Ramazan is available for hire
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Verified Expert in Engineering
Software Development Developer
Istanbul, Turkey
Toptal member since January 20, 2020
Bio
Ramazan is a senior software architect with 19 years of experience as a full-stack developer, tech lead, fractional CTO, founding engineer, and product manager, working with startups to large enterprises. His expertise spans banking, finance, insurance, crypto trading, autonomous-driving HD maps, enterprise IT, multi-tenant SaaS, and AI systems, covering architecture to cloud and DevOps on AWS, Azure, and GCP. Known for his ability to deliver, he is hardworking, dependable, and a team player.
Portfolio
New Age Safety Solutions Ltd
NestJS, Prisma, PostgreSQL, React, Progressive Web Applications (PWAs), Python...
Siemens
Node.js, React, Apache Kafka, MongoDB Atlas, Amazon EKS, AWS Fargate...
Woven by Toyota
Go, Python, React, FastAPI, Django, PostgreSQL, PostGIS, Amazon Aurora...
Experience
- Software Development - 19 years
- Full-stack - 17 years
- Web Development - 15 years
- IT - 13 years
- IT Product Management - 12 years
- Amazon Web Services (AWS) - 10 years
- Mobile App Development - 10 years
- Migration Planning - 6 years
Preferred Environment
Java, Node.js, React, Python, Terraform, Go, Azure, Kubernetes, GitHub Actions, Amazon Web Services (AWS)
The most amazing...
...project I've built is a real-time crypto order book management system: it streams LP market data, auto-hedges trades, and processes 200 trading pairs at 3–4 ms.
Work Experience
Fractional CTO & Founding Engineer
2026 - 2026
New Age Safety Solutions Ltd
- Acted as a fractional CTO and sole engineer, took Veraxon, a multi-tenant permit-to-work SaaS for UK construction and other high-risk site work, from an empty repository to production in under 4 months, owning product, architecture, and go-live.
- Worked directly with the company's owner, an HSE expert but not a software specialist: gathered and analyzed requirements, negotiated scope, and secured step-by-step sign-off, turning safety practice into a product ready for enterprise clients.
- Researched UK permit-to-work regulations and HSE guidance (HSG250) and designed the platform around them: enforced separation of duties across requester, authoriser, issuer, and acceptor, controlled issue, a 10-year audit trail, and GDPR by design.
- Built a nine-state permit lifecycle for hot works, confined spaces, electrical work, work at height, excavation, and lifting, with digital signatures, pre-work briefings, evidence uploads, extensions, PDFs, and QR verification for site inspectors.
- Designed strict multi-tenancy so many client companies share one platform with fully isolated data: organizations, sites, areas, and contractors, three role tiers, feature-gated subscription plans, and an admin console with audited support sessions.
- Built the full stack in a TypeScript monorepo: NestJS and Prisma on PostgreSQL 18, a React 19 PWA for iOS, Android, and desktop that shares validation contracts with the API, and a Python/FastAPI service producing legally defensible permit PDFs.
- Implemented custom JWT authentication with rotating refresh tokens, invitation onboarding, rate limiting, and a WAF; chose Postmark for transactional email after researching inbox placement for Microsoft 365-based enterprise customers.
- Designed a cost-effective AWS architecture in Terraform: private VPC, ECS Fargate on arm64, an internal load balancer behind API Gateway, CloudFront, RDS, WAF, and alarms, deliberately free of brokers, caches, and queues until load demands them.
- Automated delivery with GitHub Actions and OIDC (no long-lived cloud keys), migration gates, rollback detection, and approved production deploys; backed every release with 610 API end-to-end tests on real PostgreSQL and 289 front-end tests.
- Produced 6 narrated product and marketing videos, tracking licensing for every stock clip, music track, and voice-over; built the veraxon.io landing page and the corporate site nassltd.com (Astro, AWS), live in 3 weeks.
Technologies: NestJS, Prisma, PostgreSQL, React, Progressive Web Applications (PWAs), Python, FastAPI, Amazon Web Services (AWS), Terraform, Amazon Elastic Container Service (ECS), Amazon Elastic Container Registry (ECR), AWS Fargate, Amazon API Gateway, Amazon CloudFront, Amazon RDS, AWS WAF, GitHub Actions, OpenID Connect (OIDC), Postmark, Playwright, Multitenancy, SaaS, GDPR, Software Architecture, Requirements Analysis, Product Management, Vite, Tailwind CSS, TanStack Query, React Hook Form, Zod, WeasyPrint, Docker, Amazon S3 (AWS S3), Amazon Route 53, AWS Secrets Manager, Amazon CloudWatch, AWS Lambda, Astro, Jest, Vitest, Testcontainers, FFmpeg, Video Production, Stakeholder Management, Regulatory Compliance, Amazon, Integration, Back-end Architecture
Senior Software Architect (Hands-on), Product Info Cockpit
2026 - 2026
Siemens
- Served as a hands-on senior architect in a team of 10, designed and largely built Siemens' Product Info Cockpit: one place for product managers to search 3.7 million products with their technical and commercial data, media, documents, and product relations.
- Delivered the greenfield MVP on schedule in 3 months across development, QA, and production AWS accounts, turned UAT defects around within the day, and earned approval of a EUR 270,000 follow-on budget on the strength of that delivery.
- Owned the technical shape end to end and did most hands-on work across infrastructure, back end, front end, and quality, while steering two developers and acting as a technical counterpart to the data-platform, database, and identity teams.
- Built the complete AWS landing zone per environment with Terraform: VPC, EKS on Fargate, load balancer with WAF, container registry, S3, and Secrets Manager with in-cluster secret sync, plus private cluster access and MongoDB Atlas integration.
- Secured sign-in with Microsoft Entra ID (OpenID Connect) at the load balancer, so no request reaches the app unauthenticated; added role- and business-unit-based authorization with an access-request and approval workflow via Microsoft Graph.
- Enforced zero static credentials: GitLab OIDC to AWS, IAM roles for workloads, synced secrets, secret detection in every pipeline, Wiz runtime security, and a corporate-network IP fence that self-heals daily from the official feed.
- Built GitLab CI/CD from lint to production: one image per commit promoted from dev to QA to production without rebuilds, one-click promotions, in-cluster end-to-end and load tests, and generated release notes with rollback pointers.
- Built a schema-first Node.js/TypeScript back end that turns 6 Kafka product-data streams (SAP material master, technical data, assets, relations) into a 3.7 million document MongoDB index, kept current by resumable backfill and hourly syncs.
- Delivered a bilingual (EN/DE) React/TypeScript app on the Siemens iX design system: product search with business-unit-scoped faceted filters, product detail with media galleries and relation views, and user and access management.
- Proved production readiness with in-cluster Playwright end-to-end tests, k6 load tests against a 2,000-user model showing around 6x capacity headroom, accessibility checks in CI, and architecture, capacity, and runbook documentation.
Technologies: Node.js, React, Apache Kafka, MongoDB Atlas, Amazon EKS, AWS Fargate, Kubernetes, Terraform, GitLab CI/CD, Microsoft Entra ID, Microsoft Graph API, OpenID Connect (OIDC), OAuth 2, DevSecOps, OpenAPI, REST APIs, Playwright, Grafana k6, Software Architecture, Technical Leadership, AWS WAF, AWS ALB, Amazon Elastic Container Registry (ECR), Amazon S3 (AWS S3), AWS Secrets Manager, AWS Systems Manager, Amazon CloudWatch, External Secrets, Wiz Cloud Security Platform, Docker, Vite, Vitest, Zod, i18next, SAP Integration, Role-based Access Control (RBAC), Single Sign-on (SSO), Load Testing, E2E Testing, Accessibility Testing, Kubectl, Microsoft Entra, Amazon, Integration, Back-end Architecture
Senior Software Architect & Lead Engineer
2026 - 2026
Woven by Toyota
- Owned the HD-map data platform of Woven by Toyota's autonomous-driving map team end to end, from architecture and backlog to delivery, ingesting NDS.Live HD-map releases from Tier-1 map suppliers into a lane-level PostGIS database on Amazon Aurora.
- Modeled lane geometry and connectivity, boundaries, landmarks, traffic rules, and ADAS attributes such as curvature, slope, and speed limits; built about 100 derived layers published via GeoServer/GeoNode (WMS/WFS) for route validation and map QA.
- Led the map-data workstream hands-on: turned production findings and design gaps into Jira epics, sequenced them with rollout/rollback plans, distributed work across the team, and defined a map-catalog API contract adopted by two downstream teams.
- Authored and delivered a multi-phase scaling roadmap (dependency-aware concurrent refreshes, 8-way sharding, table partitioning, extended statistics), each phase shipped as an independently revertible release with measured before/after results.
- Scaled the database from North America to Japan-sized releases: 291,000 map tiles, about 2.6 billion rows, and 400 GB of source data per release, schemas up to 2 TB, and 41-million-row materialized views, using hash sharding and table partitioning.
- Root-caused query-planner problems at billion-row scale: a centerline layer from 6+ hours to 6 minutes, a 9h44m refresh traced to a planner misestimate (one shard from 1h10m to 35s), and a published join exploding to 4.2B rows instead of 5 million.
- Evolved the ingestion pipeline through three generations: a manual Kubernetes runbook, GitHub Actions with OIDC-to-Vault credentials and zero static secrets, then a self-service control plane with a FastAPI/Django orchestrator and a React 19 UI.
- Ran every map release as isolated Kubernetes jobs with least-privilege access: verified downloads, 32-way parallel ingest in Go, memory-aware refresh, and publishing; resume-from-stage cut failure recovery from 2 hours to seconds.
- Ran the production Aurora Serverless v2 cluster in Terraform/Terragrunt: doubled capacity from 128 to 256 ACU, tuned database parameters for parallel workloads, and added in-region and cross-region PrivateLink plus cross-account S3 access.
- Resolved production incidents on the autonomous-driving critical path: an Aurora writer failover during a Japan refresh, hotfixed the same night by cutting memory demand from 1,536 GB to 96 GB, and a GeoNode crash traced to an external WMS client.
Technologies: Go, Python, React, FastAPI, Django, PostgreSQL, PostGIS, Amazon Aurora, Amazon Web Services (AWS), Kubernetes, Terraform, Terragrunt, Docker, Istio, GitHub Actions, HashiCorp Vault, Microsoft Entra ID, OpenID Connect (OIDC), GeoServer, GeoNode, HD Maps, Query Optimization, Software Architecture, Technical Leadership, Database Sharding, Database Partitioning, Materialized View, Incident Response, Vite, SQLAlchemy, Pytest, Testcontainers, Kustomize, AWS PrivateLink, Amazon S3 (AWS S3), AWS Secrets Manager, Amazon CloudWatch, Google Cloud Platform (GCP), Dagster, LakeFS, Bazel, JFrog Artifactory, Prometheus, OpenTelemetry, OGC (WMS/WFS), NDS.Live, Advanced Driver-assistance Systems (ADAS), Jira, Pandas, Data Engineering, Kubectl, OBJ Format, Microsoft Entra, Python 3, Amazon, Integration, Back-end Architecture
Senior Back-end & Platform Architect
2025 - 2026
Woven by Toyota
- Acted as a sole architect and code author of Toyota's HD-map delivery pipeline, embedded in a flat team: turned Tier-1 supplier map tiles into PostGIS layers published through GeoServer and GeoNode for autonomous-driving programs; numerous PRs across 5 repos.
