Senior PostgresSQL Developer

Senior PostgreSQL Developer
Client: IRS
Clearance: MBI required (Moderate Risk Background Investigation) Experience: 5+ years of relevant industry experience
Work Location: Remote
Position Overview
Zenius is seeking an experienced Senior PostgreSQL Developer to support an IRS program through our partner. The ideal candidate will have strong hands-on experience developing, optimizing, and troubleshooting PostgreSQL databases, with particular depth in SQL/query performance, indexing, PL/pgSQL development, database tuning, and production troubleshooting. The candidate should be able to analyze real-world database performance issues end-to-end, identify the underlying cause, evaluate alternatives, implement an appropriate solution, and validate the resulting performance improvement.
Key Responsibilities
Develop, optimize, and maintain complex PostgreSQL queries, stored procedures, functions, and database objects.
Diagnose slow-running queries using EXPLAIN/EXPLAIN ANALYZE, query execution plans, planner statistics, and cost estimates.
Rewrite and optimize SQL queries to improve application and database performance.
Design and optimize PostgreSQL indexes, including B-tree, GIN, GiST, and BRIN indexes, as well as partial and covering indexes.
Evaluate indexing strategies based on query patterns and read-versus-write performance tradeoffs.
Develop and optimize stored procedures and functions using PL/pgSQL.
Troubleshoot database concurrency issues involving transaction isolation, locking, blocking, and deadlocks.
Monitor and optimize database health using pg_stat_statements, pg_stat_activity, and related PostgreSQL diagnostic capabilities.
Manage and tune VACUUM, ANALYZE, and autovacuum processes to address table/index bloat and maintain database performance.
Tune PostgreSQL configuration parameters such as shared_buffers, work_mem, effective_cache_size, and other performance-related settings.
Design and maintain database partitioning strategies using PostgreSQL declarative partitioning.
Support streaming and logical replication configurations and troubleshoot replication-related issues.
Support PostgreSQL backup and recovery processes using pg_dump, pg_basebackup, WAL archiving, and Point-in-Time Recovery (PITR).
Design and review database schemas, including normalization/denormalization decisions, constraints, appropriate data types, and JSONB usage.
Collaborate with application developers, architects, DevOps engineers, and other technical teams to resolve database-related performance and reliability issues.
Document database designs, performance improvements, troubleshooting procedures, and technical recommendations.
Required Qualifications
Minimum 5 years of industry experience in database development, database engineering, or a closely related technical role.
Strong hands-on experience with PostgreSQL development and performance optimization.
Advanced SQL skills with demonstrated experience troubleshooting and optimizing complex queries.
Strong understanding of PostgreSQL query planning and the ability to interpret EXPLAIN ANALYZE output.
Hands-on experience designing and tuning PostgreSQL indexes.
Strong Experience Developing PL/pgSQL Stored Procedures And Functions.
Understanding of PostgreSQL transaction management, isolation levels, locking, and deadlock troubleshooting.
Experience with PostgreSQL database configuration and performance tuning.
Experience with VACUUM, ANALYZE, autovacuum, and database bloat management.
Experience using PostgreSQL monitoring and diagnostic capabilities, particularly pg_stat_statements and pg_stat_activity.
Working knowledge of PostgreSQL partitioning, replication, backup, and recovery.
Strong understanding of relational database and schema design principles.
Strong analytical and troubleshooting skills.
Ability to obtain and/or maintain the required MBI clearance/background investigation for the IRS engagement.
Bachelor's degree in Computer Science or equivalent.
Preferred Qualifications
Previous experience supporting IRS, Treasury, or other U.S. federal government systems.
Experience supporting large-scale, high-volume, or mission-critical PostgreSQL environments.
Experience migrating or modernizing applications/databases to PostgreSQL.
Experience working in cloud or containerized environments.
Familiarity with database automation, CI/CD, DevSecOps, and infrastructure automation practices.
About The Company
Headquartered in Leesburg, Virginia, Zenius Corporation is a HUBZone-certified small business. Zenius specializes in providing Grants Management, IT Modernization, Acquisition Management, and Financial Management services to Federal agencies. Zenius is selected by Inc 5000 as one of the fastest-growing companies in the DC Metro Area, awarded in 2025, 2024, 2021, and 2020. Zenius is also listed by Financial Times as one of the fastest-growing companies in the Americas in 2021. Zenius is an awardee of the 2019 Best of Leesburg winner (Business Management Consultant category).
Benefits
Zenius Corporation is an employee-oriented company. Join us now and help us grow!
We offer a competitive benefits package that includes paid holidays and paid time off, medical insurance (health, vision, and dental), 401K matching, a Flexible Spending Account, and flexible schedules, as needed. We also support employees with training and professional certification plans that benefit them.
Equal Opportunity Employer
Zenius Corporation provides equal employment opportunities (EEO) to all employees and applicants for employment without regard to race, color, religion, gender, sexual orientation, gender identity or expression, national origin, age, disability, genetic information, marital status, amnesty, or status as a covered veteran in accordance with applicable federal, state, and local laws. Zenius complies with applicable state and local laws governing non-discrimination in employment in every location in which the company has facilities. This policy applies to all terms and conditions of employment, including, but not limited to, hiring, placement, promotion, termination, layoff, recall, transfer, leaves of absence, compensation, and training.
Zenius Corporation expressly prohibits any form of unlawful employee harassment based on race, color, religion, gender, sexual orientation, gender identity or expression, national origin, age, genetic information, disability, or veteran status.

Work arrangement
Yes