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 Mac