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 …