Open to opportunities

Clarence Koh

@clarencekoh

I’m a production support engineer specializing in mission-critical payment systems, incident management, and operational stability.

Singapore

Message

What I'm looking for

I’m looking for a production support role in high-volume, mission-critical payments where I can lead incident/problem resolution, improve resiliency through monitoring and automation, and collaborate cross-functionally to deliver measurable operational stability.

I’m a production support engineer with 5+ years supporting mission-critical payment applications in 24/7 environments. I focus on incident management, application support, and production stability for high-volume financial systems, keeping SLA/SLO compliance at the center of my work.

I’ve supported instant payments and payment gateways end-to-end—investigating and resolving high-priority incidents, coordinating change and release activities, and acting as a liaison between global stakeholders, developers, and infrastructure teams. I use SQL and monitoring tools like Splunk, Geneos, Grafana, ELK, and Zabbix to drive fast, data-backed troubleshooting.

In a key investigation, I analyzed system logic and source code to uncover an undocumented defect impacting revenue calculations (estimated ~SGD700K), then independently developed complex SQL to extract financial data for merchant billing while remediation was expedited. I also created internal FAQs and knowledge articles that reduced L1 and customer ticket escalations by ~30%.

I care about resiliency and operational excellence: I’ve led application deployments and patching, performed JBoss EAP upgrades, supported RHEL and MySQL migrations, and managed change with ITIL-aligned processes to prevent post-patching anomalies. I’m motivated to keep improving monitoring efficiency, reduce recurring issues, and strengthen large-scale payment platform reliability.

Experience

Work history, roles, and key accomplishments

Current

Associate (L2 Support)

Current

Deutsche Bank AG

Jul 2025 - Present (9 months)

Provide L2 production support for critical instant payment applications in a 24/7 environment, ensuring stability and SLA/SLO compliance. Investigate high-priority real-time payment incidents using SQL and monitoring tools and coordinate incident/release activities across global stakeholders.

SQL Linux Splunk Grafana ITIL Aligned Support Patching

eNETS Lead Engineer (L2)

Network for Electronic Transfers (eNETS)

Sep 2023 - Jul 2025 (1 year 10 months)

Delivered 24/7 L2 support for eNETS payment gateway payment flows (Credit/Debit incl. 3DS & non-3DS, Direct Debit, QR), resolving merchant incidents via ServiceNow. Led investigations and operational improvements, including uncovering an undocumented revenue defect (~SGD 700K), developing interim SQL extraction for ~4 months, and reducing L1/customer ticket escalations by ~30%.

Payment Gateways SQL ServiceNow Zabbix JBoss EAP Upgrades RHEL

IWPS/WPOL Deputy Team Lead

NCS

Sep 2022 - Sep 2023 (1 year)

Managed workload allocation and team activities for IWPS/WPOL support, ensuring SLA compliance across incidents. Coordinated timelines for bug fixes and enhancements and represented the team in stakeholder meetings when required.

Team Leadership SLA Incident Management Bug Fix Coordination Stakeholder Management Change Release Support

Production Support Consultant (L2/L3)

NCS

Nov 2019 - Sep 2022 (2 years 10 months)

Investigated and resolved batch job failures and server outages while supporting 24/7 production maintenance activities. Performed SQL/PLSQL data patching, managed configuration changes and deployments, and created UAT test cases to replicate production issues, reducing recurring incidents and improving system stability.

SQL Pl SQL Batch Processing Production Support UAT Test Case Design Deployment Server Outage Triage Java & Middleware Upgrades

Project Development Software Engineer

NCS

Aug 2019 - Nov 2019 (3 months)

Used SonarQube to detect and fix code issues for the MSW project. Supported application deployments by executing Docker container deployment commands and preparing Linux environments using MobaXterm.

SonarQube Docker Linux Deployment MobaXterm Defect Fixing