Constantin Mihai Stefan

• Main achievement: Eradicated fragmented and high-maintenance user-role mechanisms by architecting a new cloud-agnostic IAM microservice. By migrating legacy policies to a role-and-task tertiary application using both SOAP and REST APIs, I achieved a clean separation of responsibilities for user provisioning, effectively future-proofing the system for multi-cloud evolution and reducing architectural technical debt. • Eliminated architectural fragmentation by designing a reusable domain service layer across 7 bounded contexts - decoupling business logic from data access through repository patterns and aggregate roots, significantly improving maintainability and enabling independent scalability per domain. • Transformed internal development efficiency by automating 90% of repetitive operational workflow; by orchestrating standardized scheduled scripts, I successfully streamlined engineering teams workflows thus harboring focus for higher-value features. • Established a quality first culture by integration of mandatory pull request analysis, reducing bug introduction by 80% and minimizing manual reviews. • Orchestrated a 30-day pilot program to evaluate AI-assisted development tools, bridging the gap between emerging tech and practical engineering. By designing standardized prompt engineering frameworks and reporting on technical trade-offs, I accelerated department-wide AI adoption and established the foundational best practices for secure, high-speed AI integration.

• Main achievement: Reduced ongoing maintenance effort by 50% through targeted application modernization and root-cause analysis and problem management. • Successfully migrated legacy applications built on ColdFusion to Node.js resulting in an increase of 15% of application performance. • Boosted system performance by optimizing a core functionality with over 20 econometric dimensions, reducing average latency from 900ms to 20ms and allowing a 4x increase in user load. • Rearchitected data layer by transitioning from a horizontal model to a vertical one, which resulted in minimization of storage used by 30%. • Architected and implemented historical data and visualization capabilities which led to improved decision making by stakeholders.

• Main achievement: Led enterprise-scale cloud transformation across 30+ legacy retail systems - reducing infrastructure spend by 20% while increasing application availability from 90% to 99.5%, establishing a resilient foundation for ongoing digital modernization. • Identified and permanently resolved critical bottlenecks across retail procurement and merchandising workflows — eliminating an average of 20 weekly support requests and restoring operational continuity across store-facing systems. • Stabilized Oracle production environments for 2,000+ retail and supply chain users by implementing a high-performance database governance framework. By executing real-time SQL tuning, resolving systemic locking issues and delivering standardized runbooks for support teams, I reduced P1 incidents by 70%, improved response times by 75%, and slashed MTTR from 90 to 30 minutes.

• Main achievement: Protected retail business continuity by architecting early detection of data inconsistencies across 3 core enterprise systems spanning store operations and head office, significantly reducing downstream impact of data loss between retail stores and head office by 50%. • Architected 5 major features across core retail operations - spanning merchandising, promotions and supply chain workflows by creating backward-compatible APIs resulting in secure and error free production deployment. • Prevented performance degradation by auditing critical supply chain and fulfilment architectures across the retail transaction lifecycle, fully documenting integration points and dependencies and proactively eliminating 4+ critical bottlenecks.

• Main achievement: Orchestrated over an 8-month period a turnaround of a low-performing monitoring team characterized by having low ownership and high escalation rates. By maturing incident handling protocols and implementing a context-first problem analysis, I succeeded in transforming the team into the department’s top-performing one, establishing a standard for operational handovers. • Neutralized cross-departmental friction by automating 5 critical internal workflows, allowing teams to focus on purpose rather than gatekeeping, thus improving organizational mentality