Senior Frontend Engineer — Flow Builder & Editor

Adapty.io; Greater London; Hybrid; GBP 90,000 - 150,000; Full time

Benefits offered by this job

Flexible remote work

London office

Belgrade office

Language learning

Health insurance

Laptop coverage

Job summary

Adapty is looking for a Senior Frontend Engineer to own the frontend of Flow Builder. You will shape architecture, collaborate with product and design, and ensure fast, scalable editor performance across multiple runtimes.

You’ll work on an editor-like product with a document model, AI-driven features, and cross-platform rendering. The role offers flexible remote work with onsite options in London or Belgrade.

Qualifications

• 5+ years shipping production web applications in React and TypeScript.
• Editor-class interfaces: canvas, drag and drop, node or graph editors, WYSIWYG, design tools.
• Think in product terms: articulate problems solved and impact.
• Owned architecture on a product that keeps growing and boundaries you drew.

Responsibilities

• Take features from a customer problem to production: decide with product and design what to build, defend the call, ship it, and check what changed after release.
• Own the architecture of the editor and move it forward as the product grows: module boundaries, document model shape, reusable components, keep editor fast as flows scale.
• Ship across the editor surface: canvas and layers, element inspector, selectable groups and states, navigation, actions, variables, and conditional logic.
• Own the layer that translates editor config into SDK execution on device; negotiate the five-runtime contract with mobile team.
• Close the gap between browser preview and device rendering across layout, typography, media, dark mode, screen sizes, and orientations.
• Build the document model underneath all: nested configs, undo/redo, autosave, drafts vs published, and concurrent editing.
• Build the product around the AI Editor so generated screens are inspectable and reversible: prompt history, per-prompt undo, and a clear view of changes.

Skills

React

TypeScript

Frontend Architecture

Editor UI

Performance

Job description

Adapty is looking for a Senior Frontend Engineer to own the frontend of Flow Builder. You will shape architecture, collaborate with product and design, and ensure fast, scalable editor performance across multiple runtimes.

You’ll work on an editor-like product with a document model, AI-driven features, and cross-platform rendering. The role offers flexible remote work with onsite options in London or Belgrade.