Shun Inagaki
Full-Stack Developer
London, UK
Accomplished Full-Stack Developer with proven expertise in building scalable web applications. Experienced in leading teams and delivering high-performance systems across international projects.
About Me
I am Shun Inagaki and have been working as a Full-Stack Developer at SCSK Europe Ltd., based in London, UK, with around 5 years of experience in full-stack web application development and 1.5 years in database engineering.
Passionate about building scalable, high-performance systems, I strive to bridge the gap between technology and business problems. Throughout my career, I have successfully managed teams of 4–5 engineers, ensuring the efficient balance of cost, timelines, and product quality while fostering a collaborative and goal-oriented culture.
Career History
Full Stack Developer
SCSK Europe Ltd.
Jun 2025 – Present
London, United Kingdom (Hybrid)
- Led development projects of Treasury Management System, including specification design, development, testing, and direct client communication
- Coordinated development projects and operational tasks utilizing Jira, managing development initiatives, customer support requests, and system outages
- Conducted product demonstrations for prospective clients, clearly articulating product functionality to drive engagement
- Provided support to existing customers, resolving technical inquiries and improving satisfaction through responsive engagement
Full Stack Developer / Team Lead
Leverages Co., Ltd.
Mar 2021 – May 2025
Full Stack Developer / Team Lead (Oct 2022 – May 2025)
Tokyo, Japan (On-site)
- Led end-to-end web application development, overseeing architecture, implementation, and operation across infrastructure and application layers
- Designed and implemented sitemap generation features within scheduled job tasks on a Laravel application, resulting in a 10% increase in organic search sessions
- Managed a team of five engineers, effectively balancing cost, delivery time, and product quality to align with strategic product goals
- Collaborated with marketing, sales, and product management teams to prioritize development, ensuring alignment between business objectives and technical strategy
- Awarded top 3 ranking out of 120+ engineers in the company's bi-annual performance awards (April 2023)
Full Stack Web Developer (Mar 2021 – Sep 2022)
Tokyo, Japan (Hybrid)
- Handled full-stack development, including backend development of REST APIs using Laravel and frontend development with React
- Designed and optimized AWS architecture, implementing GitHub Actions for CI/CD automation
- Proposed and developed an auto account generation feature for company-side admin pages in recruitment media platform, significantly improving operational efficiency and streamlining the activation workflow
Database Engineer
Lincs Inc.
Jun 2019 – Feb 2021
Tokyo, Japan (On-site)
- Developed batch processing programs using PL/SQL
- Optimized over 1,000 SQL queries, improving query performance
- Conducted GoldenGate performance testing, comparing Oracle 11g and 19c, and delivered comprehensive analytical reports
- Supported Oracle 11g to 19c database migration for approximately 5 terabytes by developing migration scripts
- Pioneered SQL execution plan performance testing methodologies, successfully identifying key differences between Oracle 11g and 19c
- Configured Linux virtual servers with Oracle DB using VMware Player for development and testing environments
- Completed external technical training courses covering Java, SQL, Oracle DB, Linux, and HTML/CSS
- Obtained certifications including Java SE8 Programmer II and Oracle Master 12c Bronze
Intern / Consultant Trainee
SOLIZE Holdings Corporation
Jan 2019 – May 2019
Tokyo, Japan (On-site)
Consultant Trainee (Apr 2019 – May 2019)
- Completed new employee training programs including presentation skills, business communication, and business knowledge training
Intern (Jan 2019 – Mar 2019)
- Performed data cleansing for machine learning projects
- Conducted annotation work for machine learning datasets
- Created recruitment management spreadsheets in Excel
Education
MSc Computer Science
University of York
2020 – 2022 • Merit
York, United Kingdom
MSc International Business
University of Leeds
2017 – 2018 • Merit
Leeds, United Kingdom
BA Human Development
Kobe University
2013 – 2017 • GPA: 3.45
Kobe, Japan
Technical Skills
Programming Languages
PHP
TypeScript
C#
Python
JavaScript
Frameworks
Laravel
React
Next.js
.NET
Node.js
Cloud & DevOps
AWS
CDK
Docker
Terraform
GitHub Actions
ElasticStack
CloudWatch
CI/CD
Databases
MySQL
Oracle
SQL Server
Redis
Elasticsearch
Operating Systems
Linux (Ubuntu)
Windows
Tools & Version Control
Git
GitHub
Jira
Confluence
Slack
Frontend Technologies
HTML
CSS
Tailwind CSS
Responsive Design
Languages
Japanese (Native)