- Removed 2 materialized-view refresh bottlenecks in the daily map pipeline by replacing costly PostGIS spatial joins with precomputed geohash keys: the largest (22.7 million rows) dropped from 2+ hours to around 5 minutes, another from 60 to 10 minutes.
- Eliminated around 6% tile loss in the daily pipeline by redesigning the Go ingestion service so the schema is prepared once and 8 Kubernetes pods then ingest tiles in parallel without conflicts, orchestrated by Dagster for reliable daily releases.
- Replaced a hardcoded list of materialized views with automatic discovery from the PostgreSQL catalog, ending paired cross-repository changes whenever a view was added or removed, and making the database schema the single source of truth.
- Built two reusable Python libraries, a GeoNode command-line tool, and a GeoServer REST client that the orchestration platform uses to trigger catalog updates and track async jobs; published via JFrog Artifactory with 85% test coverage.
- Rebuilt the PostgreSQL-to-GeoServer synchronization as a Django REST service with OIDC authentication and automatic token refresh, replacing a legacy XML integration with a lean JSON API for simpler, more reliable map publishing.
- Fixed a performance cliff in GeoNode catalog imports (around 350x faster) by querying GeoServer directly instead of per-layer security calls; added a spatial-index safety check that caught an unindexed 426 million row table before it could crash workers.
- Simplified pipeline orchestration by replacing heavyweight container wrappers with lightweight REST calls to the sync service, making every run leaner and easier to maintain; isolated credentials per environment with HashiCorp Vault.
- Designed secure cross-cluster and cross-account connectivity: Istio service-mesh policies for pipeline-to-GeoServer traffic and an AWS PrivateLink endpoint service for private, cross-account PostgreSQL ingestion into Aurora.
- Made deployments safely reversible: when a release stalls, GeoNode, GeoServer, and RabbitMQ roll back automatically on Kubernetes while Terraform state stays in sync with the cluster; added Prometheus monitoring across the sync layer.
Technologies: Go, Python, PostgreSQL, PostGIS, Amazon Aurora, Amazon Web Services (AWS), Amazon EKS, Kubernetes, Terraform, Terragrunt, Helm, Istio, Docker, Django, REST APIs, GeoServer, GeoNode, OGC (WMS/WFS), HD Maps, Geospatial Data Pipelines, Dagster, HashiCorp Vault, GitHub Actions, Prometheus, Platform Engineering, AWS PrivateLink, LakeFS, Bazel, RabbitMQ, SQLAlchemy, Cobra, Click, GeoFence, SLD, NDS.live, External Secrets, OAuth 2.0 / OIDC, Azure Active Directory, JFrog Artifactory, OpenTelemetry, Testcontainers, Materialized View, Query Optimization, SQL, DevOps, Python 3, Amazon, Back-end Architecture
Fractional CTO & Founding Engineer
2025 - 2025
Audio Armor LLC
- Served as a fractional CTO and founding engineer, I took Audio Armor from zero code and zero infrastructure to a live B2C/B2B audio-protection platform, owning requirements, architecture, development, infrastructure, and delivery end-to-end.
- Worked directly with the founder and investor, a musician with deep audio-industry knowledge, to analyze the market need, gather requirements, and define both the product and the way it would be built.
- Built the complete MVP across dev, staging, and production in just four weeks: a Next.js front end and a Python/FastAPI back end running proprietary algorithms for audio protection, watermarking, stem protection, and AI protection.
- Designed a serverless, event-driven AWS architecture: Lambda for audio processing, SQS queues for asynchronous jobs, ECS for containerized services, DynamoDB for data, and S3 with CloudFront for files, all provisioned with Terraform.
- Optimized the Python audio-processing libraries and the proprietary algorithms for fast, high-quality audio processing with minimal latency.
- Built for scale with microservices, asynchronous processing, and cloud-native patterns, so the platform can handle high volumes of concurrent audio-processing requests.
- Integrated Auth0 authentication and Stripe subscriptions and payments, with webhook handling for B2C and B2B plans, giving the business a working monetization model from launch.
- Set up GitLab CI/CD with automated deployments across dev, staging, and production, plus Route 53 and CloudFront delivery, enabling rapid iteration and reliable releases as the product evolved.
- Led technical development as the team grew from a solo developer to five people after a successful investment round, establishing the engineering practices and architectural guidelines the team built on.
- Onboarded the acquiring company's engineering team in Poland on the platform's architecture, infrastructure, and codebase following its sale, ensuring they could operate it independently and completing a clean handover.
Technologies: Python, Artificial Intelligence (AI), Amazon Web Services (AWS), Next.js, FastAPI, React, AWS Lambda, Amazon Simple Queue Service (SQS), Amazon DynamoDB, Amazon S3 (AWS S3), Amazon CloudFront, Terraform, GitHub Actions, Auth0, Stripe, Serverless Architecture, Microservices, Audio Processing, Software Architecture, Technical Leadership, Amazon Route 53, Event-driven Architecture, Digital Watermarking, Webhooks, SaaS, Requirements Analysis, Product Management, AWS Step Functions, Amazon, Back-end Architecture
Cloud Migration Architect
2025 - 2025
Siemens
- Migrated around 10 TB of live documents used by around 100 applications and services from on-prem Windows file servers to AWS EFS in 3 weeks, as part of transitioning Siemens' PDA application portfolio fully onto AWS, serving as the sole designer and implementer.
- Treated application compatibility as the hard constraint: preserved every directory structure and mount path, so every dependent application and service kept working on AWS EFS without a single code change.
- Built a Python sync tool on the AWS SDK (boto3) that copied data from Windows file servers into Amazon S3 and on into EFS inside the private VPC, using timestamps so each incremental round moved only new and changed files.
- Ran staged incremental sync rounds while the applications stayed in service, then completed the final cutover in a single weekend night agreed with stakeholders, with no service interruption for users.
- Migrated file permissions and ownership with scripts across the Windows file servers and the self-built AWS environment, so users and services kept exactly the access they had before the move.
- Verified the migration with automated checks and hands-on testing alongside the application owners' developers and stakeholders, confirming each service worked on the new storage before the on-prem servers were retired.
- Mounted EFS into the Docker-based services over NFS and trained the application owners' developers to do the same for their own services; EFS has been the platform's shared document store ever since.
- Configured EFS for production: encryption, AWS Backup with a tested restore, and lifecycle rules that move rarely used files to the Infrequent Access tier, lowering storage cost without affecting active files.
- Retired the on-prem file servers and brought the data layer fully onto AWS, removing the platform's last on-prem dependency and completing the storage side of the portfolio's move to the cloud.
- Laid the groundwork for the platform's later infrastructure automation: with storage on AWS, full blue-green rebuilds no longer depend on any on-prem system, which later made around 30-minute, zero-downtime environment rebuilds possible.
Technologies: Amazon Web Services (AWS), Amazon EFS, Cloud Migration, Database Migration, Network File System (NFS), Docker, Docker Swarm, Amazon Virtual Private Cloud (VPC), Hybrid Cloud Infrastructure, AWS Cloud Architecture, Cloud Infrastructure, DevOps, Bash, Storage, File Systems, Networking, Migration Planning, Cutover Planning, Zero-downtime Deployment, Python, Boto3, Amazon S3 (AWS S3), Windows Server, Cost Reduction & Optimization (Cost-down), Stakeholder Management, Technical Training, AWS RDS MySQL, Python 3, Amazon
Cloud Infrastructure Architect & DevOps Lead
2025 - 2025
Siemens
- Modernized the infrastructure of Siemens Türkiye's PDA platform as the sole architect and engineer, migrating approximately 60 production web apps to AWS. These included multi-country portals serving multiple Siemens countries, which were previously operated on hand-built, manual servers.
- Designed and built a complete Terraform platform from scratch (170+ managed AWS resources) that turned a manually managed Docker Swarm estate into an automated, self-healing, zero-downtime environment inside an isolated VPC with no internet access.
- Solved the platform's biggest risk: Siemens ships a new security-hardened server image almost weekly, and each migration took a full day of manual work; blue-green automation cut it to around 30 minutes, zero-downtime, one-command operation.
- Automated the full blue-green cycle with Terraform workspaces: detects new Siemens images, clones them despite restricted permissions, provisions a parallel environment, redeploys every app, and switches traffic atomically with instant rollback.
- Consolidated the estate by migrating roughly half of the applications that had never run in the cluster onto the new platform, onboarding each to the shared registry and CI/CD without ever touching the live legacy environment.
- Added worker auto-scaling from 1 to 8 nodes on CPU and memory metrics, encrypted private Docker registries per environment, stable manager identities, and private DNS that removed every hardcoded IP from apps and pipelines.
- Built a serverless API edge: per-app REST API Gateways for 13 apps behind a shared custom domain, private links into the internal load balancer, Lambda JWT authorizers, and WAF, plus path-based routing for ~50 apps.
- Took observability from none to real-time Prometheus and Grafana dashboards with tiered alerting: critical alerts to Microsoft Teams and SMS via API Gateway, Lambda, and SNS, and scheduled maintenance that stays correct after blue-green switches.
- Modernized GitLab CI/CD for around 50 application repositories with shared pipeline templates, moving them from hardcoded-IP deployments to the DNS-based platform, with one configuration as the single source of truth for Terraform and deployments.
- Made the platform operable by any team member without SSH or Terraform knowledge: an interactive operator CLI and web UI for status, image drift detection, guided blue-green switches, deploys, and logs; disaster recovery went from hours to minutes.
Technologies: Amazon Web Services (AWS), Terraform, Infrastructure as Code (IaC), Docker, Docker Swarm, Amazon EC2, AWS Auto Scaling, Amazon Virtual Private Cloud (VPC), Amazon API Gateway, AWS Lambda, AWS ALB, Amazon Route 53, Amazon CloudWatch, AWS WAF, GitLab CI/CD, Prometheus, Grafana, Blue-green Deployment, Zero-downtime Deployment, AWS Cloud Architecture, DevOps, Site Reliability Engineering (SRE), Bash, Node.js, Amazon S3 (AWS S3), Amazon Simple Notification Service (SNS), AWS Secrets Manager, AWS Systems Manager (SSM), Amazon EventBridge, AWS IAM, AWS Certificate Manager (ACM), Docker Registry, Express.js, WebSockets, Linux, Monitoring, Monitoring & Alerting, Disaster Recovery (DR), AWS RDS MySQL, Python 3, Amazon
Software Architect, Full-Stack Developer & Product Owner
2025 - 2025
Siemens
- Modernized Siemens' Leadtogether, an employee lead-generation incentive platform credited with 2,500+ leads and around EUR 15 million in won orders, where field engineers capture customer opportunities and earn a bonus through a governed approval workflow.
