Senior GIS Engineer / Tech Lead

Role Overview
The Senior GIS Engineer / Tech Lead is the technical authority for a production Esri ArcGIS Enterprise environment supporting a Singapore government statutory board. This role leads complex service request delivery through the full software development lifecycle, owns platform administration for ArcGIS Enterprise and the underlying Microsoft SQL Server geodatabase, and leads incident resolution for critical production issues.

Embedded within this role is a DevSecOps remit - OWASP Top 10 reviews, secure coding practices, AES-256 encrypted data transfers, penetration test remediation, and code reviews. The Tech Lead also acts as the technical mentor for the GIS Support Engineer, drives architectural decisions, and maintains the technical design documentation for the platform.

Key Responsibilities

Service Request Delivery (Full Software Development Lifecycle)
. Lead the design, development, unit testing, UAT support, deployment, and documentation of complex service requests on the ArcGIS Enterprise platform.
. Prepare technical feasibility analyses, design specifications, and impact assessments for proposed changes.
. Perform change impact analysis, rollback planning, and deployment co-ordination with the client's infrastructure FM team.

ArcGIS Enterprise Platform Administration
. Administer the ArcGIS Enterprise Standard stack - Portal for ArcGIS, ArcGIS Server, ArcGIS Data Store, and Web Adaptor - including health monitoring, configuration, and version upgrades.
. Manage ArcGIS Pro (Creator and Professional) licences, user entitlements, and named-user provisioning.
. Maintain map services, REST API endpoints, layer publication, tile caches, and geoprocessing services.
. Own geodatabase management - schema design, spatial indexing, geodatabase compression and analysis, and performance tuning of SQL Server spatial workloads.
. Optimise map, data, and service performance so that map and data loading meets or exceeds the 60-second threshold in at least 90% of cases.

Incident Management (Sev-1 / Sev-2 Lead)
. Act as the technical incident commander for Severity 1 critical incidents drive rapid bypass, full resolution, and permanent fix within contracted timelines.
. Lead Severity 2 investigation and resolution co-ordinate with the client's FM team for any infrastructure-related issues.
. Author preliminary and full post-incident review reports, including cause analysis, corrective actions, and preventive measures.
. Track and update incident progress on the client's helpdesk support platform and associated trackers.

DevSecOps & Secure Engineering
. Integrate security into the SDLC - threat modelling for new features, OWASP Top 10 checks on all code, static analysis, and secure code reviews.
. Implement and maintain AES-256 encryption for classified data transfers over SFTP (including key management).
. Support independent penetration tests and vulnerability assessments lead remediation of findings.
. Ensure the system is free from known vulnerabilities (injection, XSS, CSRF, broken authentication, insecure storage, insufficient transport layer protection, unvalidated redirects, and similar).
. Participate in and support security and compliance audits provide technical evidence and remediation within agreed timelines.

Batch Jobs, REST APIs & Integrations
. Maintain scheduled batch jobs - monitoring, failure diagnosis, and root-cause resolution.
. Maintain REST API endpoints serving downstream systems manage versioning, backward compatibility, and documentation.
. Co-ordinate with the client's infrastructure FM team, Esri support, and third-party vendors for integrated issue resolution.

Patch Management & Upgrades
. Assess ArcGIS Enterprise point releases, patches, and version upgrades plan and execute upgrades with minimum disruption.
. Assess operating system (Windows Server 2019), database (SQL Server 2019), and browser/client software patches for compatibility and impact.
. Plan and co-ordinate scheduled solution downtime in line with the client's change management procedure.

UAT Environment & Test Support
. Maintain the ArcGIS Enterprise application layer on the UAT environment refresh base test data sets and support end-to-end flow testing at no additional cost.
. Prepare and review UAT plans ensure UAT acceptance criteria are met before production deployment.

Technical Leadership & Mentorship
. Serve as technical authority for all design and architecture decisions on the platform.
. Mentor the GIS Support Engineer conduct peer code reviews and quality assurance on their deliverables.
. Monitor Esri release notes, industry trends, and platform updates brief the client on new features and relevant roadmap items.
. Maintain and continuously improve the platform's technical documentation - functional specs, design specs, architecture diagrams, user guides, administration guides, and software inventories.

Key Requirements

Experience (Mandatory)
. Minimum 5 years of hands-on GIS application development and maintenance experience.
. At least 2 years of demonstrated experience working with Esri ArcGIS software (ArcGIS Enterprise and/or ArcGIS Pro).
. Experience leading Severity 1 incident resolution in a production environment with formal SLAs.
. Experience owning at least one end-to-end ArcGIS Enterprise deployment, upgrade, or major platform change.

Core Technical Skills
. Esri ArcGIS Enterprise Standard (v11.3 or above) - Portal, Server, Data Store, Web Adaptor administration, map services, tile caches, and REST endpoints.
. Esri ArcGIS Pro - geoprocessing, map authoring, and geodatabase management.
. Microsoft SQL Server (2019 or above) - enterprise geodatabase, spatial indexing, query tuning, and maintenance.
. Windows Server 2019 operations - services, tasks, logs, and scripted administration.
. Core programming technologies: .NET (C#/ASP.NET), Python (ArcPy, scripting automation), JavaScript (incl. ArcGIS API for JavaScript), HTML, and T-SQL.
. Secure file transfer using SFTP with AES-256 file-level encryption key management and secure data handling.
. Source control (e.g. Git), issue/change tracking, and helpdesk platforms for progress tracking.

Security & Governance
. Solid working knowledge of the OWASP Top 10 and secure coding practices for web applications.
. Experience supporting independent security audits, penetration tests, and remediation planning.
. Awareness of Singapore government ICT security policies, data classification handling, and change management disciplines.

Qualifications
. Bachelor's degree in Computer Science, Geographic Information Systems, Geomatics, Information Technology, Engineering, or a related discipline.
. Must be Singapore-based and eligible to work in Singapore.
. Able to obtain and maintain the relevant government security clearance for the engagement.

Personal Attributes
. Strong analytical and problem-solving skills calm under pressure during critical incidents.
. Self-motivated stays current with Esri releases, SQL Server updates, and related technology trends.
. Clear written and verbal English communication comfortable writing technical documentation and incident reports.

Nice-to-Have Qualifications
. Esri certifications - ArcGIS Enterprise Administration Associate/Professional, ArcGIS Pro Professional, or ArcGIS Developer Professional.
. Microsoft SQL Server certifications (Azure Database Administrator Associate or equivalent).
. Certified Information Systems Security Professional (CISSP), CSSLP, or equivalent security certification.
. Experience with Government Commercial Cloud (GCC 2.0) or hardened intranet-zone deployments.
. Experience with ArcGIS Online, FME, or ETL tooling for spatial data.
. Familiarity with containerised or CI/CD-based deployment patterns.
. Prior DPTM (Data Protection Trustmark) or PDPA implementation experience.
. Experience supporting 24x7 on-call coverage for geospatial platforms.