Junior Backend Engineer (App Delivery)

Cogna; Greater London; Hybrid; GBP 80,000 - 100,000; Full time

Job summary

A technology company for industries seeks a Backend Engineer to join their team in London. You'll build and maintain backend features and API integrations using Python and SQL. This role offers opportunities in AI-assisted development and collaborative projects, ensuring impactful contributions within critical sectors. The company offers competitive salaries, flexible working, 25 days annual leave, and excellent benefits including healthcare and pension plans.

Benefits

Competitive salary and share option plan

25 days annual leave plus public holidays

Excellent pension scheme, fixed at 7.5%

Private healthcare including family cover

Flexible hybrid working

Access to a gym and fitness classes

Qualifications

• 1+ years experience with Python or TypeScript.
• Understanding of SQL and data modeling.
• Experience with REST APIs is required.

Responsibilities

• Build and maintain backend features and API integrations.
• Adapt and extend pipelines and front-end outputs.
• Collaborate with teams on AI-assisted development.

Skills

Python

TypeScript

SQL

APIs

Git

Docker

AI coding tools

Tools

FastAPI

CI/CD pipelines

Azure

AWS

GCP

Job description

We live in a world that runs on physical industries like energy, logistics, manufacturing. These sectors are essential to our economy and daily lives, yet they are held back by inefficiencies, fragile legacy systems, and decades-old ways of working. This is not just a business problem; it is a societal one. When grids fail, supply chains stall, or factories falter, entire economies are disrupted.

These companies face unique, complex challenges that typical software was never designed to solve. Cogna was founded to change this. Our mission is to give critical industries their own AI-powered Software Factory: a way to build and deploy bespoke digital tools that solve pressing operational challenges.

Since our launch in May 2023, we’ve seen incredible customer traction and revenue growth. We’re backed by leading VCs, including Notion Capital and Hoxton Ventures, and we’re building a world-class team to take on one of the most important challenges of our time.

Tackling challenges at this scale takes people who are curious, adaptable, and motivated by impact. If our mission resonates with you, we encourage you to apply, even if your experience doesn’t match every requirement. We are committed to building a diverse team that reflects the industries and societies we serve.

Overview

Join a team that is redefining how software is built for critical industries. You will help build and maintain the backend services and integrations that power our SaaS applications, working with modern tech stacks and cutting-edge AI tools. This role is an opportunity to accelerate your growth: you will learn to build robust production systems and master AI-assisted development workflows, focusing on validating logic and delivering high-quality features that solve real-world problems.

What you’ll do

• Build and maintain backend features and API integrations (Python, FastAPI, SQL).
• Adapt and extend pipelines and front-end outputs, validating automated components.
• Build connectors for APIs, files, and external systems.
• Support the integration of LLM-based capabilities with robust evaluation and monitoring.
• Use AI-assisted development tools to scaffold, refactor, and test code.
• Collaborate with Solution Strategists, Data Platform, Platform and Support teams.

What we’re looking for

We don't expect you to have deep expertise in all these areas. We look for a solid foundation in backend engineering and a strong curiosity to learn the rest.

• Python/TypeScript experience (1+ years or strong personal projects); understanding of SQL and data modelling.
• Familiarity with (or keen interest in) agentic AI coding tools (e.g., Cursor/Codex/Claude Code) to plan, scaffold, refactor, and test.
• Experience with APIs (REST) required. Exposure to other systems like SFTP, SharePoint, or webhooks is a plus.
• Interest in or exposure to workflow orchestration (Temporal, Dagster).
• Basic familiarity with git, CI/CD concepts, Docker, or cloud platforms (Azure/AWS/GCP).
• Interest in AI and raising team AI skills.

What we offer

• Competitive salary and share option plan
• 25 days annual leave, plus public holidays
• Excellent pension scheme, fixed at 7.5%
• Private healthcare, including family cover and pre-existing conditions
• Flexible hybrid working with 2 days per fortnight in our Farringdon office
• Regular social events and offsites
• Access to a gym and fitness classes in our office building