Senior Software Engineer (Python Expert)

🧡📦💙Founded in 2012, EasyPost is a YC unicorn whose mission is to make shipping simple for businesses—from garage startups to the Fortune 500. Shipping, now more than ever, is the backbone of the global economy, but integrating the technology-enabled operations of a modern business with the low-tech and complex shipping industry has always been a challenge. 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. Our team is rapidly growing, and this is the perfect time to get on board. Join us and help build the shipping infrastructure of the future. We’re builders, problem-solvers, and “there has to be a better way” people. We like elegant architecture, fast decisions, and shipping (pun intended) improvements that power millions of deliveries every day. We stay scrappy, we move fast, and we don’t wait for permission to innovate in an industry that desperately needs it. If you want to work on systems that actually move the world—literally—you’re in the right place. 🚚✨   EasyPost does not consider candidates who misrepresent their identity, experience, employment history, or technical qualifications. Applications containing false information, stolen professional profiles, or unverifiable credentials will be removed from consideration. We conduct early-stage verification of resumes, LinkedIn profiles, GitHub accounts, and other relevant professional information as part of our hiring process. Position Summary:  The Senior Software Engineer plays a key role in designing, developing, and operating scalable software solutions that support EasyPost's carrier integrations. This role is expected to independently lead complex technical initiatives, drive engineering best practices, and mentor other engineers while delivering high-quality software. The ideal candidate is an experienced Python engineer who can quickly become productive in a complex distributed environment, navigate ambiguity, and provide technical leadership through influence rather than authority. This individual will partner closely with product managers, engineering leadership, and fellow engineers to deliver reliable, scalable solutions that support business growth and operational excellence. This role requires strong software engineering fundamentals, excellent communication skills, and a demonstrated ability to mentor junior engineers while contributing meaningfully to architecture, design, implementation, and operational support.   Essential Duties and Responsibilities:   The essential functions include, but are not limited to the following:   Technical Leadership o Lead the design and implementation of complex software systems and integrations with minimal oversight. o Drive technical decision-making and contribute to architecture discussions across multiple services and systems. o Break down ambiguous problems into clear technical solutions and execution plans. o Identify technical risks early and proactively propose mitigation strategies.   Software Development o Design, code, test, and debug software applications in accordance with established coding standards and best practices. o Develop scalable, maintainable, and secure software solutions with a focus on performance and reliability. o Collaborate with product managers, designers, and stakeholders to translate business requirements into technical specifications and architectural designs. o Lead technical design efforts and produce high-quality technical documentation. o Develop and execute unit tests, integration tests, and performance tests to validate software functionality and reliability. o Utilize version control systems to manage and track changes to source code.   Mentorship & Team Development o Mentor and coach junior and mid-level engineers through code reviews, design discussions, pairing sessions, and day-to-day collaboration. o Raise engineering quality by promoting best practices in software design, testing, observability, and operational excellence. o Provide constructive technical feedback and help establish consistent engineering standards across the team. o Participate in code reviews to maintain code quality, ensure consistency, and share knowledge among team members.   Operational Ownership o Participate in on-call rotations and assist in diagnosing and resolving production issues. o Drive improvements in monitoring, alerting, observability, and system reliability. o Investigate complex production issues and lead root cause analysis efforts. o Identify and troubleshoot software defects and issues, employing analytical thinking and problem-solving skills to develop efficient and effective solutions.   Collaboration & Continuous Improvement o Work closely with cross-functional teams to ensure seamless integration of software components and successful product releases. o Contribute to project planning, estimation, and technical roadmap discussions. o Stay current with industry trends, emerging technologies, and software development best practices. o Propose and implement process improvements that enhance development efficiency, reliability, and product quality.   Minimum Education & Experience Qualifications: o Bachelor's degree in Computer Science, Engineering, or a related field, or equivalent practical experience. o 6+ years of professional software engineering experience. o Demonstrated experience leading complex technical initiatives from design through production deployment. o Demonstrated experience mentoring and developing other engineers. o Expert-level Python development experience in production environments. o Strong experience designing and building REST APIs and distributed systems. o Strong experience debugging and troubleshooting complex production issues. o Strong experience with relational databases and SQL. o Experience designing scalable, maintainable, and observable backend services. o Experience writing automated unit, integration, and end-to-end tests. o Familiarity with software development methodologies (Agile, Scrum, etc.) and tools (JIRA, Confluence, etc.). o Strong understanding of data structures, algorithms, object-oriented design principles, and software architecture patterns. o Excellent problem-solving skills and a detail-oriented mindset. o Strong written and verbal communication skills.   Preferred Qualifications o Experience with carrier, logistics, shipping, payments, fintech, or other API-intensive domains. o Experience with cloud platforms, preferably AWS. o Experience with monitoring, observability, and alerting tools. o Experience working within service-oriented or microservice architectures. o Experience working with high-volume, highly available production systems.   Core Competencies Required: o Knowledge and Application: Exhibits advanced wide-ranging experience, using in-depth professional knowledge, acumen, concepts and company objectives to develop, resolve complex models and procedures. Provides solutions to issues in creative and effective ways. Understands the interrelationships of different disciplines. Directs the application of existing principles and guides development of new policies and ideas.   o Complexity & Problem Solving: Understands and works on complex issues where analysis of situations or data requires an in-depth evaluation of variable factors. Determines methods and procedures on new assignments. Exercises judgment in selecting methods, evaluating, adapting of complex techniques and evaluation criteria for obtaining results. Work is reviewed upon completion and is consistent with departmental objectives.   o Collaboration & Interaction: Networks with key contacts outside their own area of expertise. Adapts style and uses persuasion in delivering messages that relate to the wider firm business. Frequently advises others on complex matters. May be accountable through the team for delivery of tactical business targets.   Physical Demands and Work Environment:  The physical demands described here are representative of those that must be met by an employee to successfully perform the essential functions of this position. Reasonable accommodation may be made to enable individuals with disabilities to perform the functions.   Physical Requirements: o Minimal to light physical effort is required in performing duties. o Prolonged stationary periods at a desk and working on a computer. o Extensive use of computers, keyboards, and communication-based technology to exchange information.