- Extracted the product, live in Türkiye since 2018, from a legacy mobile-portal monolith into standalone back-end and front-end applications, replacing per-country databases and heavy external dependencies with a clean, self-contained architecture.
- Delivered the extraction, full-stack modernization, and multi-tenant re-architecture in 2 weeks through an AI-assisted engineering workflow, owning every architecture and product decision end to end, from domain model to deployment.
- Rebuilt the back end on Java 25 and Spring Boot 4, running on Docker Swarm behind a dedicated AWS API Gateway whose Lambda JWT authorizer validates Siemens ID single sign-on tokens (OAuth 2.0) before any request reaches the service.
- Rebuilt the front end as a React, Ionic, and TypeScript single-page app served from Amazon S3 and CloudFront, giving employees a modern web and mobile experience for capturing leads in the field and following them through approval.
- Made the platform fully multi-tenant: each organization runs its own tenant with country and business-unit teams, currencies, bonus multipliers, eligibility policy, and approval committees; leads flow across teams while creators keep the reward.
- Consolidated the per-country legacy databases into a single multi-tenant MySQL schema on Amazon RDS and cut external dependencies down to identity and mail, so onboarding a new country became configuration instead of a code fork.
- Owned the product side: designed the workflow and governance model end to end, from lead capture through coordinator and sales review, two-step service-line approval, and an optional country committee to the final bonus payout.
- Rolled out tenants across 10 countries: Türkiye, a seven-country Gulf hub, Australia, and New Zealand; created an executive marketing deck presenting the platform's value to leadership in further candidate countries.
- Produced a set of narrated, role-based product videos and an in-app video guide catalog filtered by each user's role, so employees, coordinators, and approvers in every new country can onboard themselves without training sessions.
Technologies: Java 25, Spring Boot 4, MySQL, Amazon RDS, React, Progressive Web Applications (PWAs), Ionic 8, TypeScript, Amazon Web Services (AWS), AWS Lambda, Amazon API Gateway, Amazon S3 (AWS S3), Accessibility Testing, Amazon CloudFront, JSON Web Tokens (JWT), OAuth 2, Single Sign-on (SSO), Docker Swarm, Multitenancy, Legacy Application Modernization, Database Migration, Software Architecture, Product Ownership, Vite, Docker, REST APIs, Role-based Access Control (RBAC), Workflow Design, IT Product Management, Product Marketing, AWS RDS MySQL, Python 3, Amazon
Authentication & Authorization Expert
2025 - 2025
Robert Hommes, Amsterdam Holland
- Created an Auth0 tenant and an Auth0 regular web application client.
- Implemented Auth0 post-login triggers with Node.js, creating OpenID IdToken custom claims.
- Implemented Auth0 IdToken authentication and authorization flows, including organizations, roles, and permissions.
- Implemented machine-to-machine authentication and authorization flows, including permissions.
- Designed and developed Python FastAPI Rest APIs, used FastAPI security, and integrated with Auth0. Implemented login APIs and authorization layers. Used Auth0 JWKS to validate JWT tokens, authorization based on role and permission validations.
- Implemented Auth0 logout and Auth0 reset ticket flows. Implemented Portman collections for E2E testing. Achieved these in 40 hours.
Technologies: Auth0, Auth0 API, Auth0 Management API v2, M2M, Authorization, Authentication, Security, Python, OpenAI, JSON, RESTFul APIs, JSON Web Tokens (JWT), Artificial Intelligence (AI), AI Virtual Assistant, Large Language Models (LLMs), AI Agents, AI Integration, ChatGPT, Asynchronous Programming, Data Extraction, Data Structures, Prompt Engineering, Retrieval-augmented Generation (RAG), AI Chatbots, Audio Processing, Advisory, Python 3
Cloud Database Migration Architect
2024 - 2025
Siemens
- Worked in a team migrating the legacy Oracle database behind Siemens' PDA platform to Amazon RDS for MySQL, personally owning the migration of a subset of the application portfolio end to end, from schema conversion to cutover.
- Converted the schemas of the assigned applications from Oracle to MySQL, mapping engine-specific structures and data types to an equivalent design on Amazon RDS so the migrated data kept its integrity and relationships.
- Ported the assigned applications' SQL from the Oracle dialect to MySQL, updating their queries so they ran correctly against the new database without functional changes for users.
- Migrated and validated the assigned applications' data for completeness and correctness, then moved them to production in a controlled, planned cutover to keep disruption for users to a minimum.
- Helped retire the legacy Oracle database, eliminating its license costs, and moved the data onto managed Amazon RDS with automated backups, patching, and monitoring, reducing operational effort for the team.
- Aligned the data layer with the rest of the AWS-hosted application portfolio, so the database now runs under the same managed, automated operating model as the platform's other cloud services.
Technologies: Oracle Database, MySQL, Amazon RDS, Amazon Web Services (AWS), Database Migration, Data Migration, Cloud Migration, SQL, Database Schema Design, Data Validation, Cost Reduction & Optimization (Cost-down), AWS Cloud Architecture, AWS DevOps, Database Administration (DBA), Backup & Recovery, Database Monitoring, Migration Planning, Cutover Planning, Legacy System Modernization, IT Security, IT Product Management, IT, AWS RDS MySQL, Python 3, Amazon Elastic Block Store (EBS), Amazon
Full-stack Mobile Engineer & Architect
2024 - 2025
KickBack Points LLC, USA
- Developed KickBack Points' loyalty platform from scratch as the sole developer, creating an Android app for Verifone payment terminals. This system allows aviation customers to swipe loyalty cards when purchasing jet fuel to earn points, along with its supporting Node.js back end.
- Analyzed requirements and defined the scope with the client's architect, then proposed the architecture and technology stack for the terminal app and back end, which the client adopted.
- Worked with Verifone's platform team to use the terminal's native capabilities, such as card reading and receipt printing, on the Verifone T650C Android POS device.
- Wrote custom Capacitor plugins in Java that wrap Verifone's payment SDK and the socket.io Java client, giving the Ionic/React app direct access to card reads, printing, and real-time messaging.
- Built the terminal app with Ionic 8, React 18, and Capacitor, delivering several loyalty use cases with a modern, touch-friendly interface designed for quick use at the point of sale.
- Built a Node.js back end that keeps real-time socket.io connections with every terminal and handles loyalty operations such as issuing points, checking balances, and downloading terminal configuration.
- Integrated the back end with the client's configuration and loyalty services over raw TCP sockets, bridging their protocol and the terminals' real-time socket.io channel.
- Generated receipts on the server and delivered them to terminals as Base64 images for printing, keeping receipt layouts managed centrally instead of hard-coded on each device.
- Deployed the back end to AWS ECS Fargate with AWS CDK as infrastructure as code, and automated blue-green releases through GitHub Actions for zero-downtime updates.
- Covered the back end with unit tests and built small native Kotlin Android apps to test terminal commands against the Verifone Java SDK before integrating them into the main app.
Technologies: TypeScript, React, Ionic, Serial Communication, TCP/IP, Payment APIs, Java 21, Capacitor, WebSockets, Node.js, AWS Cloud Development Kit (CDK), Amazon Elastic Container Service (ECS), AWS Fargate, AWS WAF, Amazon EC2, GitHub, GitHub Actions, Docker, Amazon Elastic Container Registry (ECR), AWS Secrets Manager, JSON, Infrastructure as Code (IaC), RESTFul APIs, JSON Web Tokens (JWT), Progressive Web Applications (PWAs), ECS, Asynchronous Programming, AWS ALB, Autoscaling, Data Extraction, Data Structures, AWS Cloud Architecture, Leadership, Mobile First, Advisory, Requirements Analysis, Solution Architecture, Hybrid Mobile Apps, Mobile App Development, Payment Terminals, Point of Sale, Amazon
Mobile App Developer
2024 - 2024
Mario Hehne und Fabian Naumann GbR, Germany
- Took over an existing Angular 18 and Ionic 7 application, addressing leftover defects and improving poor design elements without a formal handover process.
- Compiled Android and iOS apps, resolving authentication issues with KeyCloak to ensure secure user access.
- Developed comprehensive documentation for the application, enhancing maintainability and facilitating smoother onboarding for future developers.
- Optimized API request handling to address performance issues and eliminate numerous bugs, while working extensively with various GIS vector data to enhance product functionality.
Technologies: JavaScript, Angular, Ionic, TypeScript, Mobile Apps, Mobile App Development, Offline-first Development, Offline Data Synchronization, Geodatabases, Geospatial Data, Offline Maps, NoSQL, PostGIS, PostgreSQL, JSON, RESTFul APIs, JSON Web Tokens (JWT), Progressive Web Applications (PWAs), Asynchronous Programming, IndexedDB, Data Extraction, Data Structures, Django, PWA or Progressive Web Apps, Mobile First, Advisory
Software & Solution Architect
2023 - 2024
Siemens
- Architected where2buy.siemens.com, Siemens' global where-to-buy platform that publishes distributors' stock so customers can find which partners carry the products they need, live in 20 countries, including the USA, Germany, Poland, and Brazil.
- Served as software and solution architect for a team of 2 back-end and 2 front-end developers and a scrum master, advising Siemens business units and stakeholders worldwide on bringing their markets and data onto the platform.
- Designed a multi-tenant platform with three portals: a public site for end users, a partner portal for distributors, and an internal admin portal; each tenant has its own admins, distributors, managers, and users.
- Integrated Siemens' product data sources, covering around 10 million products with their images, documents, and attributes, and scanned the portfolio per country and region to keep every market's catalog current.
- Built a two-way Snowflake integration: distributors and their stock levels flow from Snowflake into where2buy, and distributors onboarded through where2buy's own channels flow back to Snowflake for company-wide use.
- Created self-service SFTP onboarding on AWS Transfer Family: each partner provisions its own S3-backed SFTP location and credentials and starts sharing stock without waiting on Siemens.
- Opened every channel partners need to share stock: REST API integrations, automated SFTP feeds, and Excel upload or paste in the partner portal, plus a Power BI integration for reporting.
- Modernized the platform in 2026 by upgrading from Java 8 and Spring Boot 2.7 to Java 25 and Spring Boot 4.0. Transitioned the system from EC2-hosted systemd services to Docker Swarm on AWS. Transitioned the system from EC2-hosted systemd services to Docker Swarm on AWS.
- Operated the platform with a main Spring Boot service and two Node.js services on Docker Swarm, alongside three Python services running as Kubernetes CronJobs, utilizing MySQL behind Amazon API Gateway and CloudFront.
- Stayed hands-on alongside the team: personally built the admin portal (Angular, Spring Boot) and the SFTP integration service, and automated builds and deployments with GitLab CI/CD.
