Founded in 2012, EasyPost is a YC unicorn whose mission is to make shipping simple for businesses—from garage startups to the Fortune 500. EasyPost solves this problem with the first developer-friendly REST API for shipping, and we continue to push boundaries and discover new ways to simplify shipping for all.Position Summary: We’re looking for a Senior Software Engineer to help modernize the technology behind USPS shipping. You’ll join the small, high-trust team that owns EasyPost’s most critical, highest-traffic platform — the USPS PC Postage system — and play a key role in our journey to the cloud. Your Go expertise will help refactor legacy services, design cloud-native solutions, and deliver the low-latency, high-throughput systems our customers count on every day.Essential Duties and Responsibilities:The essential functions include, but are not limited to the following:Build the future - design, code, test, and optimize high-performance Go services that power USPS shipping for millions of users.Drive the migration - help refactor legacy systems for the cloud, then design new cloud-native services that take full advantage of Azure, Kubernetes, Kafka, and more.Collaborate and influence - work hand-in-hand with product managers and other engineers to translate big ideas into rock-solid architecture.Raise the bar - participate in peer reviews, mentor teammates, and bring modern Go best practices (gRPC, microservices patterns, performance tuning) into the codebase.Solve real problems - troubleshoot production issues in high-throughput, low-latency environments without downtime.Document for the future - create clear technical docs so the next engineer can pick up right where you left off.Continuously improve - bring fresh ideas from the industry to improve speed, scalability, reliability, and developer experience.Test like you mean it - build and run automated unit, integration, and performance tests to ensure we ship with confidence.Work smart with tools - use Git and other version control systems to manage complex, distributed workflows.Minimum Education & Experience Qualifications:Bachelor’s Degree8+ years of software development experience, master’s degree and 6+ years of software development experience, or equivalent related work experience. Proven experience in software development, including designing, coding, testing, and debugging applications.Proficiency in Go; experience with additional languages such as Python, C++, or similar is a plus.Familiarity with Agile or Scrum methodologies and tools like JIRA and Confluence.Strong understanding of data structures, algorithms, and design principles.Experience with backend frameworks and APIs; familiarity with front-end frameworks such as React, Angular, or similar is a plus.Knowledge of SQL and NoSQL databases and data modeling concepts.Excellent analytical, troubleshooting, and problem-solving skills.Strong verbal and written communication skills, with the ability to convey complex ideas to technical and non-technical audiences.Core Competencies Required:Big-picture thinker, hands-on builder - you understand how systems fit together and can move seamlessly from high-level architecture to production-ready code, improving what’s there while respecting the work that came before.Creative problem-solver - you thrive on solving complex engineering challenges, weighing trade-offs, and delivering solutions that work in the real world.Collaborative influencer - you connect with teammates across disciplines, earn trust quickly, and know how to communicate ideas that inspire action.Adaptable leader - you’re comfortable in ambiguity, able to chart a path forward, and you elevate the people and projects around you.What We Offer:Comprehensive medical, dental, vision, and life insuranceCompetitive compensation package and equityMonthly work from home stipend of $50Flexible work schedule and paid time offCollaborative culture with a supportive teamA great place to work with unlimited growth opportunitiesThe opportunity to make massive contributions at a hyper-growth companyMake an impact on a product helping ship millions of packages per day