English (Professional Proficiency)
Projects
Key Technologies:
Key Responsibilities:
ISO 20022 Payment Export Migration
Treasury Management System - Operation, Management & Development
Recruitment Service Launch - MVP Site Development
Owned Media Platform Consolidation
Infrastructure Reliability Enhancement
User Experience & Operational Efficiency Enhancement
Engineering Team Leadership & Development
Performance Optimization & Cost Efficiency
Sales Operations Transformation & KPI Visualization
Incident Management & System Reliability
Organizational Goal Alignment & Communication
Job Posting Auto-Translation System Development
Article Translation Management System Development
OKR Achievement & Data-Driven Goal Management
Article Media Platform Renewal & Project Management
Job Board Management System - Business Model Transformation & Freemium Platform Development
Data Archiving & Cost Optimization System
SEO Optimization & Search Visibility Enhancement
Oracle Database Migration (11g to 19c)
AWS Infrastructure Automation with CDK
Job Board Platform Replatforming & Architecture Modernization
SCSK Europe Ltd.
SCSK Europe Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Leverages Co., Ltd.
Lincs Inc.
Leverages Co., Ltd.
Leverages Co., Ltd.
Led the migration of payment instruction export functionality from legacy MT103 format to ISO 20022 pain.001.001.09 standard in a treasury management system. Designed and implemented XML generation logic, validation mechanisms, and format conversion processes to ensure compliance with international banking standards.
Leading comprehensive development and operational management of an in-house treasury management system. Driving end-to-end project delivery from specification design through deployment, while managing customer support requests and system incidents. Actively engaging with clients through product demonstrations and technical support to enhance satisfaction and drive business growth.
Served as technical lead and project manager for the development of a new recruitment service platform. Conducted comprehensive analysis of market trends, competitor systems, and technical requirements to select optimal technology stack. Successfully delivered high-quality MVP with exceptional conversion rate in rapid timeframe while maintaining cost efficiency.
Served as implementation lead and technical advisor for consolidating multiple regional owned media sites into a unified platform for the international business. Conducted thorough analysis of existing systems, requirements, and team capabilities to recommend cost-efficient technology stack that balances performance, maintainability, and development velocity.
Led comprehensive infrastructure modernization initiative to improve system reliability, fault tolerance, and operational efficiency. Implemented strategic improvements across infrastructure, database, and application layers, including containerization, auto-scaling optimization, and database segmentation to ensure high availability and performance.
Led data-driven UX improvement initiatives for recruitment agent platform, utilizing analytics tools to identify user behavior patterns and operational bottlenecks. Conducted field observations and stakeholder interviews to understand CA workflows, implementing improvements that enhanced both user satisfaction and business efficiency while managing cross-functional collaboration.
Successfully managed and developed a team of 4-5 engineers across multiple concurrent projects, fostering a culture of autonomy, ownership, and continuous growth. Established comprehensive development framework including monthly issue-sharing sessions, personalized task assignments aligned with individual career goals, and structured feedback mechanisms. Created transparent KPI monitoring systems and implemented process improvements that significantly enhanced team capabilities, business impact awareness, and cross-functional collaboration.
Led comprehensive performance optimization initiatives across multiple systems, combining technical expertise with analytical problem-solving to identify and resolve bottlenecks. Implemented cost-efficient solutions including WordPress caching optimization, database query improvements, and infrastructure architecture decisions that balanced performance requirements with budget constraints.
Led cross-functional initiative to transform sales productivity and data visibility for recruitment business division. Conducted comprehensive business process analysis and stakeholder interviews to identify operational bottlenecks. Designed and implemented CRM workflow improvements and comprehensive KPI monitoring systems covering both candidate-facing and client-facing operations, enabling data-driven decision making and strategic planning across sales, marketing, and product teams.