Technologies: Java, Spring Boot, Spring Data JPA, Python, Node.js, Angular, MySQL, Snowflake, Power BI, REST APIs, Amazon Web Services (AWS), AWS Transfer Family, SFTP, Amazon S3 (AWS S3), Amazon API Gateway, Amazon CloudFront, Amazon Cognito, Single Sign-on (SSO), Docker, Docker Swarm, Amazon EKS, GitLab CI/CD, ETL, Data Integration, Multitenancy, Legacy Application Modernization, Solution Architecture, Software Architecture, Stakeholder Management, Technical Leadership, Firebase Realtime Database, DocumentDB, Firebase, Python 3, Amazon
Full-stack Developer & Architect
2023 - 2024
Coino.com
- Built an order book management system (OBMS) from scratch for a crypto exchange platform in collaboration with a talented colleague. The OBMS allows multi-session integration between an integral liquidity provider (LP) and the exchange platform.
- Enabled the OBMS to provide near real-time processing performance, simultaneously handling 200 trading pairs on a regular server with a 3-4 millisecond processing speed and 300 trading pairs in 8-10 milliseconds.
- Created a Grafana metrics dashboard for the OBMS. Integrated Telegram for the alerts and a Watchdog engine that constantly audits the exchange for expired and stuck open orders, resolving issues where necessary.
- Configured and created bots in the OBMS to perform buy-and-sell operations executing the given algorithms.
- Handled significant reports and modules such as price depth configuration, hedging, bot operations, exchange trading pairs, LP symbols and prices, tickers, the health dashboard, exchange account and user management, and LP session management.
- Developed a separate service for performance measurement with TestBench to simulate mock LP and exchange. It produces market data traffic against the OBMS and captures the output.
- Profiled, measured, and improved the OBMS processing speed under the traffic.
- Used a cutting-edge tech stack and cost-effective architectural design for the OBMS, which includes Java 21 with virtual threads, Helidon, Node.js with Knex.js, Go, SQLite, NATS, React with Ionic, Terraform, GitHub Actions, Amazon ECR, and QuickFIX.
Technologies: Java 21, Virtual Threads, Node.js, Knex.js, Go, SQLite, React, Ionic 7, Progressive Web Applications (PWAs), NATS, Docker Compose, Terraform, GitHub Actions, Telegram Messenger API, Grafana, Prometheus, Algorithms, Helidon, QuickFIX, Amazon Elastic Container Registry (ECR), Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Tailwind CSS, API Integration, Back-end, Agile, Scrum, Architecture, Jest, Express.js, Responsive Web Design (RWD), JPA, PWA, Databases, JavaScript MVC, SSL Certificates, Vite, GitHub, Authentication, Authorization, Front-end Development, CSV, Data Visualization, Amazon CloudWatch, Amazon Elastic Container Service (ECS), WebSockets, API Design, SCSS, Capacitor, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Database Structure, Agile Software Development, OpenAI API, Functional Programming, AWS Command Line Interface (CLI), TypeScript 3, IntelliJ IDEA, REST, Mobile Development, AWS Certificate Manager, Cloud, Cloud Platforms, DevOps, AWS Secrets Manager, Mobile Apps, Responsive UI, Web UI, JSON, Jira, RESTFul APIs, JSON Web Tokens (JWT), CTO, Asynchronous Programming, Data Extraction, Data Structures, AWS Cloud Architecture, PWA or Progressive Web Apps, Mobile First, Advisory, SaaS Design, Amazon
Tech Lead & Full-stack Mobile App Developer
2023 - 2023
Prudential
- Designed new modules for the TellMe app based on the company's business unit requirements. Prudential Asia's HR unit is the product owner of this app, where company employees give feedback to each other.
- Handled DevSecOps scan reports using Nexus OSS, Aqua Security, dynamic application security testing with Burp Suite, and static application security testing with Fortify. Managed meetings between IT experts, DevSecOps experts, and customer groups.
- Managed user acceptance tests. Early life support is given during product launch.
Technologies: Ionic, Angular, Cordova, DevSecOps, Azure, Spring Boot, Microsoft Intune, SFTP, Workday, User Acceptance Testing (UAT), Bitbucket, Jenkins, Jenkins Pipeline, Azure Kubernetes Service (AKS), Front-end Architecture, Figma, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), User Experience (UX), JPA, PWA, Databases, JavaScript MVC, Kubernetes, Amazon RDS, Authentication, Single Sign-on (SSO), Authorization, Android, iOS, Front-end Development, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Technical Leadership, Database Structure, Agile Software Development, OAuth, Angular CLI, TypeScript 3, IntelliJ IDEA, REST, Mobile Development, Cloud, Cloud Platforms, DevOps, Mobile Apps, Responsive UI, Web UI, IT Consulting, JSON, RESTFul APIs, JSON Web Tokens (JWT), Progressive Web Applications (PWAs), Sass, Asynchronous Programming, Data Extraction, Data Structures, Leadership, IT Security, PDF, PWA or Progressive Web Apps, Advisory, SaaS Design, Amazon
Tech Lead & Full-stack Developer
2022 - 2023
Prudential
- Created Workday and SFTP integration. Implemented SSO authentication.
- Enhanced existing product functionalities and created new modules.
- Supported the user acceptance tests, collected new requirements from the company's business units, and further covered these requirements.
Technologies: Ionic, User Acceptance Testing (UAT), Angular, Cordova, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), User Experience (UX), JPA, PWA, Databases, Kubernetes, Amazon RDS, Authentication, Authorization, Android, iOS, Front-end Development, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Database Structure, Agile Software Development, OAuth, Angular CLI, TypeScript 3, IntelliJ IDEA, REST, Mobile Development, Cloud, Cloud Platforms, DevOps, Mobile Apps, Responsive UI, Web UI, IT Consulting, JSON, RESTFul APIs, JSON Web Tokens (JWT), Progressive Web Applications (PWAs), Sass, Asynchronous Programming, Data Extraction, Leadership, IT Security, PDF, PWA or Progressive Web Apps, Advisory, SaaS Design
Full-stack Java Developer
2021 - 2023
MUFG Investor Services
- Developed features using PrimeNG and Angular 14 for a finance web application portal. Fixed bugs, built unit tests for each change using Jasmine and Karma, and created complex web pages.
- Created features on multiple Java 11 and Spring Boot microservices. Fixed bugs, developed unit and integration tests, and actively reviewed Java code from teammates.
- Resynced an Angular project using its forked version. Created the GitLab rebase branch from a forked repository, using the rebase branch as an upstream on the other project and managing a huge code propagation.
- Contributed to migrating and reimplementing the old Flash-based products' front and back-end parts, which includes multitenancy, as new single-page web applications and Java Spring Boot-based modern microservices.
Technologies: Java, Spring Boot, Apache Maven, GitLab, Microservices, SSL, Production Support, Angular, Jenkins, Oracle, Amazon Web Services (AWS), MongoDB, Spring Data MongoDB, ActiveMQ, Spring Data JPA, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, API Integration, Back-end, Agile, Scrum, Architecture, Responsive Web Design (RWD), JPA, Databases, JavaScript MVC, Datadog, Amazon RDS, Authentication, Authorization, Front-end Development, CSV File Processing, Amazon CloudWatch, Java Message Service (JMS), HTML5, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Database Structure, Agile Software Development, OpenAI API, AWS Command Line Interface (CLI), Angular CLI, TypeScript 3, IntelliJ IDEA, REST, Microservices Architecture, Cloud, Cloud Platforms, Responsive UI, Web UI, IT Consulting, AG Grid, Spring Microservice, JSON, Finance APIs, Jira, RESTFul APIs, JSON Web Tokens (JWT), Jasmine, Sass, Asynchronous Programming, MongoDB Atlas, Finance, AWS Cloud Architecture, PDF, Apache POI, Keycloak, Functional Reactive Programming
Tech Lead & Full-stack Mobile App Developer
2022 - 2022
Prudential
- Redesigned and developed the TellMe app, an internal application used by employees to provide feedback to each other.
- Developed web and mobile applications. Released and published the iOS and Android apps via the Microsoft Intune server. Deployed the web app in the Azure Kubernetes Service environment via Jenkins CI/CD automation and created Jenkins CI/CD scripts.
- Contributed to the back-end implementation, developed Java services, and designed front and back-end architecture.
- Documented the product and prepared high-level design documents.
Technologies: Ionic, Angular, Cordova, Java, Spring Boot, DevSecOps, Vulnerability Assessment, Jenkins, Azure, Mobile App Development, Web App Development, SFTP, Front-end Architecture, Figma, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), User Experience (UX), JPA, PWA, Databases, JavaScript MVC, Kubernetes, Amazon RDS, Authentication, Authorization, Android, iOS, Front-end Development, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Database Structure, Agile Software Development, Angular CLI, TypeScript 3, IntelliJ IDEA, REST, Mobile Development, Cloud, Cloud Platforms, DevOps, Mobile Apps, Responsive UI, Web UI, IT Consulting, JSON, RESTFul APIs, JSON Web Tokens (JWT), Progressive Web Applications (PWAs), Sass, Leadership, IT Security, PWA or Progressive Web Apps, SaaS Design
Software Architect & Lead Back-end Engineer
2021 - 2022
Siemens
- Designed and built the backend of digionenow.com, Siemens' public-facing B2B partner and client portal, as part of a small team, and rolled it out to partners and customers in Türkiye, Brazil, and Malaysia.
- Delivered the portal's core modules: product and stock search, campaigns, a partner finder, and partner trainings, giving Siemens partners and their customers a single self-service portal.
- Designed the AWS network architecture: a public-facing portal with back-end services isolated in a strictly private VPC subnet, connected over AWS VPN to the Siemens intranet for secure access to on-prem SAP services.
- Implemented the back-end services in Java/Spring Boot, Node.js, and Python, bringing on-prem SAP data together with cloud services behind Amazon API Gateway.
- Secured partner and customer sign-in using Amazon Cognito user pools and sent transactional emails through Amazon SES, maintaining identity and messaging on managed AWS services.
- Stored portal data in MySQL with Spring Data JPA and in Amazon DynamoDB, and served the Angular front end through Amazon S3, CloudFront, and Route 53.
- Provided secure SFTP data exchange for partner integrations on AWS Transfer Family, without running or patching any file servers.
Technologies: Java, Spring Boot, Spring Data JPA, Node.js, Python, Angular, MySQL, Amazon DynamoDB, Amazon Web Services (AWS), Amazon Virtual Private Cloud (VPC), AWS VPN, Amazon API Gateway, Amazon Cognito, Amazon CloudFront, Amazon S3 (AWS S3), Amazon Simple Email Service (SES), Amazon Route 53, AWS Transfer Family, SFTP, SAP Integration, Serverless Architecture, Software Architecture, AWS Cloud Architecture, Docker, Network Security, AWS RDS MySQL, Restify, Amazon
Full-stack Angular & Node.js Developer
2021 - 2022
Cleardoc Inc. (dba OPENREEL)
- Implemented back-end features to the remote video creation product, creating REST and Socket.io APIs with NestJS and Socket.io, MySQL with Node.js and Sequelize, and video transcoding APIs with Redis and Bull.
