Wissen Technology - Associate Database Developer - PostgreSQL

Job Description :

Key Responsibilities :

• Design, develop, maintain, and optimize PostgreSQL databases in production environments.
• Write and optimize complex SQL queries involving joins, aggregations, CTEs, window functions, upserts, and DDL.
• Analyze execution plans and systematically troubleshoot slow SQL queries.
• Manage database transactions, isolation levels, locking, and Multi-Version Concurrency Control (MVCC).
• Design and maintain database tables, keys, constraints, indexes, and partitioning strategies.
• Plan and execute data migrations, including bulk and incremental loads, cutovers, and data validation.
• Manage database backup and restore processes, including retention policies, point-in-time recovery, and restore testing.
• Develop reliable operational scripts and idempotent reconciliation and backfill processes.
• Use Python for data loading, automation, and operational scripting.
• Monitor database performance and identify opportunities to improve reliability, scalability, and efficiency.

Required Skills & Experience :

• 5 years of hands-on PostgreSQL experience in production or production-adjacent environments.
• Strong SQL skills, including joins, aggregation, common table expressions (CTEs), window functions, upserts, and DDL.
• Experience analyzing execution plans and optimizing slow SQL statements.
• Practical understanding of transactions, isolation levels, locking, and MVCC.
• Experience with physical database design, including tables, keys, constraints, indexes, and partitioning.
• Hands-on experience with data migrations, bulk and incremental loads, cutovers, and data validation.
• Practical knowledge of database backup and recovery, retention policies, point-in-time recovery, and restore testing.
• Ability to write reliable operational scripts and idempotent reconciliation or backfill processes.
• Basic Python experience for data loading and operational automation.

Nice to Have :

• Experience with schema migration tools such as Alembic, Flyway, or Liquibase.
• Experience managing declarative partitioning at scale.
• Experience with managed cloud PostgreSQL services.
• Experience tuning PostgreSQL statistics, autovacuum, database bloat, and lock contention.