Senior Backend Developer & Principal E-Commerce Engineer Needed (Contract, 8–12 Weeks)

We're hiring two contract engineers for an 8–12 week engagement on an AWS-based platform: a Senior Backend Developer and a Principal E-Commerce Engineer. Please apply to the role that matches your background and indicate which one you're applying for. Engagement type: Project-based contract Duration: 8–12 weeks Platform focus: AWS Start: ASAP / to be confirmed Rate: $15–65/hr USD, commensurate with experience and location (see tiers below) Location Tiers We're open to candidates across all regions and will evaluate proposals by tier: Onshore: United States / Canada Nearshore: Latin America / Europe Offshore: Rest of world Please note your location and time zone in your proposal. Role A: Senior Backend Developer Architect, build, and evolve a serverless backend stack in AWS, primarily utilizing Python 3.10+, Lambda, CDK, DynamoDB, CloudFront, SNS, SQS, S3, and other related services to support customer-facing applications and internal operational workflows. Required Skills Strong hands-on experience with AWS serverless architecture (Lambda, CDK, DynamoDB, CloudFront, SNS, SQS, S3) Python 3.10+ Experience with GraphQL, OpenAPI, and client SDK generation tools Experience integrating EHR, CRM, eCommerce, and logistics/3PL platforms Preferred Qualifications 2+ years of experience in the healthcare technology industry Experience working in regulated environments involving security, privacy, and compliance requirements Experience with serverless architecture at scale Experience mentoring senior engineers / serving as a technical lead without direct people management responsibility Role B: Principal E-Commerce Engineer Ensure that the integrated systems underlying the end-to-end commerce experience (including Shopify, Stripe, CRM, 3PL, funnel analytics, and marketing attribution) are well designed, well implemented, and operated reliably over time to support near-term commercial growth and long-term platform needs. Required Qualifications 8+ years of software engineering experience, with meaningful depth in ecommerce systems Significant hands-on experience with Shopify, including custom storefront development, APIs, app integrations, and platform limitations Strong experience with Stripe and production-grade payment processing systems Deep understanding of ecommerce architecture, including checkout flows, order lifecycle, refunds, subscriptions, discounts, taxes, and transaction edge cases Experience implementing, maintaining, and operating analytics instrumentation, attribution systems, event tracking, or related marketing technology integrations in production eCommerce environments Experience integrating ecommerce platforms with third-party systems such as ERP, OMS, WMS, CRM, analytics, support, or marketing systems Preferred Qualifications Experience with Shopify Plus Proven track record within rapidly expanding D2C or consumer health retail ecosystems Hands-on proficiency with subscription-based commerce and automated recurring payment structures Strong background in orchestrating and streamlining complex, multi-vendor API ecosystems Experience architecting headless commerce solutions and assessing their strategic viability Experience executing international, multi-brand, or multi-store digital storefront deployments Experience developing asynchronous or event-driven logic for scalable commercial operations Experience operating in strictly regulated, operationally intricate, or high-compliance sectors Experience mentoring senior engineers / serving as a technical lead without direct people management responsibility To Apply, Please Include Which role you're applying for (A or B) Your resume Your location and time zone Relevant project experience, skills, and certifications Your hourly rate expectation Availability and earliest start date