- Worked on the web-based remote video capture product—a conferencing platform where participants join and capture 4K video remotely. Several scenarios are implemented for browser-based, end-to-end testing using Cypress.io and Puppeteer.
- Developed UI features using Angular 12 and fxFlex layouts.
Technologies: Angular, Node.js, Socket.IO, Sequelize, NestJS, Redis, MySQL, Amazon Web Services (AWS), Cypress, Puppeteer, NgRx/store, Full-stack, Web Development, Java 8, SQL, TypeScript, Test-driven Development (TDD), Front-end, Videos, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, Twilio, API Integration, Back-end, Agile, Scrum, Architecture, Express.js, Video Processing, Responsive Web Design (RWD), JPA, Google Cloud Platform (GCP), Databases, JavaScript MVC, Sentry, Amazon RDS, GitHub, Authentication, Single Sign-on (SSO), Authorization, Front-end Development, CSV, Amazon CloudWatch, HTML5, API Design, Video Streaming, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Redis Cache, Database Structure, Agile Software Development, AWS Command Line Interface (CLI), Angular CLI, Angular Material, IntelliJ IDEA, REST, Microservices Architecture, Cloud, Cloud Platforms, Responsive UI, Web UI, NgRx, JSON, Jira, RESTFul APIs, JSON Web Tokens (JWT), AWS Cloud Architecture, Twilio API, Amazon
Angular Front-end Developer
2020 - 2022
GPSENGINE
- Redesigned the PHP-based old portal as a new responsive Angular portal.
- Displayed vehicles and animated vehicle movement histories using Google Maps.
- Used an Apollo client for consuming GraphQL-based APIs.
Technologies: Angular, Apollo, GraphQL, Google Maps, RxJS, TypeScript, Web Development, Front-end, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, CI/CD Pipelines, JavaScript, API Integration, Back-end, Agile, Scrum, Architecture, Responsive Web Design (RWD), JavaScript MVC, GitHub, Authentication, Authorization, Google Maps API, Front-end Development, CSV, Data Visualization, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Angular CLI, IntelliJ IDEA, REST, Microservices Architecture, Bootstrap 4, Responsive UI, Web UI, Logistics, JSON, Jira, RESTFul APIs, JSON Web Tokens (JWT)
Full-stack Angular & Java Developer
2021 - 2021
E4 Logics
- Developed an Angular project with a PrimeNG Poseidon theme and Angular 11, creating several complex pages following a responsive design. Used Jasmin and Karma for unit testing.
- Built back-end services with Spring Boot and Java 11. Financial data is processed with PostgreSQL, and Postman is used for end-to-end testing.
- Created a CI/CD pipeline and a quality system for testing. Angular and back-end services are deployed to AWS.
Technologies: PrimeNG, Material Design, Java 11, Spring Boot, PostgreSQL, Amazon S3 (AWS S3), Full-stack, Web Development, Java 8, Angular, SQL, TypeScript, Front-end, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, JavaScript, Back-end, Agile, Scrum, Responsive Web Design (RWD), JPA, Databases, JavaScript MVC, Amazon RDS, SSL Certificates, Authentication, Authorization, Front-end Development, Amazon CloudWatch, HTML5, API Design, Amazon CloudFront, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Database Structure, Agile Software Development, AWS Command Line Interface (CLI), Angular CLI, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms, DevOps, Bootstrap 4, Responsive UI, Web UI, JSON, Jira, RESTFul APIs, JSON Web Tokens (JWT), Sass
Full-stack Developer & Serverless Architect
2020 - 2020
Siemens
- Developed a Siemens B2B web portal on AWS with a self-service sign-up flow in which business customers register with their company details, including tax number and tax office.
- Automated company verification at sign-up: a serverless Node.js service checks each applicant's tax number and tax office against the Turkish Revenue Administration's public portal while they register.
- Used Puppeteer with headless Chrome to query the government portal programmatically, so every registration was verified automatically instead of relying on manual lookups.
- Deployed the verification service on AWS Lambda behind Amazon API Gateway, a fully serverless setup that scales with sign-up traffic and runs at near-zero cost between registrations.
- Helped ensure that only legitimate, registered businesses could complete sign-up, protecting the quality of Siemens' B2B customer data from the first step of onboarding.
Technologies: Node.js, JavaScript, Puppeteer, AWS Lambda, Amazon API Gateway, Amazon Web Services (AWS), Serverless Architecture, Web Scraping, REST APIs, Automation, Full-stack Development, AWS RDS MySQL
Java Expert
2020 - 2020
Ride2go.com (owned by Fahrgemeinschaft.de GmbH)
- Contributed to developing the ride2go.com ridesharing platform, a progressive web app with Ionic and Angular. I embedded it into different portals and implemented several features and bug fixes during my 10-month engagement.
- Used GitHub for issue tracking and preparing pull requests.
- Embedded ride2go.com responsively in several portals using iFrame.
Technologies: Ionic 3, Angular, React, Gatsby, Spring Boot, Docker, Mobile App Development, Java 8, TypeScript, Front-end, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, JavaScript, API Integration, Back-end, Agile, Scrum, SDKs, Responsive Web Design (RWD), JPA, PWA, Databases, JavaScript MVC, GitHub, Authentication, Authorization, Front-end Development, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Database Structure, Agile Software Development, OpenAI API, Angular CLI, IntelliJ IDEA, REST, Mobile Development, Mobile Apps, Responsive UI, Web UI, JSON, RESTFul APIs, JSON Web Tokens (JWT), Sass, PWA or Progressive Web Apps
Full-stack Software Developer and Architect
2019 - 2019
Pinsoft
- Built a middleware layer that exposed a legacy, telnet-based airline ticketing system as a modern REST API, supporting flight booking, cancellation, and paginated queries by translating telnet sessions into structured Java data.
- Designed and developed, with a colleague, a flight-disruption management web app for an airline's intranet that handles disrupted passengers' reservations (PNRs) automatically, or manually with the help of interactive SVG visualizations.
- Integrated another team's disruption-solving algorithm and kept front end and back end work moving in parallel through mock REST services in Angular and Swagger-documented APIs for the back-end team.
Technologies: Snap.svg, Swagger, Bootstrap, Angular, GSON, Telnet Protocol, RESTful Services, Spring Boot, Full-stack, Java 8, SQL, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, JavaScript, Back-end, Agile, Scrum, Architecture, Databases, Front-end Development, API Design, Thymeleaf, Back-end Development, System Architecture, Angular Material, IntelliJ IDEA, REST, Responsive UI, Web UI, JSON, RESTFul APIs, JSON Web Tokens (JWT)
Full-stack Software Developer and AWS Architect
2018 - 2019
Siemens
- Designed and built Siemens' DiGi Partner platform from scratch as the architect of a four-person team, creating web portals and iOS and Android apps for Siemens partners and their customers. The platform was initially launched in Türkiye and subsequently rolled out to Russia, Italy, and Brazil.
- Delivered a broad module set: partner and user management, SAP stock queries and stock sharing, partner performance dashboards, order and logistics tracking, price lists, and special-price requests for projects.
- Added partner engagement features: sales campaigns, trainings, online support, marketing videos, a shopping catalog, a news feed, surveys, and email and mobile push notifications.
Technologies: SAP, VPN, Amazon Virtual Private Cloud (VPC), Amazon EC2, Load Balancers, AWS Lambda, Amazon Cognito, Amazon Cognito User Pools, API Gateways, Amazon Route 53, Amazon CloudFront CDN, Amazon S3 (AWS S3), Amazon Web Services (AWS), MySQL, Spring Boot, Ionic 3, Bootstrap, Angular, Full-stack, Amazon API Gateway, Java 8, SQL, Cordova, TypeScript, Mobile, REST APIs, JSON REST APIs, HTML, Spring Data JPA, Front-end Architecture, APIs, AWS SDK, Amazon Simple Queue Service (SQS), Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, Google Cloud Platform (GCP), PWA, Databases, Amazon Simple Notification Service (SNS), Amazon RDS, SSL Certificates, Web Scraping, Authentication, Single Sign-on (SSO), Authorization, Android, iOS, Google Maps API, Front-end Development, CSV, Amazon CloudWatch, HTML5, API Design, Amazon CloudFront, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Order Management, Auth0, Auth0 API, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Technical Leadership, Database Structure, Agile Software Development, OAuth, Apple Push Notifications, Zuul, AWS Command Line Interface (CLI), Angular CLI, IntelliJ IDEA, REST, Mobile Development, AWS Certificate Manager, Serverless, Cloud, Multi-factor Authentication (MFA), DevOps, Bootstrap 4, Mobile Apps, Responsive UI, Web UI, IT Consulting, JSON, Jira, RESTFul APIs, JSON Web Tokens (JWT), Learning Management Systems (LMS), Sass, AWS NLB, Elasticsearch, IT Security, Apache POI, jXLS, MariaDB, Serverless Framework, SaaS Design, TypeScript 2, AWS RDS MySQL
Full-stack Software Developer and Architect
2018 - 2018
Siemens
- Implemented the Boto 3 Cognito Identity Provider flows with Python for runtime interaction with Cognito.
- Deployed as AWS Lambda functions with serverless architecture.
- Implemented also AWS Lambda custom authentication and authorization functions with Python for AWS API GW-based web and mobile applications.
Technologies: AWS Lambda, API Gateways, Python, Amazon Cognito, Boto 3, Amazon Cognito User Pools, Full-stack, Mobile App Development, Amazon API Gateway, Amazon Route 53, Java 8, SQL, Production Support, Spring Boot, Cordova, TypeScript, Mobile, REST APIs, JSON REST APIs, HTML, Spring Data JPA, Front-end Architecture, APIs, AWS SDK, Amazon Simple Queue Service (SQS), Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, Google Cloud Platform (GCP), Amazon Simple Notification Service (SNS), Amazon RDS, SSL Certificates, Authentication, Single Sign-on (SSO), Authorization, Front-end Development, Amazon CloudWatch, HTML5, API Design, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Auth0, Auth0 API, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Database Structure, Agile Software Development, OAuth, Zuul, AWS Command Line Interface (CLI), Angular CLI, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms, Multi-factor Authentication (MFA), DevOps, Responsive UI, Web UI, IT Consulting, JSON, SMS, Jira, RESTFul APIs, JSON Web Tokens (JWT), Learning Management Systems (LMS), AWS NLB, IT Security, Apache POI, Serverless Framework, SaaS Design, TypeScript 2
Software Architect
2018 - 2018
Siemens
- Designed and built Siemens Türkiye IT's CI/CD platform as the sole engineer, implementing a Docker-based GitLab Runner on Ubuntu within a private AWS VPC subnet, connected to the corporate GitLab server exclusively through a secure VPN tunnel.
