Senior Software Engineer

Personio GmbH; Greater London; Hybrid; GBP 125,000 - GBP 150,000; Full time

Job summary

A technology company based in London is seeking a Senior Software Engineer with experience in Golang and AWS to build and maintain its data processing platform. Responsibilities include realtime call risk analysis and integration with various teams. The position offers a hybrid working style and numerous benefits like extensive health insurance, paid parental leave, and a discretionary annual bonus of up to 10%. Candidates should have strong communication skills and be comfortable mentoring team members.

Benefits

Hybrid working style

Extensive health insurance

Paid parental leave

Life insurance

Annual bonus of up to 10%

25 days annual leave plus bank holidays

Qualifications

• Several years of experience as a senior engineer designing services for enterprise customers.
• Familiarity with infrastructure-as-code tools like AWS CloudFormation.
• Open to mentoring team members and receiving feedback.

Responsibilities

• Build and maintain a cloud-based data processing platform.
• Conduct real-time call risk analysis.
• Collaborate with different teams on architecture and integration.

Skills

Golang

AWS

CI/CD pipelines

Excellent communication

Agile principles

Tools

Docker

GitHub

Jira

CircleCI

Job description

About Smartnumbers

We are on a mission to stop fraud and improve customer authentication. Fraud is a huge problem affecting millions of people, it costs the UK nearly £7bn and represents 40% of all crime.

We are changing this by providing organisations with real‑time insight into the risk of a caller. We combine patented machine learning technology with our deep domain knowledge to prevent contact centre fraud.

We recognise that we need to work together to fight fraud, that is why we have fostered strategic partnerships with leading global organisations like Amazon, BT, Genesys and NICE. Together, we protect the UK’s largest retail banks, investment banks and emergency services. We also believe in developing our people and developing high performing teams, reflected by our Platinum Investors in People accreditation.

What you'll be working on

Our solution enables customers to give genuine callers a seamless experience in the contact centre at the same time as stopping fraudsters. We do this by authenticating legitimate callers and identifying suspicious calls pre‑answer, and analysing their behaviour during the call to provide insight after the call has ended. You will play a key part in achieving our company vision: “to make voice communications safer”.

Reporting to a Principal Software Engineer, you will be responsible for building and maintaining our cloud‑based data processing platform that covers the following activities:

• Realtime call risk analysis
• Maintaining and improving a large microservice architecture
• Integrating with different teams within Smartnumbers
• Database technologies including data warehousing
• Receiving and sharing real‑time audio streams

Technologies, tools, and principles

Back End Technologies

• Languages: Golang
• Compute: Lambda, ECS/Fargate/Docker, EC2
• Asynchronous Processing: SQS, SNS, EventBridge, Kinesis Data Streams
• Datastores & Analytics: DynamoDB, S3, Redshift, Athena, Glue
• Other Services: KMS, IAM, CloudWatch

Development & Deployment Tooling

• GitHub, Copilot, Artifactory
• AWS CDK & CloudFormation
• CircleCI
• Jira

Programming/Architecture Principles

• Event driven systems design
• TDD, BDD
• HTTP/REST API design
• Single-table database design
• SOLID principles
• Awareness of best practises around non‑functional requirements (security, analytics, maintainability of code, performance, monitoring/observability)

Front End Technologies (not required, but beneficial)

• Typescript
• React (Storybook, Webcomponents)
• Angular (NgRx, RxJS)
• Material UI
• Cypress/Playwright (E2E & Integration Testing)

What you'll need for the role

• Several years of commercial experience in a senior engineer position designing, building and maintaining services for enterprise customers using Golang & AWS
• Experience with infrastructure‑as‑code (ideally AWS CloudFormation, AWS CDK)
• Familiarity with CI/CD pipelines and containerization
• Excellent verbal and written communication
• Open collaboration with engineering and broader business teams
• Receptive to feedback, learning and self‑development
• Good understanding of agile principles and Kanban methodology
• Attention to detail and quality of work is of paramount importance
• Happy to mentor less experienced members of the team

What we can offer you

• Hybrid working style, with the expectation of two days in the office (with a great City of London office base!)
• Family friendly benefits including paid parental leave policies
• An extensive health insurance policy for you, with an option to add your family members
• A workplace pension with Hargreaves Lansdown
• Life insurance of 4 x your salary
• A discretionary annual bonus of up to 10% of your salary
• Weekly self‑development time to spend exploring your professional development interests
• 25 days of annual leave (plus bank holidays), your birthday off, and an opportunity to buy up to 5 days annual leave per year
• A holistic wellbeing support plan encompassing a variety of offerings to assist you. We provide you with a monthly £50 allowance to fund activities to best support your wellbeing as well as workshops and training to provide tools and guidance. Additionally, there is a wide-ranging employee assistance programme available to advise on personal, family or financial matters, and also fun social events during the year.

The application process

Screening interview with the hiring manager, take‑home coding assessment, technical and competency‑based interview, culture & values interviews with HR and bar‑raiser.

Equal Employment Opportunity

Smartnumbers is committed to promoting equal opportunities in employment. You will receive equal treatment regardless of age, disability, neurodiversity, gender, gender identity, gender reassignment, marital or civil partner status, pregnancy or maternity, race, colour, nationality, ethnic or national origin, religion or belief, sex and sexual orientation. We welcome all applications for this role.

We are committed to providing reasonable support/adjustments in our recruiting processes. If you need support, please reach out to the hiring contact.

Please see our privacy notice: https://smartnumbers.com/privacy-notice/