Senior Backend Engineer

Seamless; Greater London; Hybrid; GBP 120,000 - 180,000; Full time

Job summary

Seamlessly is seeking a senior backend engineer to own server-side foundations, design scalable APIs, and integrate with the Salesforce platform at enterprise scale.

You will build AI workflows to convert unstructured inputs into structured CRM data, ensure performance, security, and reliability, and help shape the architecture as Seamlessly grows.

This role requires 10+ years of production experience with TypeScript backends and a passion for shipping high-quality, boringly reliable software.

Qualifications

• 10+ years of engineering experience, senior production experience on TypeScript backends.
• Strong API design instincts and a track record of integrations that scale.
• Salesforce platform experience (Apex, SOQL, REST APIs, custom metadata).
• An eye for security and data handling at enterprise standards.

Responsibilities

• Design and build scalable backend services that power our mobile apps.
• Integrate deeply with the Salesforce platform to read, write, and reflect customer metadata at enterprise scale.
• Build AI workflows that extract structured data from unstructured input.
• Own performance, reliability, and security across the full backend.
• Shape the architecture as Seamlessly grows.

Skills

10+ years engineering experience

API design

Salesforce integration

Security best practices

Tools

Apex

SOQL

REST APIs

TypeScript

Job description

Own the server-side foundations of Seamlessly. You will design and build the APIs, integrations, and AI workflows that turn every voice note and business card into structured CRM data. This is a senior role: we expect 10+ years of professional engineering experience.

What you will do

• Design and build scalable backend services that power our mobile apps.
• Integrate deeply with the Salesforce platform to read, write, and reflect customer metadata at enterprise scale.
• Build AI workflows that extract structured data from unstructured input.
• Own performance, reliability, and security across the full backend.
• Shape the architecture as Seamlessly grows.

What you will bring

• 10+ years of engineering experience, with senior production experience on TypeScript backends.
• Strong API design instincts and a track record of integrations that hold up at scale.
• Salesforce platform experience (Apex, SOQL, REST APIs, custom metadata).
• An eye for security and data handling at enterprise standards.

Nice to have

• Salesforce ISV or AppExchange experience.
• Serverless or event-driven backend experience.
• AI and LLM integration experience.

Who fits

You care about the things nobody sees until they break. You have opinions about API contracts, and you are usually right. You notice the field that was never validated, the query that will not scale to a hundred thousand orgs and the token that lives a minute too long, and none of it lets you rest until it is fixed. You treat customer data as if it were your own, because to the customer it is. You enjoy building new services, and you take the same pride in keeping the existing ones fast, safe and boring. You ship every week.