- Automated build and deployment pipelines for Siemens Türkiye IT's AWS-based applications, including Java back ends and Angular web apps, replacing manual releases with repeatable, consistent CI/CD.
- Extended the same pipelines to legacy intranet applications on Apache Tomcat, bringing automated deployments to older on-prem systems as well as new cloud workloads.
Technologies: Docker, Continuous Delivery (CD), Continuous Integration (CI), GitLab, Git, Full-stack, Mobile App Development, Amazon Route 53, Web Development, Java 8, Oracle, SQL, SSL, Jenkins, Spring Boot, Cordova, TypeScript, Mobile, REST APIs, JSON REST APIs, HTML, Spring Data JPA, Front-end Architecture, APIs, AWS SDK, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, Databases, Amazon Simple Notification Service (SNS), Amazon RDS, SSL Certificates, Authentication, Authorization, Front-end Development, Amazon CloudWatch, HTML5, API Design, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Auth0, Auth0 API, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Database Structure, Agile Software Development, OAuth, Zuul, AWS Command Line Interface (CLI), Angular CLI, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms, Responsive UI, Web UI, IT Consulting, JSON, Jira, RESTFul APIs, JSON Web Tokens (JWT), AWS NLB, IT Security, Apache POI, SaaS Design, TypeScript 2
Full-stack Software Developer and Architect
2017 - 2018
kariyerlianne.com
- Architected and built kariyerlianne.com from scratch, a job platform helping mothers with professional careers find part-time, freelance, periodic, or project-based work so they can stay in business life while caring for their children.
- Built an admin portal alongside the public site, giving the team a single place to manage the platform and its content.
- Designed and set up the AWS infrastructure from scratch, hosting the site on Amazon S3 and delivering it through Amazon CloudFront for fast, scalable, and low-cost performance.
Technologies: MySQL, GitLab CI/CD, Amazon Web Services (AWS), Node.js, Bootstrap, Angular, Full-stack, Amazon API Gateway, Amazon Route 53, Web Development, Java 8, AWS DevOps, TypeScript, Mobile, REST APIs, JSON REST APIs, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Agile, Architecture, Team Leadership, Express.js, Responsive Web Design (RWD), Databases, Amazon RDS, SSL Certificates, Authentication, Authorization, Front-end Development, Amazon CloudWatch, HTML5, API Design, Amazon CloudFront, Back-end Development, User Interface (UI), Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Database Structure, Agile Software Development, AWS Command Line Interface (CLI), Angular CLI, Angular Material, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms, Bootstrap 4, Responsive UI, Web UI, JSON, RESTFul APIs, JSON Web Tokens (JWT), TypeScript 2
AWS DevOps Architect
2017 - 2018
Siemens
- Built Siemens Türkiye IT's AWS foundation with the global Siemens cloud team: a VPN tunnel into the Siemens intranet and a VPC with three private subnets reachable only from the intranet and a public subnet with bastion, internet, and NAT gateways.
- Migrated legacy intranet web applications on Tomcat and their Oracle database into the new AWS environment, and made it the base for Siemens Türkiye IT's new mobile and web applications.
- Cut the running cost of Siemens Türkiye IT's applications to 10% of the previous level by moving them into this AWS environment.
Technologies: Amazon Virtual Private Cloud (VPC), VPN, Amazon Web Services (AWS), Full-stack, Amazon API Gateway, Amazon Route 53, AWS DevOps, REST APIs, JSON REST APIs, Spring Data JPA, Front-end Architecture, APIs, AWS SDK, Full-stack Development, CI/CD Pipelines, SaaS, Back-end, Agile, Architecture, Team Leadership, Databases, Amazon RDS, SSL Certificates, Front-end Development, API Design, Back-end Development, User Interface (UI), Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Agile Software Development, OAuth, AWS Command Line Interface (CLI), IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms, Responsive UI, Web UI, IT Consulting, JSON, RESTFul APIs, Angular Bootstrap
Full-stack Software Developer and Architect
2016 - 2018
SIEMENS AG
- Designed and developed the Siemens Pocket mobile app and its back-end services. Ported Siemens TR intranet IT web applications as mobile apps inside this single Siemens Pocket mobile application.
- Implemented the Annual Leave Request app where employees can see their remaining annual leave day balances, request a new annual leave request, and more.
- Implemented the Business Approvals App where employees can see all their pending approvals raising from the different processes within the company. This app is a dashboard for all pending approvals of any employee.
- Implemented the Lead Together mobile app for site technicians; when they are at a customer's for maintenance or service, they can negotiate with the customer and catch new maintenance, service, or project opportunities.
- Implemented the Technician Intervention mobile app. Onsite maintenance operations are logged (expanses, hours, operations, pictures, and more) via this application and signed by the customer. PDF reports are generated and delivered via mail.
- Implemented the 3i app. Employees have the possibility to suggest improvement ideas; upon measurable income, the idea owner earns money. With this process, high income has been obtained in the company.
- Implemented the Shuttle Search app. Company shuttles, their destinations, and chauffeur contact info can be looked up.
- Implemented the Meal Menu of the Day app, the most frequently used app within the company.
- Implemented the Training Evaluation app. Corporate on-site training was evaluated with this app, saving paper and digitizing employee feedback.
Technologies: MySQL, Oracle Database, Spring Boot, Angular, Ionic, Full-stack, Mobile App Development, Amazon Route 53, Java 8, Oracle, SQL, Cordova, TypeScript, REST APIs, JSON REST APIs, Spring Data JPA, APIs, Front-end Design, AWS SDK, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Agile, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, Databases, Amazon RDS, SSL Certificates, Authorization, Android, iOS, Front-end Development, Product Engineering, API Design, Amazon CloudFront, Back-end Development, User Interface (UI), Software Architecture, Order Management, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Technical Leadership, Database Structure, Agile Software Development, OAuth, Angular CLI, IntelliJ IDEA, REST, Cloud, Responsive UI, Web UI, IT Consulting, JSON, RESTFul APIs, IT Security, Angular Bootstrap
Full-stack Software Developer and Product Manager
2015 - 2018
SIEMENS AG
- Architected, designed, implemented, and managed the whole PDR process, the project execution system, and a web application for financial execution of ongoing projects of energy divisions in Siemens. More than 120 projects are managed on this system.
- Completely designed and coded the PDR product. The PDR is highly complex in terms of business logic, consisting of around 120,000 lines of Java code churn. I also developed SAP interfaces and Excel data upload-export interfaces.
- Acted as a product owner, organizing several meetings with in-company customers, defining the product roadmap, and executing the development.
Technologies: Oracle Database, Apache Tomcat, Hibernate, Spring, Vaadin, Full-stack, Java 8, Oracle, SQL, REST APIs, JSON REST APIs, Spring Data JPA, APIs, Full-stack Development, JavaScript, Back-end, Agile, Responsive Web Design (RWD), JPA, Databases, Amazon RDS, SSL Certificates, Front-end Development, Product Engineering, API Design, Back-end Development, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Database Structure, Agile Software Development, OAuth, IntelliJ IDEA, REST, Cloud, Responsive UI, Web UI, IT Consulting, JSON, RESTFul APIs, IT Security, Spring MVC, Angular Bootstrap, Document Processing
Full-stack Software Developer
2017 - 2017
Siemens
- Built Siemens Türkiye's Purchase Order Survey application for supply chain management: a web and mobile-responsive Vaadin app where categorized survey questions are prepared and sent to SCM users for evaluation.
- Integrated the survey system with SAP (via SAP JCo) and the SCM portal, so surveys are triggered automatically by SAP or portal events, or prepared manually, and delivered to users by email.
- Developed ESP, the employee search application open to all Siemens employees, with lazy-loaded, paginated results linked to Siemens' global LDAP directory for detailed employee information.
Technologies: Oracle Database, Spring Data, Spring Boot, Vaadin, Full-stack, Java 8, REST APIs, JSON REST APIs, Spring Data JPA, APIs, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Agile, JPA, Databases, Amazon RDS, SSL Certificates, Front-end Development, Product Engineering, API Design, Back-end Development, User Interface (UI), Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Database Structure, Agile Software Development, OAuth, IntelliJ IDEA, REST, Cloud, Responsive UI, Web UI, Supply Chain, IT Consulting, JSON, RESTFul APIs, IT Security, Spring MVC
Full-stack Software Developer and Architect
2017 - 2017
Siemens
- Implemented Siemens Türkiye's mobile app for its business partners, built offline-first so partners could keep working even without a network connection.
- Built the responsive admin web application with Angular and Angular Material, giving the Siemens team one place to manage the partner app.
- Used Apache CouchDB on the server and PouchDB on the device, syncing data through CouchDB's REST interfaces and real-time change notifications so the app stayed up to date automatically.
Technologies: Ionic, Angular, Google Maps, JavaScript, PouchDB, NoSQL, CouchDB, Spring Boot, REST APIs, JSON REST APIs, APIs, AWS SDK, Full-stack Development, CI/CD Pipelines, SaaS, Back-end, Architecture, JPA, Databases, Amazon RDS, SSL Certificates, iOS, Front-end Development, Product Engineering, API Design, Amazon CloudFront, Back-end Development, User Interface (UI), Solution Architecture, Content Delivery Networks (CDN), Database Structure, OAuth, Angular Material, IntelliJ IDEA, REST, Cloud, Responsive UI, Web UI, IT Consulting, JSON, RESTFul APIs, IT Security, Angular Bootstrap
Full-stack Software Developer and Architect
2016 - 2016
Siemens
- Built a VB.NET middleware service for Siemens AG Österreich's transformer factory in Weiz that keeps employee data in sync between the factory's Oracle database and SQL Server.
- Designed a staged ETL flow: the service loads all employee records from an Oracle view into a SQL Server staging table, then inserts or updates the relevant subset in the target tables.
- Made the service fully portable by bundling Oracle's managed data provider (ODP.NET) with the release, removing the need to install and maintain an Oracle client on any target server.
Technologies: Microsoft SQL Server, Oracle 12c, ODP.NET, VB.NET, Spring Boot, REST APIs, JSON REST APIs, APIs, AWS SDK, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Architecture, Databases, Amazon RDS, Front-end Development, API Design, Back-end Development, Solution Architecture, IntelliJ IDEA, REST, Web UI, IT Consulting, RESTFul APIs, IT Security, JasperReports
Full-stack Software Developer and Freelancer
2015 - 2016
Igo4Health
- Designed and developed IGO4HEALTH, a health-tourism platform that packages medical services for international patients, and sold the product to an international customer.
- Built the full product suite: a public website, an admin portal for running the platform, and a hospital access panel for partner hospitals.
- Developed the Ionic mobile app for iOS and Android and published it on both the App Store and Google Play, giving patients mobile access to health-tourism packages.
