Senior Backend Engineer, Conversations AI

Postscript is redefining marketing for ecommerce companies. By introducing SMS as an entirely new channel for ecommerce stores to engage, retain, and convert their customer base, brands are seeing huge ROI with Postscript. Backed by Greylock, Y Combinator and other top investors, Postscript is growing fast and looking for remarkable people to help build a world class organization. To learn more about postscript, checkout this article from one of our investors, Greylock, on our vision for the Future of Marketing.

At Postscript, we’re leveraging AI to revolutionize SMS performance, driving measurable revenue gains through continuous self-improvement, proven by real-time testing. As the online shopping landscape grows, the demand for scalable, personalized customer engagement solutions is unprecedented.

As a Senior Backend Engineer on the Conversations AI Team, you’ll be at the forefront of innovation, using your expertise in OpenAI, Large Language Models (LLMs), and Retrieval-Augmented Generation (RAG) to push the boundaries of conversational AI. You’ll architect, build, and refine systems that enable our AI agents to learn, adapt, and deliver personalized shopping experiences that scale to millions of users. Your work will have a direct impact on Postscript’s bottom line and our customers’ success by helping SMS become their most powerful revenue channel.

This role offers a unique opportunity to influence how AI can drive next-level customer engagement and guide the team in crafting solutions that combine technical excellence with business value.

What You’ll Do:

• Architect, build, and maintain scalable, high-performance APIs for our AI-driven conversational tools, ensuring seamless and efficient customer interactions via SMS.
• Work closely with cross-functional teams to integrate LLMs, OpenAI models, and RAG techniques into our AI platform, driving personalized, real-time customer engagement.
• Lead the design and deployment of highly available, modular, and scalable backend systems on AWS, using Python (Flask) and other modern technologies.
• Innovate on acquisition tools that collect valuable customer data and contribute directly to the growth of our clients’ SMS subscriber lists.
• Own the implementation of new AI features from start to finish, collaborating with product managers and designers to deliver customer-focused solutions.
• Mentor and guide other engineers, fostering a culture of continuous improvement and learning.
• Lead with technical excellence, balancing the need for immediate solutions with long-term scalability and maintainability.

What We’re Looking For:

• Strong experience working with OpenAI, LLMs, and RAG, with a passion for implementing cutting-edge AI-driven solutions.
• Minimum 6-8 years professional software development experience, with 1-2 years at minimum in AI solutions
• Proven track record of building and scaling backend systems, ideally in high-growth or early-stage environments.
• Expertise in Python (Flask, SQLAlchemy) and building robust, modular APIs, with a focus on extensibility and performance.
• Deep understanding of relational databases, data modeling, and AWS architecture, with a focus on high observability and scalability.
• Ability to lead app projects from conception to delivery, managing ambiguity, and driving results.
• Experience mentoring and leading engineering teams, with a collaborative mindset and excellent communication skills.
• Familiarity with modern frontend technologies (TypeScript, Lit Web Components) and a willingness to work across the stack as needed.

What We’ll Love About You

• You’re curious and enthusiastic—you love building things
• Energized by early stage companies and the opportunity to own and improve a new, fast-growing codebase
• You can drive technical decisions by measuring trade offs informed by both business priorities and technical needs
• You have empathy for users and enjoy helping others
• Bonus: Remote work experience. You love working on a remote-first team

What You’ll Love About Us

• Salary range of USD $170,000-$200,000 base plus significant equity (we do not have geo based salaries)
• High growth startup - plenty of room for you to directly impact the company and grow your career!
• Work from home (or wherever)
• Fun - We’re passionate and enjoy what we do
• Competitive compensation and opportunity for equity
• Flexible paid time off
• Health, dental, vision insurance

You are welcome here. Postscript is an ever-evolving place of equal employment for talented individuals.