Valentin-Flavian Draganescu

Summary: Led the end-to-end architecture and delivery of UPCARS, a production-grade Recommender System built from the ground up. Aligned AI researchers, data scientists, backend/frontend engineers, and marketing to ship personalized recommendations with measurable impact on engagement and conversion.

Leadership & Responsibilities

• Owned product & technology strategy for personalization; translated business goals into a roadmap, budgets, and measurable KPIs (CTR, CVR, ARPU, retention).
• Directed a cross-functional team (AI/ML, data engineering, backend, QA, DevOps, marketing) through discovery → design (RFCs/tech specs) → build → test → launch.
• Drove project management: scope, risk, and dependency management; stakeholder updates; release planning; vendor selection; compliance/security reviews.
• Established engineering standards: coding guidelines, model/feature governance, Definition of Done, incident management, and on-call procedures.

Architecture & System Design (UPCARS)

• Data platform: designed event schemas (impressions, clicks, dwell time, conversions), ingestion, and ETL/ELT to a data lake;
• Modeling approach: implemented a two-stage pipeline—candidate generation and ranking —with cold-start strategies (content-based, popularity, fallback).
• Serving layer: low-latency online inference with caching and vector search; REST APIs with idempotency, pagination, and AB test headers.
• Experimentation: online A/B testing framework, holdouts, guardrail metrics, and offline metrics (Precision, Recall, Serendipity) to validate model changes.
• Observability: e2e dashboards (data freshness, feature drift, p95/p99 latency, error rates), tracing, and alerting; post-incident reviews to produce runbooks and reduce MTTR.
• Governance & privacy: PII minimization, access, consent handling, data retention, and model-risk reviews; explainability for stakeholder transparency.

Summary: Independent consultant specialising in system architecture on AWS, hands-on Node.js + React delivery, and computer-vision (AI/vision) model integration. Partnered with product and engineering leaders to consolidate teams and practices, improve reliability/performance, and ship measurable outcomes.

Engagements & Responsibilities

• Acted as fractional architect/tech lead/CTO and contributor across discovery → design (RFCs/tech specs) → implementation → testing → CI/CD → production operations.
• Designed cloud architectures for Recommendation Systems, AgriTech, Hospitality platforms and adjacent products: multi-tenant patterns, service boundaries, data models, auth/permissions, and SLAs.
• Built RESTAPIs in Nodejs (TypeScript), background workers/queues, and React front ends (SPA) aligned to accessibility and performance goals.
• Integrated AI/computer-vision models: selected/packaged models, exposed inference via REST/gRPC, implemented preprocessing/post-processing, and added observability for accuracy/recall/serendipity/latency.
• Drove team consolidation: unified coding standards, branching/release strategy, Definition of Done, and incident/runbook practices; mentored engineers and onboarded new hires.
• Implemented security by default (least-privilege IAM, VPC isolation, KMS, audit logging) and cost optimization (right-sizing, storage lifecycle policies, serverless where appropriate).

Architecture & Technologies

• AWS: EC2, Lambda, API Gateway, DynamoDB, RDS/PostgreSQL, S3, CloudFront, SQS/SNS, Step Functions, Elasticsearch/OpenSearch, Load Balancers, CloudWatch (logs/metrics/alarms), CloudTrail, KMS, Cognito.
• Backend: Node.js (TypeScript), Express, REST, JSON/Webhooks, background workers, caching, pagination.
• Frontend: React, Next.js, state/query management, form and data-grid heavy UIs.
• AI/Vision Integration: model serving (SageMaker/EC2/Lambda + containers)
• DevOps & Quality: IaC (Serverless Framework), CI/CD, blue/green & canary deploys

Summary: Progressed from mobile to full-stack and backend leadership. Led a cross-functional team (Backend, DBA, DevOps, QA) to architect, build, test, and operate scalable API services powering Digital Asset Management (DAM) and Project Management applications. Owned service reliability, performance, and cost efficiency on AWS.

