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Hello! I'm Jacob Ham, a Senior Full Stack Engineer with 9+ years of experience designing, building, and scaling high-traffic web apps and e-commerce platforms. I love turning complex problems into reliable, maintainable software and collaborating with product, design, and QA to deliver delightful user experiences. I mentor junior developers, lead technical direction, and advocate for clean code, strong testing, and scalable architectures. When I'm not coding, I enjoy exploring new technologies, sharing best practices with my team, and helping fast-paced organizations ship high-quality software.…Hello! I'm Jacob Ham, a Senior Full Stack Engineer with 9+ years of experience designing, building, and scaling high-traffic web apps and e-commerce platforms. I love turning complex problems into reliable, maintainable software and collaborating with product, design, and QA to deliver delightful user experiences. I mentor junior developers, lead technical direction, and advocate for clean code, strong testing, and scalable architectures. When I'm not coding, I enjoy exploring new technologies, sharing best practices with my team, and helping fast-paced organizations ship high-quality software.

Jacob Ham

Full Stack Developer, Back-End Developer, Web Developer, +4

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Hello! I'm Jacob Ham, a Senior Full Stack Engineer with 9+ years of experience designing, building, and scaling high-traffic web apps and e-commerce platforms. I love turning complex problems into reliable, maintainable software and collaborating with product, design, and QA to deliver delightful user experiences. I mentor junior developers, lead technical direction, and advocate for clean code, strong testing, and scalable architectures. When I'm not coding, I enjoy exploring new technologies, sharing best practices with my team, and helping fast-paced organizations ship high-quality software.…Hello! I'm Jacob Ham, a Senior Full Stack Engineer with 9+ years of experience designing, building, and scaling high-traffic web apps and e-commerce platforms. I love turning complex problems into reliable, maintainable software and collaborating with product, design, and QA to deliver delightful user experiences. I mentor junior developers, lead technical direction, and advocate for clean code, strong testing, and scalable architectures. When I'm not coding, I enjoy exploring new technologies, sharing best practices with my team, and helping fast-paced organizations ship high-quality software.

Available to hire

Hello! I’m Jacob Ham, a Senior Full Stack Engineer with 9+ years of experience designing, building, and scaling high-traffic web apps and e-commerce platforms. I love turning complex problems into reliable, maintainable software and collaborating with product, design, and QA to deliver delightful user experiences.

I mentor junior developers, lead technical direction, and advocate for clean code, strong testing, and scalable architectures. When I’m not coding, I enjoy exploring new technologies, sharing best practices with my team, and helping fast-paced organizations ship high-quality software.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Language

English

Fluent

Javanese

Advanced

Work Experience

Senior Software Engineer, Tech Lead at Accenture

March 1, 2015 - December 1, 2025

Led backend engineering and tech leadership for checkout platforms, achieving a 28% reduction in API p95 latency through Laravel refactors, payload shaping, and Redis caching with explicit invalidation on cart/price updates. Drove 2.1x throughput for checkout events during promos via AWS SQS decoupling and tuned ECS/Fargate workers with backpressure. Improved payment safety with idempotency keys, webhook verification, dedupe constraints, and DLQ replay tooling. Lowered MySQL read load by 40% through indexing and query rewrites; enhanced release confidence with GitHub Actions gates and expanded PHPUnit coverage; reduced MTTR through correlation IDs, dashboards, and Sentry triage. Automated safe backfills and reconciliations with Python CLI tools and enforced contract checks with OpenAPI validation in CI. Standardized SQS/IAM/CloudWatch via Terraform modules; created scripted incident runbooks to reduce on-call cognitive load. Implemented UI improvements in React + TypeScript for checkou

Senior Software Engineer at Square

February 1, 2022 - March 1, 2025

Improved entitlement API responsiveness and consistency with PHP/Symfony components, payload optimization, and Redis invalidation, boosting conversion. Increased resilience during traffic spikes by offloading with SQS/RabbitMQ, tuning concurrency, and enforcing timeouts/retries. Reduced database load via indexing and N+1 elimination with PostgreSQL and EXPLAIN-driven rewrites. Expanded PHPUnit coverage and gated CI with GitHub Actions to reduce regressions. Strengthened observability with structured logging, correlation IDs, and New Relic/Datadog dashboards. Aligned payload schemas with OpenAPI and added webhook verification with replay-safe processing for out-of-order events. Right-sized compute by moving hot reads to Redis and adjusting autoscaling. Improved access-state UX in React + TypeScript and automated exports to S3 via scheduled Python jobs. Standardized operational workflows with Bash scripts for log capture and environment checks.