Technologies: MySQL, NGINX, Ionic, AngularJS, Node.js, REST APIs, JSON REST APIs, APIs, Full-stack Development, JavaScript, SaaS, Back-end, Architecture, Databases, Amazon RDS, Front-end Development, API Design, Amazon CloudFront, Back-end Development, User Interface (UI), Angular Material, IntelliJ IDEA, REST, Mobile Development, Web UI, RESTFul APIs
Full-stack Software Developer and Product Manager
2014 - 2016
Siemens
- Implemented ITA-MOR, Siemens AG's web application for managing IT assets such as PCs and smart mobile devices, used across Siemens regions in Austria, Russia, and Türkiye.
- Managed development of Milion, the web application that brought Siemens Türkiye's business strategy process online: defined development guidelines, reviewed delivered code and documents, and enforced quality standards.
- Took product ownership of several Java web applications handed over to Siemens IT, delivering multiple change-request packages and supporting their business users.
Technologies: Oracle Database, MySQL, Apache Tomcat, Spring, Hibernate, Bootstrap, PrimeFaces, JSF, REST APIs, JSON REST APIs, APIs, Full-stack Development, JavaScript, Back-end, JPA, Databases, Apache Struts 2, Front-end Development, Jira REST API, Back-end Development, User Interface (UI), OAuth, IntelliJ IDEA, REST, Web UI, Inventory Management, IT Consulting, JasperReports, Apache Struts, Reports
Senior Software Developer
2013 - 2014
Nortel Networks - Netaş
- Analyzed the project's core modules, designed the database with PowerDesigner, and produced UI mockups used in negotiations with the customer.
- Built proofs of concept for the most complex modules, including an organization-wide chat that integrated an XMPP chat server with WebLogic, with web push delivery and its own chat database design.
- Developed POCs for database audit logging with Spring AOP, a mailbox module (database and API design), and caching with Spring and EhCache, de-risking the architecture before full development.
Technologies: XMPP, Oracle Database, WebLogic, PrimeFaces, OmniFaces, JSF, Spring, Apache Maven, Spring Boot, JSON REST APIs, APIs, Full-stack Development, Back-end, JPA, Databases, Front-end Development, Back-end Development, User Interface (UI), Eclipse IDE, Web UI
Full-stack Software Developer & Architect
2012 - 2013
Nortel Networks - Netaş
- Built KKTC E-Nüfus, the national population registration system of the Turkish Republic of Northern Cyprus, which digitalized all of the country's population registries.
- Covered the full civil registry: births, deaths, marriages, divorces, adoptions, legitimations, and recognitions, plus immigration, emigration, and changes of residence.
- Started the project as its first senior developer and architect, and guided it as the team grew to two testers and three more developers, taking the system from design to nationwide use.
Technologies: JAX-WS, Web Services, jQuery, PrimeFaces, JSF, Spring JDBC, Apache Maven, PostgreSQL, Spring Boot, APIs, Full-stack Development, Back-end, Databases, NetBeans, Front-end Development, Highcharts, Enterprise Java Beans (EJB), Back-end Development, User Interface (UI), Eclipse IDE, Web UI, Chart.js
Senior Software Developer
2010 - 2012
Nortel Networks - Netaş
- Built a Java Swing desktop client (JNLP) for Turkcell's Ayna project with management, monitoring, filtering, reporting, and lazy-loaded paginated data views, plus an auto-refreshing live dashboard built with JFreeChart.
- Developed a GSM service manager for Turkcell that defines IP-based services and their delivery protocols in an XML-based service definition language (ESDL) with a shared XSD template, with a jQuery UI front end.
- Built the system management interface of Türksat's E-Devlet (Turkish e-government) Secure XML Gateway with JSF 2.0 and PrimeFaces.
- Designed and built proofs of concept with jQuery and JSP/Servlets for Turkcell, Türksat, and Turkish Airlines projects in Netaş's national R&D program.
Technologies: Balsamiq, Wireframing, XML, Servlet, Jakarta Server Pages (JSP), CSS3, User Interface (UI), jQuery, JFreeChart, Java Natural Language Processing (JNLP), Swing, Spring Boot, Full-stack Development, Databases, NetBeans, Front-end Development, Highcharts, Eclipse IDE, Web UI, Chart.js
Senior Software Developer
2010 - 2012
Nortel Networks - Netaş
- Developed the UI and services of Turkcell's end-to-end monitoring platform, a deep packet inspection system for monitoring and managing GSM service data, as part of a three-person team.
- Turned raw GSM network data into insight end to end, from network-level data analysis through the services layer to the web application used to monitor Turkcell's services.
- Built dashboards, alerts, and anomaly detection on GSM service data, helping Turkcell spot service problems early instead of reacting after customers noticed them.
Technologies: Oracle Database, Jakarta EE (Java EE or J2EE), WebLogic, PrimeFaces, JSF, Spring Boot, Full-stack Development, Databases, TCP/IP, NetBeans, Front-end Development, Highcharts, Enterprise Java Beans (EJB), Eclipse IDE, Web UI
Senior Software Design and Development Engineer
2008 - 2010
Nortel Networks - Netaş
- Worked intensively on Nortel Networks' ATCA program, migrating the next-generation VoIP call server (gateway controller), a system of about 8 million lines of mainly C/C++ code, to new hardware and a new operating system.
- Moved the platform from Motorola big-endian processors to Intel little-endian hardware, adapting byte-order-sensitive C/C++ code across the codebase so the call server behaved identically on the new architecture.
- Ported the call server from a real-time operating system (RTOS) to Nortel's Linux, as part of changing both hardware and operating system in the same migration.
Technologies: VoIP, Linux, C++, C, Full-stack Development, TCP/IP, Red Hat Linux
Researcher and Software Developer
2007 - 2008
Liris-CNRS, Lyon France
- Conducted computer vision research at the LIRIS lab (CNRS) at INSA de Lyon, developing object description and detection algorithms based on local image features such as SIFT and SURF.
- Extended the detection work with global image features such as Gabor filters, broadening the set of descriptors available for object recognition.
- Built real-time video analysis and object tracking algorithms that tracked vehicles and detected license plates in live video.
- Implemented distance estimation from a single monocular camera, and calibrated multi-camera setups for multi-view vision.
Technologies: Tracking, Object Detection, Sift Science, Image Processing
Experience
IEEE Conference
R. Yildiz, T. Acarman, Image Feature Based Video Object Description and Tracking, IEEE International Conference on Vehicular Electronics and Safety, July 24-27 2012, Istanbul Turkey
Book Chapter
Feature-Based Robust Description and Monocular Detection: An Application to Vehicle tracking.
HYBRID INTELLIGENCE FOR IMAGE ANALYSIS AND UNDERSTANDING.
.
Ramazan Yıldız, Tankut Acarman, Pages: 187–203, 2017 Published Online: 14 AUG 2017, DOI: 10.1002/9781119242963.ch8
HYBRID INTELLIGENCE FOR IMAGE ANALYSIS AND UNDERSTANDING.
.
Ramazan Yıldız, Tankut Acarman, Pages: 187–203, 2017 Published Online: 14 AUG 2017, DOI: 10.1002/9781119242963.ch8
Veraxon: Multi-tenant Permit-to-work SaaS for High-risk Industrial Work
https://veraxon.ioAs fractional CTO and founding engineer for New Age Safety Solutions, a UK health-and-safety consultancy, I took Veraxon from an empty repository to production in under four months as the company's only engineer. Veraxon replaces paper permits for high-risk site work such as hot works, confined spaces, electrical work, and work at height, and is built around UK HSE permit-to-work guidance: separation of duties, controlled issue and acceptance, pre-work briefings, and a 10-year audit trail.
I gathered requirements with the company's owner, an HSE expert, researched the regulations, and designed the product and its architecture. I then built the whole platform myself: a multi-tenant NestJS and PostgreSQL back end with strictly isolated data per client company, a React PWA for iOS, Android, and desktop, a Python service that produces legally defensible permit PDFs, and QR verification for on-site inspectors.
The AWS infrastructure is fully in Terraform, running on ECS Fargate behind API Gateway and WAF, with keyless GitHub Actions deployments and 600+ end-to-end tests. I also produced the product videos and built the company's corporate website, nassltd.com.
I gathered requirements with the company's owner, an HSE expert, researched the regulations, and designed the product and its architecture. I then built the whole platform myself: a multi-tenant NestJS and PostgreSQL back end with strictly isolated data per client company, a React PWA for iOS, Android, and desktop, a Python service that produces legally defensible permit PDFs, and QR verification for on-site inspectors.
The AWS infrastructure is fully in Terraform, running on ECS Fargate behind API Gateway and WAF, with keyless GitHub Actions deployments and 600+ end-to-end tests. I also produced the product videos and built the company's corporate website, nassltd.com.
HD-Map Data Platform for Autonomous Driving (Woven by Toyota)
At Woven by Toyota, I lead the HD-map data platform of an autonomous-driving map team. The platform ingests NDS.Live HD-map releases from Tier-1 map suppliers into a lane-level PostGIS database on AWS Aurora, derives about 100 analytical and visualization layers, and publishes them through GeoServer and GeoNode for route validation and map QA.
I joined as a backend and platform architect for the map-delivery pipeline and became the lead engineer of the whole platform. I authored the scaling roadmap that took the database from North America to Japan-size releases of 2.6 billion rows, using sharding, partitioning, and query-planner fixes that cut the heaviest refresh from 2+ hours to about 5 minutes, with every phase shipped as a revertible, measured release.
I also rebuilt the ingestion pipeline into a self-service control plane (FastAPI, React, Kubernetes Jobs, Entra ID, Vault), ran the production Aurora cluster with Terraform, and resolved critical incidents on the autonomous-driving path, including a same-night fix that cut memory demand from 1,536 GB to 96 GB.
I joined as a backend and platform architect for the map-delivery pipeline and became the lead engineer of the whole platform. I authored the scaling roadmap that took the database from North America to Japan-size releases of 2.6 billion rows, using sharding, partitioning, and query-planner fixes that cut the heaviest refresh from 2+ hours to about 5 minutes, with every phase shipped as a revertible, measured release.
I also rebuilt the ingestion pipeline into a self-service control plane (FastAPI, React, Kubernetes Jobs, Entra ID, Vault), ran the production Aurora cluster with Terraform, and resolved critical incidents on the autonomous-driving path, including a same-night fix that cut memory demand from 1,536 GB to 96 GB.
Siemens Product Info Cockpit (PIC): Product Data Platform for 3.7 Million Products
Product Info Cockpit (PIC) gives Siemens product managers one place to search 3.7 million products with their technical and commercial data, pictures, documents, and product relations. As a hands-on senior architect in a team of 10, I delivered the greenfield MVP on schedule in three months, and the delivery earned approval of a EUR 270k follow-on budget.
