Senior GIS Database Migration Architect

Role: Senior GIS Database Migration Architect

Location: Houston, TX (hybrid)

Duration: 6 month Contract-to-Hire

Apex Systems is seeking a senior, hands-on GIS database migration architect to serve as the primary technical lead for an enterprise Oracle-to-PostgreSQL/PostGIS GIS migration assessment. This person will perform the majority of the technical discovery, analysis, architecture, documentation, and roadmap development required to assess a large Esri Enterprise Geodatabase environment and prepare a defensible migration plan. The engagement is assessment-focused: the role will validate current-state conditions, identify compatibility and dependency risks, define remediation options, and build the phased migration roadmap/runbook. Production migration execution is not part of this phase.

Core Responsibilities

1. Lead Current-State Technical Assessment

• Plan and execute technical discovery for the in-scope Lower 48 Esri Enterprise Geodatabase environment, including the Oracle database, ArcGIS Enterprise/Portal services, ETLs, source systems, and downstream consumers.
• Create and maintain an inventory of candidate databases, schemas, tables, feature classes, layers, services, schedules, interfaces, and ownership information provided during the assessment.
• Analyze Esri geodatabase constructs and relational dependencies, including spatial data types, domains, subtypes, relationship classes, attachments, Global IDs, attribute rules, versioning, and other behavior that must be preserved or redesigned.
• Validate available environment documentation through stakeholder interviews, metadata review, SQL analysis, service inspection, and limited exploratory testing in the existing PostgreSQL/PostGIS development environment.

2. Perform Oracle-to-PostgreSQL/PostGIS Compatibility Analysis

• Assess Oracle-to-PostgreSQL/PostGIS conversion risks across schemas, data types, date and time handling, sequences and identifiers, spatial references, geometry behavior, indexing, constraints, privileges, and performance considerations.
• Evaluate Esri library and platform-functionality gaps between the current Oracle/Esri implementation and the proposed PostgreSQL/PostGIS target.
• Determine how attachments, related records, Global IDs, relational integrity, and service dependencies can be preserved and validated.
• Identify technical gaps, migration blockers, assumptions, decisions, and remediation options. Clearly distinguish confirmed findings from items requiring client validation.
• Assess the feasibility and implications of parallel operations, dual-write ETL patterns, reconciliation, rollback, and phased cutover approaches without executing a production migration.

3. Map Integrations, ETLs, and Operational Dependencies

• Document known ETLs, source systems, schedules, transformation logic, and consuming services for candidate layers.
• Identify and flag dependencies and reconnection risks involving ArcGIS Portal, Survey123, FME, Spotfire, Power BI, APIs, scheduled jobs, and other real-time or batch consumers.
• Work with the GIS Operations Lead to understand operational workflows, service criticality, support patterns, outage tolerance, and sequencing constraints.
• Define validation and reconciliation approaches for data completeness, schema conformance, spatial accuracy, service behavior, and downstream connectivity.

4. Develop Governance and Target-State Recommendations

• Contribute database-layer recommendations for ETL governance, naming, metadata, lineage, spatial reference and datum standards, access, change control, backup, retention, and lifecycle management.
• Support definition of future-state data-domain ownership and an operating model that reduces recurrence of unmanaged data and service sprawl.
• Translate assessment evidence into practical architecture decisions, standards, decision logs, risks, and remediation priorities.
• Ensure recommendations fit the supported Esri, PostgreSQL/PostGIS, security, networking, monitoring, resilience, and operational requirements identified during the engagement.

5. Build the Migration Roadmap and Runbook

• Own the technical content for a phased migration roadmap/runbook covering wave planning, sequencing, prerequisites, resource needs, validation gates, cutover considerations, rollback planning, risk mitigation, and operational transition.
• Develop estimates and planning assumptions for a subsequent migration phase based on assessed complexity, dependencies, remediation requirements, and client decisions.
• Produce clear diagrams, inventories, findings, decision matrices, risk registers, and executive-ready recommendations that support the three primary assessment deliverables.
• Present findings to technical and business stakeholders and incorporate review feedback while maintaining alignment to the agreed assessment scope.

6. Support Future Azure Readiness Without Expanding Scope

• Evaluate whether on-premises PostgreSQL/PostGIS recommendations create avoidable rework for a potential later move to Azure Database for PostgreSQL or another approved Azure-hosted pattern.
• Partner with the Cloud Architecture Reviewer on targeted questions involving identity, connectivity, security, monitoring, backup, resilience, integration dependencies, and Esri supportability.
• Document cloud-related considerations and decision points as future-state guidance. Do not design or execute the subsequent cloud migration during this assessment.

Required Qualifications

• 8+ years of progressively responsible GIS, spatial database, database architecture, or data migration experience, including substantial hands-on work in enterprise Esri environments.
• Demonstrated experience assessing or planning migrations from Oracle Enterprise Geodatabases to PostgreSQL/PostGIS. Direct migration implementation experience is strongly preferred.
• Advanced Oracle skills, including SQL, schema and dependency analysis, data types, spatial capabilities, indexing, query analysis, security, and migration risk identification.
• Advanced PostgreSQL/PostGIS skills, including spatial types and functions, schema design, indexing, query tuning, permissions, backup and recovery considerations, and operational support patterns.
• Strong working knowledge of ArcGIS Enterprise 11.x, Portal for ArcGIS, ArcGIS Server, Enterprise Geodatabases, ArcGIS Pro, services, attachments, Global IDs, relationship classes, versioning, and spatial references.
• Experience analyzing ETL and integration patterns using tools such as FME, Python, SQL, ArcPy, APIs, scheduled jobs, or comparable orchestration approaches.
• Working knowledge of Azure architecture relevant to PostgreSQL/PostGIS and Esri workloads, including identity, networking, private connectivity, monitoring, backup, resilience, security, and migration planning.
• Ability to independently lead technical discovery, facilitate workshops, document complex environments, evaluate trade-offs, and convert findings into client-ready reports and roadmaps.
• Excellent written and verbal communication, with the ability to explain database and GIS risks to architects, operations leaders, project stakeholders, and executives.

Preferred Qualifications

• Experience in oil and gas, utilities, infrastructure, or another asset-intensive environment with large enterprise GIS estates.
• Experience with ArcGIS Online, Survey123, Power BI, Spotfire, Snowflake-hosted PostgreSQL patterns, and hybrid on-premises/cloud architectures.
• Experience designing data validation, reconciliation, profiling, lineage, metadata, and governance controls for spatial data migrations.
• Familiarity with Azure Database for PostgreSQL, Azure networking and identity patterns, infrastructure-as-code, CI/CD, and observability practices.
• Relevant Esri, PostgreSQL, Oracle, Microsoft Azure, or data architecture certifications. Certifications are valued, but demonstrated delivery experience is more important.