Software Engineer at Amazon

September 1, 2013 - February 1, 2022

Reduced WISMO contacts and improved delivery trust by increasing shipment-tracking accuracy through Laravel/Lumen ingestion with normalization and MySQL dedupe. Increased throughput of RabbitMQ/SQS workers with tuned concurrency, retries, and dead-letter handling; reduced stale tracking states with Redis hot reads and invalidation on state transitions. Hardened payload handling with schema validation and webhook verification, and implemented replay-safe processing for out-of-order updates. Optimized tracking/returns flows by indexing and removing N+1 bottlenecks; expanded PHPUnit coverage through refactoring legacy modules into testable services. Improved onboarding and local development via Docker Compose; early payload validation using Node.js utilities aligned to OpenAPI.

Senior Software Engineer, Tech Lead at Accenture

March 1, 2025 - December 1, 2025

Led a cross-functional team to deliver customer-facing React applications using TypeScript and component-driven design; owned the frontend state and data flow, implemented CI/CD pipelines with GitHub Actions, and improved performance with code-splitting and lazy loading; collaborated on API contracts, documented OpenAPI specs, and established automated UI/integration tests and observability.

Senior Software Engineer, Senior Full Stack Engineer at Square

February 1, 2022 - March 1, 2025

Designed and built responsive SPAs with React/TypeScript; integrated RESTful Node.js/Express microservices with PostgreSQL and MongoDB; migrated legacy JS to TypeScript; built CI/CD workflows and introduced feature-flag releases; implemented frontend performance budgets, observability dashboards with Prometheus and Sentry; mentored engineers and authored API docs; contributed to on-call rotations and production incident response.

Software Engineer, Full Stack Engineer at Amazon

September 1, 2013 - February 1, 2022

Delivered customer-facing features across frontend and backend stacks using JavaScript, HTML5 and CSS3; designed backend services with Node.js and Java exposing RESTful APIs for SPAs; built scalable service components in a service-oriented architecture, integrating with AWS services for compute, storage and messaging; contributed to database design with PostgreSQL and DynamoDB, implemented caching, automated tests, performance profiling, and secure token-based authentication; managed rollout procedures and blue/green deployments; instrumented services with logging and metrics for SLO/ SLA monitoring.

Senior Software Engineer | Senior Full Stack Engineer at Square

February 1, 2022 - March 1, 2025

Designed and built responsive SPAs with React and TypeScript, translating UX designs into modular components and design tokens. Implemented RESTful API integrations with Node.js/Express microservices and collaborated on database schema design using PostgreSQL for transactional data and MongoDB for document stores. Led migration of legacy JS modules to TypeScript, improving type safety across the codebase and reducing runtime errors. Built CI/CD workflows (CircleCI/GitHub Actions) to automate testing, build artifacts and safe rollouts; introduced feature-flag driven releases for incremental user exposure. Optimized client-server interactions by batching requests, introducing caching strategies and using efficient JSON payloads to reduce latency and bandwidth. Established frontend performance budgets and used Lighthouse audits to prioritize improvements across critical journeys. Integrated authentication flows and secure token storage patterns, working closely with security teams to meet

Software Engineer | Full Stack Engineer at Amazon

September 1, 2013 - February 1, 2022

Worked across frontend and backend stacks to deliver customer-facing web features using JavaScript, HTML5 and CSS3, ensuring cross-browser compatibility and responsive behavior. Designed and implemented backend services using Node.js and Java, exposing RESTful APIs consumed by single-page frontends. Built scalable service components in a service-oriented architecture, integrating with AWS services for compute, storage and messaging. Contributed to database design and queries using PostgreSQL and DynamoDB for different workload patterns; implemented caching layers to reduce database load. Introduced automated unit and integration tests and expanded test coverage to reduce regressions. Collaborated on performance debugging and profiling, optimizing hot paths and improving throughput under load. Implemented secure communication and authentication patterns for internal and external APIs, following best practices for token lifecycles. Owned rollout procedures and blue/green deployments, par

Senior Full Stack Engineer & Tech Lead at Accenture

February 1, 2022 - March 1, 2025

Led a team of engineers to deliver critical e-commerce checkout and payment features on time and within scope, providing technical direction and conducting regular code reviews to maintain engineering standards. Designed and built scalable checkout APIs and backend services using PHP 8.2/Laravel and Redis, reducing API latency and improving throughput. Implemented event-driven workflows with AWS SQS, tuned ECS/Fargate workers, and expanded Terraform modules for SQS and CloudWatch alarms. Improved MySQL reliability with deduplication constraints and idempotency, added webhook verification, and dead-letter replay. Replaced legacy modules with testable services and expanded PHP Unit coverage, resulting in fewer defects.

Senior Software Engineer at Square

March 1, 2025 - December 1, 2025

Designed and maintained entitlement APIs and backend services using PHP (Symfony components), improving API responsiveness and consistency through refactors, payload optimization, and Redis caching. Increased checkout throughput by 2.1x without proportional infrastructure growth; implemented ECS/Fargate-based monitoring and CloudWatch alerts. Standardized local development environments with Docker Compose and automated CI/CD pipelines; enforced API contract validation using OpenAPI specs; introduced guardrails to prevent breaking changes.