Charles Ouimet

Member of the shop.app Buyer Acquisition (growth) team, focused on the Shop Cash domain. Designed an affiliate payout program in the AdTech/growth space and contributed to the shop.app ecosystem migration to distributed SQL.

• Owned the migration of one of the highest-QPS tables (top 20) to YugabyteDB as part of the shop.app ecosystem transition to distributed SQL.

• Designed an affiliate payout program in partnership with impact.com and implemented the foundational pieces.

• Built custom Claude Code commands to automate repetitive tasks and developed a Claude skill for ATC (Air Traffic Controller) support rotation that leveraged multiple MCP integrations to collect data and guide decisions based on team runbooks.

• Made my first open source contribution to the smart_todo Ruby gem, adding a context attribute referencing GitHub issues.

Dove into the crypto and DeFi space, gaining hands-on knowledge across EVM-compatible chains and Solana. Decomposed a monolith into microservices, modernized the monorepo toolchain, and built company-wide observability infrastructure.

• Extended a fork of the SonarWatch Portfolio by implementing the Stader protocol and peer-reviewing other protocol integrations, exploring independence from Debank's API for on-chain portfolio data across multiple EVM-compatible chains and Solana.

• Decomposed parts of a monolith into independent microservices to improve scalability and reduce resource contention.

• Simplified dependency management of shared packages by converting monolithic npm packages to a Turborepo monorepo using changesets and automated releases.

• Reduced CI/CD duplication and improved pipeline consistency across repos by creating shared GitHub actions and workflows.

• Prevented third-party API throttling from impacting portfolio data availability by developing reusable infrastructure for resilient request management.

• Eliminated fragmented logging across microservices by implementing structured logging adopted company-wide, giving teams centralized observability and faster issue investigation through AWS CloudWatch Log Insights and custom metrics. Layered request tracing on top with correlation_id and request_id propagation through HTTP headers via Axios interceptors.

Focused on cross-cutting initiatives across the post-acquisition Flexport platform while staying close to the prep team from Deliverr days. Drove cross-AWS-account integrations, expanded the transactional outbox pattern and distributed tracing, and led modernization of the internal npm ecosystem and AWS SDK migration. Gained knowledge in global logistics and supply chain.

• Supported post-acquisition platform integration by guiding design and code reviews for cross-AWS-account SQS message flow between Flexport Core's freight-forwarding systems and the ex-Deliverr fulfillment business (omni-channel, DTC and B2B), and for the parcel team's integration with the duties team under the US Section 321 framework.

• Expanded the transactional outbox pattern across the inbounds domain family by sponsoring a Senior developer's foundation work, reverse-engineering the shipments lifecycle into state diagrams, and steering downstream consumption by crossdock and prep domains. Replaced the prior CDC approach with business-significant integration events.

• Improved service observability by extending the Shopify-Logistics-era observability-as-code initiative (broadening the monitors.json DSL past serverless) and building distributed tracing with correlation_id and request_id propagation through HTTP headers via reusable Axios interceptors, SQS message metadata, and Kinesis Data Stream events. Those additions improved end-to-end debug capability in DataDog across the distributed ecosystem.

• Enabled low-friction modernization of 80+ microservices by building the foundation of an AWS SDK v3 compatibility layer that kept method signatures compatible with previous AWS SDK v2 integration.

• Modernized the internal npm ecosystem by introducing peerDependencies (cutting Lambda bundle sizes and cold-start delays) and resolving circular dependencies across the package graph.

Continued leading the prep team after Shopify acquired Deliverr, actively coding new features while providing technical direction. Beyond the team, drove cross-cutting initiatives in observability, API design, and cross-cloud eventing standards as a member of the Technical Leadership Community (TLC).

• Served on the Technical Leadership Community (TLC), a group of 8-10 leaders from across Shopify Logistics' sub-divisions meeting weekly. Acted as a sounding board for system design validation across the combined ~250-developer organization and built presentations on patterns including the transactional outbox and sagas (orchestration vs. choreography).

• Co-authored an observability spec defining three pillars (availability, throughput, latency) and implemented observability-as-code for the inbounds sub-org's serverless services. Built a monitors.json DSL with automation that generated tagged DataDog monitors and SLOs with per-environment thresholds. Published the reference implementation (Koa middlewares, Lambda wrappers) as a standalone npm package after incubating it in the prep service.

• Contributed to the prep portion of the Logistics API, a single point-of-entry API that centralized authn/authz, rate limiting, and orchestration for internal and external partners in place of exposing 60+ microservices directly.

• Facilitated cross-team conversations on domain boundaries and sources of truth using EventStorming and BPMN, advocating event-driven architecture with integration events over direct API calls and CDC reverse-engineering.

• Contributed to TLC specifications for cross-cloud (AWS ↔ GCP) eventing standards between Shopify Logistics and the rest of Shopify, building on Shopify's Monorail format and the prior Deliverr integration-events specification. Scope spanned merchants, products, and the fulfillment-center pick-pack-ship process.

