipment.

• An international team of payments professionals in a fast-growing fintech.

About Unlimit

Unlimit is the global financial infrastructure for the borderless agentic economy. Designed to bridge the gap between fragmented local markets and the future of autonomous commerce, Unlimit provides the programmable operating layer for the world’s most ambitious businesses.

Through an integrated technology stack, the platform unifies global payment acceptance, programmable financial accounts, and digital asset rails into a singular financial layer. By mapping hyper-local payment ecosystems directly into its architecture, Unlimit enables businesses to move value and settle transactions instantly across continents.

Built on decades of hard-won regulatory depth and an extensive global license portfolio, the platform provides direct access to a massive global infrastructure. With major hubs in London, San Francisco, Singapore, São Paulo, and Mexico City, Unlimit is building the infrastructure that makes global expansion a matter of code, not geography.

About the role:
We are looking for a senior engineer to become the technical lead of our card processing platform. You will own the SmartVista ecosystem end to end (FrontEnd and BackOffice), set the standards for how processing is built, changed and operated, and lead the work of finding and closing gaps in our processes, configuration and controls.

This is not a pure support or configuration role. We expect you to replace manual work with automation and to put AI to practical use in processing operations: anomaly detection, intelligent alerting, automated root-cause analysis and AI-assisted analysis of scheme specifications and transaction data. The role combines card processing expertise + technical leadership + engineering (backend, scripting, integrations) + automation and AI adoption.

What you will do:

1. Technical leadership and platform ownership

• Own the end-to-end architecture of the processing ecosystem (SmartVista FrontEnd and BackOffice, interfaces, HSM, scheme connectivity) and make architecture and technology-stack decisions.

• Act as the technical lead and senior escalation point for processing engineers; set engineering standards, review solutions.

• Lead major incidents, coordinate the response with internal teams, the vendor and card schemes, and drive post-incident reviews to permanent fixes.

• Manage the relationship with the SmartVista vendor on releases, patches, defects and change
  requests.

2. Process ownership and gap remediation

• Map the current processing processes (authorisation, clearing, settlement, disputes, reconciliation, reporting, release and change management, monitoring and on-call) and identify gaps, single points of failure and manual workarounds.

• Build and run a remediation plan: define owners, deadlines and measurable outcomes, and follow through to closure.

• Introduce and maintain operational standards: runbooks, release and change procedures, incident and problem management, SLAs and KPIs (e.g. availability, approval rate, incident resolution time).

• Make sure scheme mandates and regulatory changes are tracked, assessed and implemented on time, and that the evidence of compliance is documented.

3. Processing development and scheme compliance

• Deliver the technical implementation of new card products and services (acquiring and issuing) for Visa, Mastercard, UnionPay, American Express and other schemes.

• Translate scheme mandates and specifications into technical solutions, and lead certification projects with the schemes.

• Configure and develop SmartVista FrontEnd and BackOffice products, services and business rules.

• Prepare technical requirements for system upgrades; test and install releases and patches with minimal downtime.

• Diagnose complex issues across authorisation, clearing and settlement flows and drive them to root cause.

• Set up and maintain payment system emulators and test environments; take part in go-live and pilot activities.

• Maintain clear technical documentation of the platform and implementation procedures.

4. Monitoring and observability: design, development and implementation

• Design and build an end-to-end monitoring framework for the processing platform, covering infrastructure, applications, interfaces and business metrics.

• Develop and implement real-time monitoring of:

• authorisation flows: approval and decline rates by scheme, BIN, issuer country, merchant, MCC and response code.

• response times, timeouts and stand-in processing.

• scheme, issuer and HSM connectivity and host availability.

• transaction volumes and abnormal spikes or drops.

• Develop and implement monitoring of back-office processes:

• clearing file generation, submission and acknowledgement (Visa, Mastercard and other schemes).

• incoming scheme files and reports, settlement positions and reconciliation breaks.

• end-of-day and batch jobs, interchange and fee calculation, chargeback and dispute deadlines.

• Monitor scheme compliance indicators (e.g. decline-code usage, data-integrity edits, excessive retries, fraud and dispute ratios) to catch issues before they become scheme non-compliance or fines.

• Define thresholds, alerting rules and escalation paths; integrate alerts with on-call, incident management and messaging tools.

• Build operational dashboards for engineering, operations and management, and define the related KPIs and SLAs.

• Develop health checks, synthetic test transactions and log-based monitoring for SmartVista components.

• Continuously tune monitoring to reduce false alerts, and turn incident findings into new checks and controls.

5. Automation and AI

• Identify manual and repetitive processes and automate them, including:

• reconciliation and settlement.

• scheme file exchange and report submission.

• testing, regression and release management.

• monitoring and alerting.

• Build CI/CD pipelines and automated deployment for processing components and configuration.

• Design and deliver AI-driven solutions for processing operations, for example:

• anomaly detection on transaction flows, decline patterns and fraud signals.

• intelligent alerting that reduces noise and escalates what matters.

• automated root-cause analysis of declines and incidents

• AI assistants or agents that analyse scheme specifications, mandates and authorisation messages and flag deviations.

• Introduce test automation and regression frameworks for scheme messages and processing flows.

• Promote the safe use of AI tools across the team, with appropriate controls for data security, PCI DSS and human oversight of changes to production.

What you bring:

• 6+ years of hands-on experience in card processing, covering the full transaction lifecycle: authorisation, clearing, settlement, chargebacks and reconciliation.

• At least 2 years in a senior, lead or architect role, with a track record of owning a processing platform and leading engineers, directly or as a technical lead.

• Strong practical experience with SmartVista (FrontEnd and/or BackOffice); deep experience with acomparable platform (e.g. Way4, TranzWare) may be considered.

• Proven experience of improving processes: finding operational gaps, designing controls and delivering a remediation plan to completion.

• Certification experience with Visa and Mastercard and the ability to read and apply scheme specifications and rules (ISO 8583, Visa Base I/II, Mastercard IPM/CIS).

• Hands-on automation skills: Python, SQL/PL/SQL, Bash; experience with CI/CD tools (e.g. GitLab CI, Jenkins), test automation and API testing (e.g. Postman).

• Practical experience applying AI or ML in production work, such as anomaly detection, LLM-based tools or agents, or AI-assisted analysis and coding, and a clear view of their limits and risks.

• Working knowledge of Oracle DB, WebLogic, Linux, REST/SOAP web services and HTTP.

• Experience with scheme tools: Visa Edit Package, VCX, Mastercard File Express (MFE) and scheme test tools and emulators (e.g. Mastercard MAX, Visa test systems).

• Good understanding of e-commerce and digital payments: EMV 3-D Secure, tokenisation (VTS/MDES), Apple Pay / Google Pay, recurring payments, AVS.

• Knowledge of card technologies and security: EMV, contactless, HSM (Thales), key management, PCI DSS.

• Experience with release and change management in a 24/7 production environment.

• Fluent English (B2+) for daily communication with card schemes, vendors and international teams.

What we offer:

• A key role with real ownership of a business-critical platform and visible impact on approval rates, stability and time to market.

• The mandate and support to modernise processing with automation and AI.

• Competitive salary and performance-based rewards.

• Paid vacation, sick leave and public holidays.

• Flexible working hours and modern equipment.

• An international team of payments professionals in a fast-growing fintech.