Established systematic incident management framework and proactive system reliability improvements. Implemented structured incident response protocols with clear communication timelines and business impact quantification. Conducted systematic analysis of recurring alerts to prioritize resolution based on frequency, business impact, and cost-benefit analysis, reducing operational overhead and improving system stability across multiple services.
Established comprehensive goal communication and alignment framework to connect team activities with business objectives. Transformed quarterly planning process from one-way announcements to interactive sessions with transparent business context sharing. Implemented multi-layered communication approach including project kickoffs with QCDS prioritization, bi-weekly progress updates, and impact visualization systems that significantly improved team's business awareness and autonomous decision-making capabilities.
Designed and implemented automated translation system for job postings using AWS Translate API to streamline multilingual content creation for international recruitment platform. Developed comprehensive translation workflow including API integration, translation quality management, and content synchronization mechanisms. Created technical infrastructure that balanced translation accuracy with operational efficiency while reducing manual translation overhead.
Led development of Laravel Admin-based translation management system to enhance content writer productivity for media article translation workflow. Completed full development cycle from requirements gathering to production release within two weeks. Established systematic translation workflow and quality control processes that received positive feedback from content writers and significantly improved operational efficiency across international media platform.
Consistently achieved quarterly OKRs through systematic goal management, data-driven decision making, and proactive progress tracking. Established transparent KPI monitoring systems and progress visualization mechanisms that enabled early issue identification and adaptive strategy adjustments. Fostered team-wide OKR understanding and autonomous contribution culture, resulting in consistent goal achievement and business impact delivery across multiple quarters.
Led comprehensive media platform renewal project as Project Manager and technical lead, orchestrating full-stack development, stakeholder coordination, and schedule management. Conducted strategic technology selection including Tailwind CSS adoption for improved maintainability, implemented user-centric CMS functionality through stakeholder interviews, and proactively addressed SEO requirements beyond initial specifications. Successfully delivered on-schedule release despite multiple production incidents by implementing flexible resource allocation, critical path management, and protecting team focus time from interruptions.
Led transformative business model shift from traditional recruitment platform to freemium SaaS model, orchestrating comprehensive product development, authorization architecture redesign, and agile methodology transition. Managed complex stakeholder coordination across engineering, Salesforce, and sales teams while implementing systematic QCDS controls and critical path management. Established proactive KPI monitoring system that identified advertising cost optimization opportunities, and architected scalable authorization middleware preventing configuration errors during rapid feature expansion. Successfully delivered initial release on schedule while achieving above-target conversion rates that accelerated paid feature prioritization.
Designed and implemented automated old job deletion and archiving system for job board platform, addressing database bloat and query performance degradation. Architected cost-optimized data archiving solution leveraging Apache Hive partitioning format for efficient AWS Athena queries, implemented stream-based CSV writing to prevent memory overflow, and established S3 storage strategy balancing accessibility with cost efficiency. Successfully reduced operational database size while maintaining historical data availability for analytics.
Led technical SEO implementation for job board platform in collaboration with marketing team, expanding beyond traditional engineering scope to drive organic growth. Conducted systematic analysis of Search Console data, sitemap configuration, and indexing issues to identify optimization opportunities. Designed and implemented technical SEO solutions including structured data markup for Google Jobs integration, sitemap architecture improvements, and index management that significantly improved search visibility and session metrics.
Supported Oracle database migration project from version 11g to 19c for approximately 5 terabytes of data. The project included developing migration scripts, performance testing, SQL query optimization, and validation.
Contributed to AWS infrastructure deployment pipeline development using AWS CDK and GitHub Actions as partial implementation lead. The solution enabled environment provisioning, consistent configurations, and deployment automation for microservices.
Contributed to comprehensive platform replatforming project for job board, implementing technology stack upgrades, architectural improvements, and infrastructure migration while maintaining service continuity. Proposed strategic process improvements to enhance development velocity, standardized Presenter layer implementation for clean architecture separation, and executed critical technology migrations including ElasticStack version upgrade and containerization of RPA workflows. Established proactive quality assurance practices with daily error log monitoring and comprehensive testing protocols post-launch.
