Senior Software Engineer (C# / PostgreSQL / AI-Native) at zendbox

Paddock Wood, England, United Kingdom -

Full Time

Start Date

Immediate

Expiry Date

17 May, 26

Salary

0.0

Posted On

16 Feb, 26

Experience

5 year(s) or above

Remote Job

Yes

Telecommute

Yes

Sponsor Visa

Skills

C#, PostgreSQL, AI-Native, .NET 10, C# 14, Agentic Systems, Agent Loops, LLMs, Azure, AWS, Blazor, Azure ML, Claude Code, Cursor, GitHub Copilot

Industry

Logistics;Transportation;Supply Chain and Storage

Description

We have a working AI Proof of Concept (PoC) that proves our vision; now we need the engine that powers the product at scale. As our Senior Software Engineer, you will be the lead architect and primary builder of our production-grade, AI-first .NET platform. Working directly with the Head of Technology, you will be responsible for moving us from experimental scripts to a robust, observable, and scalable Agentic AI Architecture. We are a high-velocity team that values "Ship Fast, Fix Fast." We utilize agentic AI tools like Claude Code to bypass the boilerplate, freeing you to focus on the high-value architectural challenges of a production-ready system. What You’ll Do Productionize AI Workflows: Transform raw AI prompts and experimental logic into resilient production code using .NET 10/C# 14. Architect Agentic Systems: Design and build the "Agent Loops" (Planning → Execution → Observation) that allow our AI to interact reliably with our internal databases and external APIs. Build for Reliability: Implement "Evals" and Guardrails to manage the non-deterministic nature of LLMs, ensuring outputs are safe, accurate, and consistent for our users. Cloud Infrastructure: Partner with the Head of Tech to design and deploy the Azure/AWS infrastructure required to support high-concurrency AI workloads, focusing on latency and cost-per-token optimization. AI-First Tooling: Lead the team in adopting and optimizing AI-assisted development workflows (Claude Code, Cursor, etc.) to maintain our 10x velocity. Strategic Evolution: Collaborate on the long-term technical roadmap, identifying when to use fine-tuned Small Language Models (SLMs) vs. Frontier LLMs. The "Must-Haves" C# Mastery: You are an expert in the modern .NET ecosystem. PostgreSQL Expert: You know how to design schemas, optimize queries, and leverage Postgres for high-performance applications. Architectural Thinker: You can look at a PoC and know exactly what it needs to survive 100x the current load. The "Bonus Points" (Will make you stand out) Blazor: Experience with Blazor (Server or WebAssembly) for building real-time UIs. Azure ML: Any exposure to Azure Machine Learning services or deploying ML models into a production pipeline. AI Workflow: You already use Claude Code, Cursor, or GitHub Copilot in your daily flow.

Responsibilities

The Senior Software Engineer will act as the lead architect and primary builder for scaling an AI Proof of Concept into a production-grade, AI-first .NET platform, focusing on robust, observable, and scalable Agentic AI Architecture. Key tasks include productionizing AI workflows, designing Agent Loops for reliable AI interaction with databases and APIs, and implementing guardrails for LLM outputs.