Senior Database Administrator (Freelancer)

Mactores is the agent-native AWS modernization firm. Most modernization work doesn't ship, it stalls in pilots, slips a year, or lands at three times the budget. We exist to ship it: production systems running, legacy retired, outcomes measured. Our delivery is built on Aedeon, the agent platform built by Mactores' founders' sister company, which absorbs the repetitive 60–70% of engagement work, discovery, dependency mapping, validation, test generation, that traditional consulting bills human hours against. Forward-deployed engineers own the rest: architecture, judgment, and cutover, on dates we commit to in the contract.

Oracle-to-PostgreSQL migrations don't fail at conversion. They fail at go-live DMS latency nobody diagnosed, autovacuum behavior nobody tuned, privilege mappings nobody tested, incidents nobody owns at 2 a.m. This role sits inside our Application & Database Modernization pillar and exists to make sure that doesn't happen.

As our Senior Database Administrator, you'll run the Amazon Aurora PostgreSQL environments in an active Oracle-to-PostgreSQL migration program from cluster design through DMS replication through post–go-live stabilization. Aedeon handles the repeatable conversion and validation work; you own what agents can't: production judgment. When replication lags, when a workload misbehaves after cutover, when an incident escalates past L2, you're the person who resolves it and can explain why it happened.

This is a freelance engagement, remote, working as the L3 escalation point on production systems that real businesses run on.

What you will do?

• Design, set up, configure, and manage Amazon Aurora PostgreSQL clusters.
• Configure parameters, maintenance windows, monitoring, and scaling strategies.
• Keep the environments highly available, fault tolerant, and operationally ready — before go-live, not after.
• Map users, roles, and privileges from Oracle to PostgreSQL.
• Implement least-privilege access, role hierarchies, and security best practices, and support audit and compliance requirements.
• Configure, run, monitor, and optimize AWS DMS tasks (Full Load and CDC).
• Troubleshoot DMS latency, data mismatches, and performance issues, and tune DMS settings for large-volume, high-throughput workloads.
• Tune server and database performance — CPU, memory, I/O, connections — plus PostgreSQL parameters, autovacuum, indexing, and query behavior.
• Find performance bottlenecks before the customer does, and resolve them.
• Design and implement backup and restore strategies; define and test DR and failover procedures; support cross-region replication and recovery drills.
• Lead post–go-live stabilization: monitor production workloads, resolve incidents, and act as the L3 escalation point for database-related production issues.
• Deliver operational documentation and handover support, so what you stabilized stays stable after you.

What are we looking for?

• 5+ years of experience administering Amazon Aurora PostgreSQL.
• Proven expertise supporting Oracle-to-PostgreSQL migrations.
• Hands-on experience with AWS DMS.
• Advanced PostgreSQL performance tuning and troubleshooting skills.
• Strong knowledge of backup, restore, and DR planning in AWS.
• Experience with AWS monitoring tools (CloudWatch, Performance Insights).
• Strong problem-solving and root-cause analysis abilities.
• Experience working in production and post–go-live environments.
• The ability to work independently as an L3 escalation engineer.
• Clear communication and documentation skills.

You will be preferred if

• Familiarity with automation and configuration management tools, such as Ansible, Chef, or Puppet
• Familiarity with IAAC tools such as Terraform, CloudFormation
• Familiarity with CI/CD implementation tools like Liquibase/Flyway
• AWS Certified Database – Specialty
• AWS Certified Solutions Architect

How we work?

We refactor legacy databases to cloud-native AWS on a committed date, with Mactores carrying delivery overage risk for delays we cause. Aedeon absorbs the repetitive majority schema conversion, test generation, regression harnesses. Engineers absorb the judgment: risk tradeoffs, production cutover, post-cutover optimization. You're the judgment layer for this program's production environments. When we tell a customer their database will be stable on a date, your work is what makes that sentence true.