October 2025 monthly summary for backend-developers-ltd/ComputeHorde. Key features delivered: Implemented receipt validation duplicate filtering by tracking seen job_uuid in filter_valid_excuse_receipts; added comprehensive unit tests for the validator module. Major bugs fixed: Duplicates in receipt validation no longer affect results, improving accuracy and reliability. Overall impact: enhanced data integrity in validation workflow, reduced risk of incorrect approvals, and stronger test coverage enabling safer future changes. Technologies/skills demonstrated: backend Python development, robust validation logic, unit testing (test-driven approach), version control discipline, and focused bug-fix engineering. Business value: more reliable billing/expense processing, reduced manual verification, and improved customer trust.