Migrated payment export format from MT103 to pain.001.001.09 (ISO 20022)
Developed XML generation and validation logic for payment instructions
Implemented data mapping and transformation from legacy format to ISO 20022
Led development projects including specification design, development, testing, and direct client communication
Coordinated development projects and operational tasks using Jira, managing development initiatives, customer support requests and system outages
Conducted product demonstrations for prospective clients, clearly articulating product functionality to drive engagement
Provided support to existing customers, resolving technical inquiries and proactively improving satisfaction through responsive engagement
Selected and implemented Laravel + Inertia.js (React) + MySQL stack based on multi-faceted evaluation of system architecture, security, scalability, team capabilities, and infrastructure costs
Completed full-stack development in 2.3 person-months over 1.2 months, enabling rapid market entry
Achieved approximately 20% conversion rate, demonstrating high product quality and user experience
Proposed Remix + SQLite (EFS) + Drizzle ORM architecture considering system requirements, team skills, and infrastructure resource costs
Optimized infrastructure costs while maintaining high performance and scalability
Designed architecture for easy maintenance and future portability across different environments
Migrated services from EC2 to ECS with optimized Auto Scaling configuration, improving fault tolerance and reducing maintenance overhead
Implemented RDS database segmentation and eliminated shared resources across environments to enhance system isolation and reliability
Established security update monitoring and response workflows, ensuring timely vulnerability remediation
Analyzed user behavior using Clarity and Google Analytics, identifying and resolving critical UX issues that impacted conversion rates
Conducted business process analysis and stakeholder interviews, proposing CRM and portal improvements that increased operational efficiency
Implemented auto account generation feature for administrative interface, significantly streamlining the activation workflow
Transformed goal-setting process by introducing monthly issue-sharing sessions to improve OKR understanding and self-determination, resulting in increased team commitment and business-aligned individual objectives
Implemented productivity-enhancing initiatives including ide-helper setup across repositories, staging environment workflow optimization, and systematic alert threshold reviews to eliminate operational bottlenecks
Delegated critical responsibilities (PM duties, sprint management, production deployments) with intentional growth opportunities and constructive feedback cycles, improving team autonomy and analytical capabilities
Identified and resolved WordPress API caching issues causing 5+ second delays, reducing intermittent latency to cache-refresh-only occurrences through systematic analysis and plugin implementation
Optimized database performance through SQL query tuning, algorithm improvements, and MySQL fragmentation resolution across end-to-end system layers
Designed cost-efficient architecture using SQLite on EFS instead of RDS, ARM architecture over Intel, and RDS auto-optimization features, creating infrastructure cost management tracking system
Conducted business process analysis to understand recruitment workflows, created process flow diagrams mapping system objects to operational steps, and drove implementation of productivity improvements including automated workflows and UI enhancements
Designed and built comprehensive KPI monitoring systems with multi-dimensional analysis tracking all recruitment funnel metrics and lead times, enabling performance reviews, strategic planning, and marketing optimization
Created KPI visualization system tracking multiple acquisition channels with complete funnel metrics, supporting daily operations and strategic decision-making
Developed incident response framework including initial reporting, impact assessment with revenue calculations, temporary mitigation, stakeholder communication, and permanent resolution to maximize stakeholder trust
Systematically analyzed alert patterns across services, implementing retry mechanisms for transient ECS network errors, adjusting alert severity for low-priority services, and optimizing notification triggers to reduce false positives
Proactively identified and resolved chronic system alerts before Q4 major project launches, eliminating production disruptions and improving development velocity through reduced context switching
Redesigned quarterly planning from announcement-based to dialogue-based format, introducing issue-sharing sessions that improved OKR understanding and enabled team members to propose business-aligned initiatives beyond product development
Implemented systematic impact visualization including cost reduction dashboards, conversion tracking spreadsheets, and security improvement metrics, enabling team members to understand business impact of their work
Established project kickoff protocols with clear QCDS prioritization and continuous reinforcement through daily communication, resulting in team members autonomously proposing implementation changes aligned with project priorities
Integrated AWS Translate API into job posting workflow, implementing automated translation pipeline with quality validation and review processes