Leadership & Responsibilities

• Drove end-to-end delivery of backend services: requirements → architecture → implementation → automated testing → CI/CD → production operations.
• Coordinated cross-functional work (Backend, DBAs, DevOps, QA, Frontend) to align on API contracts, data models, SLAs, and release plans.
• Designed service boundaries and data flows for DAM/PM features (asset ingestion, metadata, search, permissions, projects/tasks/timesheets), emphasizing security and auditability.
• Established coding standards, code reviews, and observability practices (metrics, logs, alerts) to improve MTTR and release quality.
• Partnered with frontend (React) to define efficient payloads, pagination, and error schemas that improved UX and reduced round-trips.
• Optimized infrastructure for scale and cost (autoscaling, caching, right-sizing compute, storage lifecycle policies).

Architecture & Technologies

• Languages/Frameworks: Node.js (services, workers), React (full-stack collaboration).
• AWS: EC2, API Gateway, Lambda, DynamoDB, PostgreSQL (managed), S3, SQS, SES, Elasticsearch, Load Balancers, CloudWatch (logs/metrics/alarms).
• Data & Integrations: RESTful APIs, background jobs/queues, object storage for assets, search indexing, metadata and access control models.
• Quality & Ops: Automated testing, CI/CD, blue/green or rolling deploys, monitoring, incident response, runbook

Summary: Cross-functional leader and mobile architect bridging engineering, design, and stakeholders. Own technology choices (native vs. cross-platform), app architecture, and delivery of user-centric features across Android and iOS. Drive modernization, platform-correct UX, performance, and reliability.

Leadership & Responsibilities

• Define mobile architecture and stack (native Android/iOS vs. cross-platform such as React Native) aligned to product goals, timelines, and team strengths.
• Translate requirements into technical designs/RFCs; establish API contracts, data models, and sequence diagrams; run design reviews and code reviews.
• Partner with designers to align with Material Design and Apple Human Interface Guidelines; champion accessibility and platform-native patterns.
• Ensure compatibility across required OS versions and devices (phones/tablets, multiple orientations), with attention to performance, security, and offline behavior.
• Oversee release management for Google Play and App Store; set standards for CI/CD, testing, observability, and incident response.
• Track emerging trends and deprecations; plan upgrades/migrations (e.g., GCM → FCM, framework updates, OS rollovers) to keep apps current.

Architecture & Technologies Used

• Android: Java framework; WebView integrations (HTML/JS/CSS); notifications via FCM (formerly GCM); local storage with SQLite and Realm; device APIs: Wi-Fi, Bluetooth, NFC, and sensors.
• iOS: Swift / Objective-C frameworks; APNs push notifications; WebView features; device sensors; proximity with iBeacon and Eddystone.
• Backend & APIs: REST services with Node.js + MongoDB; microservices with Spring Boot + PostgreSQL + DynamoDB; API versioning, pagination, auth, and rate-limiting.
• Cross-platform: React Native for shared codebases when appropriate

Summary: Built and shipped native mobile features end-to-end across Android and iOS, translating requirements into performant, platform-correct UI and robust app logic while advising on API/architecture decisions.

Impact & Responsibilities

• Delivered features from spec to release across Android and iOS, implementing UI, navigation, data flow, and network layers.
• Aligned designs with Material Design and Apple Human Interface Guidelines, proposing UI/UX adjustments to improve platform fit and reduce friction.
• Ensured reliable behavior across required OS versions using feature flags, graceful fallbacks, and compatibility shims.
• Built responsive/adaptive layouts that scale across phones and tablets, handling orientation changes and varied screen densities.
• Collaborated on REST API design with backend teams; provided endpoint contracts, pagination/error models, and performance considerations to optimize mobile payloads.
• Instrumented apps for stability and performance (e.g., cold-start time, memory, network usage), prioritizing fixes that improved user experience and release quality.
• Participated in code reviews and architecture discussions to maintain clean patterns (e.g., MVVM/Clean Architecture), testability, and long-term maintainability.