I owned the technical shape end to end and did most of the hands-on work across infrastructure, back end, front end, and quality. I built a Node.js/TypeScript back end that turns six Kafka product-data streams from SAP and product-master systems into a 3.7 million-document MongoDB index, kept current by resumable backfill and hourly syncs, plus a bilingual React app on the Siemens iX design system.
On AWS, I built the Terraform landing zone across dev, QA, and production (EKS on Fargate, WAF, Secrets Manager), Microsoft Entra ID sign-in at the load balancer with role- and business-unit-based access, and a GitLab CI/CD pipeline with no static credentials. In-cluster Playwright and k6 tests showed about 6x capacity headroom at the expected load.
I owned the technical shape end to end and did most of the hands-on work across infrastructure, back end, front end, and quality. I built a Node.js/TypeScript back end that turns six Kafka product-data streams from SAP and product-master systems into a 3.7 million-document MongoDB index, kept current by resumable backfill and hourly syncs, plus a bilingual React app on the Siemens iX design system.
On AWS, I built the Terraform landing zone across dev, QA, and production (EKS on Fargate, WAF, Secrets Manager), Microsoft Entra ID sign-in at the load balancer with role- and business-unit-based access, and a GitLab CI/CD pipeline with no static credentials. In-cluster Playwright and k6 tests showed about 6x capacity headroom at the expected load.
Education
2011 - 2013
Master of Science Degree in Computer Vision, Image, and Real-time Video Image Processing
Galatasaray University - Istanbul, Turkey
2007 - 2008
Master of Science Degree in Computer Vision and Image Processing
INSA of Lyon (National Institute of Applied Sciences of Lyon) - Lyon, France
2003 - 2007
Bachelor of Science Degree in Computer Engineering
Galatasaray University - Istanbul, Turkey
Skills
Libraries/APIs
Node.js, React, REST APIs, Google Maps API, Auth0 API, OpenAI API, AG Grid, NgRx, Apache POI, Puppeteer, RxJS, jQuery, Restify, Highcharts, Chart.js, Jira REST API, Pandas, JasperReports, jXLS, Twilio API, GSON, Snap.svg, Google Maps, JAX-WS, Java Natural Language Processing (JNLP), JFreeChart, PrimeNG, Socket.IO, NgRx/store, Telegram Messenger API, Jenkins Pipeline, Java Message Service (JMS), Auth0 Management API v2, Terragrunt, SQLAlchemy, OpenAPI, Playwright, Zod, React Hook Form, FFmpeg, Stripe
Tools
Apache Maven, GitLab, Angular CLI, Amazon Virtual Private Cloud (VPC), Amazon Cognito, Amazon CloudFront CDN, AWS Command Line Interface (CLI), IntelliJ IDEA, Amazon Simple Notification Service (SNS), GitHub, Amazon CloudWatch, Amazon CloudFront, Capacitor, Auth0, Jira, ChatGPT, AWS IAM, AWS SDK, Amazon Elastic Block Store (EBS), Git, GitLab CI/CD, Amazon Simple Queue Service (SQS), Eclipse IDE, Apple Push Notifications, Amazon Simple Email Service (SES), Apache Tomcat, Zuul, ActiveMQ, Amazon EKS, Figma, Amazon Elastic Container Service (ECS), MongoDB Atlas, VPN, NGINX, Boto 3, Servlet, Balsamiq, Sift Science, Sequelize, Jenkins, AWS Transfer Family, Knex.js, Docker Compose, Terraform, Grafana, Microsoft Intune, Bitbucket, Amazon Elastic Container Registry (ECR), Azure Kubernetes Service (AKS), AWS Step Functions, Sentry, AWS Cloud Development Kit (CDK), Keycloak, AWS Fargate, Docker Swarm, Kubectl, Helm, Istio, HashiCorp Vault, AWS PrivateLink, Bazel, RabbitMQ, Pytest, Kustomize, Grafana k6, AWS Systems Manager, Vitest, Prisma, WeasyPrint, Astro, Microsoft Power BI
Languages
Python, Java 8, TypeScript 3, JavaScript, HTML5, Java, TypeScript, SQL, CSS, HTML, SCSS, Sass, TypeScript 2, VB.NET, CSS3, XML, C, C++, Python 3, GraphQL, Java 11, Java 21, Go, Bash, Snowflake
Frameworks
Ionic, Bootstrap, Angular, Angular Material, Vaadin, Spring Boot, NestJS, Tailwind CSS, Express.js, JPA, JavaScript MVC, OAuth 2, JSON Web Tokens (JWT), Jasmine, Spring MVC, Ionic 3, Spring, Jest, Spring Microservice, Django, Apache Struts, Serverless Framework, Swagger, Hibernate, Spring JDBC, Swing, Jakarta Server Pages (JSP), AngularJS, JSF, PrimeFaces, Cypress, Next.js, Apache Struts 2, Thymeleaf, i18next
Paradigms
Continuous Integration (CI), Mobile Development, REST, Agile, Scrum, Responsive Web Design (RWD), Agile Software Development, Back-end Architecture, DevOps, Asynchronous Programming, Functional Programming, Test-driven Development (TDD), Microservices, Microservices Architecture, Continuous Delivery (CD), Functional Reactive Programming, ETL, Serverless Architecture, DevSecOps, User Acceptance Testing (UAT), Offline-first Development, Role-based Access Control (RBAC), Load Testing, E2E Testing, Requirements Analysis, Event-driven Architecture, Automation
Platforms
Amazon Web Services (AWS), AWS Lambda, Amazon EC2, Docker, Oracle, Mobile, Amazon, Android, iOS, AWS ALB, AWS NLB, Red Hat Linux, Linux, Twilio, Google Cloud Platform (GCP), Kubernetes, NetBeans, Oracle Database, Jakarta EE (Java EE or J2EE), Firebase, Azure, AWS IoT, Apache Kafka, Confluent Cloud, Windows Server
Storage
MySQL, Spring Data, Spring Data JPA, PostgreSQL, Redis, SQLite, Databases, Database Structure, JSON, IndexedDB, Amazon S3 (AWS S3), CouchDB, Amazon DynamoDB, PouchDB, MongoDB, Amazon Aurora, Redis Cache, MariaDB, Microsoft SQL Server, NoSQL, Oracle 12c, Firebase Realtime Database, Spring Data MongoDB, Datadog, PostGIS, Amazon EFS, Elasticsearch, GeoServer, Azure Active Directory, Microsoft Entra ID, Database Migration, Data Validation, Database Administration (DBA), Data Integration
Other
API Gateways, RESTful Services, Web Services, User Interface (UI), Amazon Cognito User Pools, Amazon API Gateway, AWS Certificate Manager, Web Development, Mobile App Development, AWS DevOps, Full-stack, Production Support, Cordova, Front-end, JSON REST APIs, Progressive Web Applications (PWAs), Helidon, Software Development, Engineering, Computer Science, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, SaaS, API Integration, Back-end, Architecture, Team Leadership, PWA, Amazon RDS, SSL Certificates, Vite, Authentication, Authorization, Front-end Development, CSV File Processing, CSV, Data Visualization, WebSockets, Product Engineering, API Design, Back-end Development, System Architecture, Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Technical Leadership, OAuth, Cloud, Cloud Platforms, Integration, Multi-factor Authentication (MFA), FastAPI, AWS Secrets Manager, Bootstrap 4, Mobile Apps, Responsive UI, Web UI, IT Consulting, RESTFul APIs, ECS, Autoscaling, Data Extraction, Data Structures, Document Processing, AWS Cloud Architecture, Leadership, IT Security, PDF, Reports, PWA or Progressive Web Apps, Mobile First, Advisory, SaaS Design, Tracking, Web Scraping, Angular Bootstrap, SSL, Algorithms, Videos, Data Scraping, Infrastructure as Code (IaC), SDKs, User Experience (UX), TCP/IP, Single Sign-on (SSO), Scraping, Video Streaming, Order Management, Serverless, OpenAI, Finance APIs, SMS, Data Engineering, Learning Management Systems (LMS), Artificial Intelligence (AI), CTO, AI Virtual Assistant, Large Language Models (LLMs), AI Agents, AI Integration, Finance, Prompt Engineering, Retrieval-augmented Generation (RAG), AI Chatbots, Audio Processing, Digital Signal Processing, Amazon Route 53, Load Balancers, SAP, Telnet Protocol, ODP.NET, VoIP, Wireframing, OmniFaces, XMPP, Image Processing, Object Detection, DocumentDB, WebLogic, Gatsby, Apollo, Material Design, SFTP, AWS VPN, Virtual Threads, Ionic 7, NATS, GitHub Actions, Prometheus, Vulnerability Assessment, Web App Development, Workday, QuickFIX, Natural Language Processing (NLP), Human-machine Interface (HMI), Software Engineering, Performance Analysis, Robotics, Image Synthesis, Advanced Modelization, Geometry, Image Analysis, Multimedia Compression, Mathematics, Information Retrieval, Computer Networking, Video Processing, Microsoft Entra, Enterprise Java Beans (EJB), OBJ Format, Geospatial Data, Offline Data Synchronization, Logistics, Supply Chain, Inventory Management, M2M, Security, Geodatabases, Offline Maps, Serial Communication, Payment APIs, AWS WAF, AWS RDS MySQL, GeoNode, OGC (WMS/WFS), HD Maps, Geospatial Data Pipelines, Dagster, Platform Engineering, LakeFS, Cobra, Click, GeoFence, SLD, NDS.live, External Secrets, OAuth 2.0 / OIDC, JFrog Artifactory, OpenTelemetry, Testcontainers, Materialized View, Query Optimization, OpenID Connect (OIDC), Database Sharding, Database Partitioning, Incident Response, NDS.Live, Advanced Driver-assistance Systems (ADAS), Microsoft Graph API, Wiz Cloud Security Platform, SAP Integration, Accessibility Testing, Java 25, Spring Boot 4, Ionic 8, Multitenancy, Legacy Application Modernization, Product Ownership, Workflow Design, IT Product Management, Product Marketing, Postmark, GDPR, Product Management, TanStack Query, Video Production, Stakeholder Management, Regulatory Compliance, AWS Auto Scaling, Blue-green Deployment, Zero-downtime Deployment, Site Reliability Engineering (SRE), AWS Systems Manager (SSM), Amazon EventBridge, AWS Certificate Manager (ACM), Docker Registry, Monitoring, Monitoring & Alerting, Disaster Recovery (DR), Cloud Migration, Network File System (NFS), Hybrid Cloud Infrastructure, Cloud Infrastructure, Storage, File Systems, Networking, Migration Planning, Cutover Planning, Boto3, Cost Reduction & Optimization (Cost-down), Technical Training, Data Migration, Database Schema Design, Backup & Recovery, Database Monitoring, Legacy System Modernization, IT, Digital Watermarking, Webhooks, Network Security, Power BI, Hybrid Mobile Apps, Payment Terminals, Point of Sale, Progressive Web Apps (PWA), GeoPandas, Microsoft Entra ID (Azure AD)
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