Designed translation accuracy improvement mechanisms including terminology consistency enforcement and context-aware translation optimization
Developed bilingual content synchronization system ensuring translation updates propagate correctly across multiple language versions
Developed Laravel Admin-based translation management system within two-week timeline, completing requirements definition, design, implementation, and production release
Implemented workflow automation and quality assurance features that significantly enhanced content writer productivity, receiving appreciation from translation team for operational improvements
Established systematic review processes and validation checkpoints to maintain high translation standards while accelerating content delivery timelines
Achieved quarterly OKRs consistently through systematic progress tracking, data analysis, and proactive adjustment of implementation strategies based on performance metrics
Implemented transparent goal tracking dashboards and regular progress communication that enabled team members to understand business objectives and contribute autonomously
Developed data-driven decision-making framework utilizing KPI analysis and impact measurement to prioritize initiatives and optimize resource allocation for goal achievement
Managed end-to-end project delivery as PM through daily standup coordination, critical path identification, and flexible resource reallocation that absorbed schedule delays from parallel production incidents while maintaining original release timeline
Led technical architecture decisions including Tailwind CSS adoption over traditional Sass based on maintainability analysis, and implemented user-focused CMS enhancements through stakeholder interviews to optimize content creator workflows
Proactively expanded project scope to include comprehensive SEO configuration (canonical tags, trailing slashes, meta tags) through self-directed learning and cross-functional collaboration with marketing team, preventing post-launch optimization delays
Orchestrated business model transformation from waterfall to Scrum development, managing cross-functional dependencies and QCDS trade-offs to deliver initial freemium release on schedule with CVR exceeding targets, accelerating paid feature roadmap prioritization
Redesigned authorization architecture by consolidating scattered endpoint permissions into centralized middleware layer with comprehensive authorization mapping documentation, preventing configuration errors and improving implementation transparency during service scaling
Implemented daily KPI monitoring system detecting abnormal application spike patterns, identified low-value freemium conversions inflating advertising costs, and provided data-driven insights enabling marketing team to optimize ad spend allocation and strategy
Designed Apache Hive-compatible partitioning format for archived job data, enabling cost-efficient Athena queries through optimized partition pruning and reducing query costs by organizing data by year/month/day structure
Implemented stream-based CSV file writing to S3 using PHP generators and memory-efficient buffering, preventing memory overflow when processing large datasets while maintaining consistent archive generation performance
Established automated archiving workflow with configurable retention policies, S3 lifecycle management for cost optimization, and comprehensive monitoring to ensure data integrity during deletion and archival processes
Implemented structured data markup enabling job listings to appear in Google Jobs search results, expanding reach beyond traditional search channels and increasing organic traffic
Redesigned sitemap architecture from single-category URLs to multi-language, multi-category coverage at root level, resolving indexing gaps identified through Search Console analysis
Conducted proactive sitemap and index configuration reviews, identifying and resolving issues that SEO specialists had not detected, resulting in 10% session growth through improved crawlability
Developed batch processing programs using PL/SQL and optimized over 1,000 SQL queries
Conducted GoldenGate performance testing comparing Oracle 11g and 19c
Supported 5TB database migration by developing migration scripts
Developed infrastructure as code components using AWS CDK and TypeScript for specific service deployments
Implemented CI/CD pipeline configurations using GitHub Actions for automated infrastructure deployment
Configured monitoring and alerting with CloudWatch for deployed services
Executed ElasticStack upgrade from 7.3.2 to 7.13.1 through comprehensive analysis of all version release notes, GitHub issues, and migration case studies, identifying and resolving configuration changes
Proposed development workflow improvement through complete code migration before architecture changes (instead of concurrent migration), and standardized Presenter layer implementation with unified variable naming conventions enabling micro-architecture benefits while maintaining component reusability
Migrated RPA environment from EC2 to ECS through Docker multi-stage builds and optimized Python container configuration, evaluated and implemented database-backed queue solution based on cost-benefit analysis, and established daily error log monitoring practice for post-launch issue resolution
Financial Systems
Web Development
DevOps & Cloud
Database Engineering
Leadership
Automation
Get In Touch
Whether you have a question, want to discuss a project, or just want to say hello, I'm always happy to connect. Feel free to reach out through any of the channels below.