Founding member of the prep team. The prep service incubated patterns — DDD, finite state machines, transactional outbox, and integration events — that ~10 existing services progressively adopted and that became the default for new services via the GitHub template repo.

• Founded the prep team (4 engineers, growing to 8) and led the pivot from a CRUD MVP to a DDD service with a finite state machine enforcing the prep-job lifecycle. Used EventStorming and BPMN to map workflows with engineering, product, and business stakeholders. The POC started inside the existing inbound microservice, then spun off into its own standalone service using the strangler pattern.

• Authored the original integration events specification for the Deliverr ecosystem — naming convention, versioning, and a shared npm skeleton. The pattern was adopted by multiple teams as the foundation for inter-service communication.

• Incubated the transactional outbox pattern as the first service in the ecosystem to implement it. Solved the two-phase commit problem (DB transaction commit + message emit) and replaced the prior CDC reverse-engineering approach. Used SNS fan-out on the publishing side so any domain could subscribe without the publishing service needing to know about them.

• Created @deliverr/eslint-config, a private npm package that centralized linting across 40+ services and the shared-packages monorepo. Ended per-project style drift through a backwards-compatible adoption path with SemVer releases. Retrofitted into the GitHub template repo, making it the default for new services.

• Used the prep service as an incubator for patterns later adopted ecosystem-wide — inversify for dependency injection (first use at Deliverr), domain probes for business-significant observability (first adoption in the ecosystem), anti-corruption layers, and a monorepo structure with three independently-versioned packages.

• Maintained shared npm packages (transactional outbox, integration events, TSOA, CDC pipelines, serverless components) and regularly reviewed PRs and technical design documents across teams.

Tech Lead during SSENSE's international expansion from a single Montréal fulfillment center to a second facility in Europe. Served on the Technology Architecture Group (TAG) and led the distributed, fully-serverless OMS peel-off and a CBSA export-declaration system. Hired as Senior Developer in October 2019; promoted to Tech Lead in August 2020.

• Served on the Technology Architecture Group (TAG), a 6-10 person group of architects and Staff Engineers that set the department's tech standards. Oversaw projects from 3 other teams through design reviews and architecture consults.

• Led the OMS peel-off from the company's monolith to support international expansion to a second fulfillment center. Reverse-engineered legacy order-handling code into BPMN documentation of the full order lifecycle over 3-4 weeks, then designed the distributed serverless replacement using DDD context maps, hexagonal architecture, and a finite state machine. Orchestrated the customer order lifecycle with AWS Step Functions across smaller-scoped Lambdas.

• De-risked the OMS cutover by designing an async shadow-order pipeline (API Gateway + JSON Schema + SQS) that mirrored every production order to the new system with near-zero added latency. The checkout service never awaited the shadow call; replay from DLQ was available whenever a shadow request hit a bug.

• Designed and guided implementation of a purely serverless CBSA export declaration system. Used the C4 model for documentation, DynamoDB Streams for event processing, and SOAP for 3rd-party API integration.

• Contributed full-stack to the Product Information Management system (Python backend) and the Purchase Orders platform (React + Redux frontend) as a Senior Developer before promotion to Tech Lead in Aug 2020.

Improved REST API micro-services in the Paper Products Division of the e-commerce platform, maintaining backwards-compatibility through feature flags in a trunk-based development workflow. Technologies: Java, Hibernate, Guice, Mockito, AWS.

Provided long-term vision for the evolution of a SaaS REST application and standardized private and public APIs (payload and URL consistency, versioning). Conducted rigorous code reviews and trained team members in the craft. Supervised an offshore team of up to 9 developers in India. Hired as Senior Developer; promoted to Architect in 2014. Technologies: Java, Hibernate, Spring, Mockito, Jenkins, Artifactory, SQL Server, SSAS, OLAP, ETL.

Provided architectural guidance and served as XML subject matter expert for the department. Standardized exchange formats between layers of the network management system using XML. Conducted needs assessments, prototype presentations, and code reviews. Hired as Developer; promoted to Senior Developer in 2011.

Remote role for this Santa Ana, California-based company. Led functional analysis and implementation with API maintenance and extension. Supervised developers located in Europe and the United States.

Voted by engineering peers for the highest-impact contribution from a developer who joined Deliverr in the prior year.

Won the engineering department hackathon with an idea to improve the onboarding experience of new developers, later developed into an automated toolchain.

Recognized as one of Canada's 50 most influential people in graphic communications.

• Composable skill system covering the full issue lifecycle from blank issue to merged PR

• Published on the VS Code Marketplace under the MIT license

Volunteer parent supporting Cadets during weekly meetings with whatever duties needed attention.

Chaired CIP4's preflight sub-committee, contributing to industry standards for print workflow automation and quality control.