Senior Engineer (frontend)

As a Senior Frontend Engineer at Sage, you will contribute and lead in the design, development, and delivery of features for a high-quality SaaS solution that exceeds customer and business partner expectations. You will work closely with product managers and designers and proactively share your own knowledge of frontend technologies and practices with the wider team. We are looking for someone with 7+ years of professional experience in frontend engineering. Proficiency in English, written and verbal, is required.

We value humility and collaboration. We are looking for people who can work as part of a team, not in silos. We expect engineers to take ownership beyond just writing code, including tests, documentation, and long-term code quality.

Location: Bangalore, India. This is a hybrid role, three days per week in the office.

Required Skills

• 7+ years of professional experience in software development for scalable, web-based applications.
• Proficiency in English, written and verbal, is required.

Core languages & frameworks

• Strong TypeScript (strict) and modern JavaScript (ES Modules, async).
• Deep React experience (hooks, composition, performance); React 19 / React Compiler a plus.
• Solid HTML5, CSS3, and responsive/accessible UI fundamentals.

Build & tooling

• Modern build tooling Vite (or Webpack/Rollup); code splitting and bundle optimization.
• Git and pull-request workflows; monorepo experience (Nx) a plus.
• Linters/formatters (Biome, ESLint/Prettier) and CI discipline.

State & data

• State management with Redux Toolkit, XState (state machines), and/or TanStack Query.
• RxJS / reactive streams.
• Consuming REST APIs; JWT/OAuth2 bearer auth on the client; robust error handling.

Styling & design systems

• Tailwind CSS, MUI (Material UI), styled-components/Emotion.
• Working with a design-token system for brand consistency.

Data grids & performance

• Complex data grids (ag-Grid Enterprise preferred, or TanStack Table/Handsontable): virtualization, server-side row model, custom renderers/editors.
• Frontend performance profiling and optimization (rendering, memoization, main-thread work).
• Web Workers for off-main-thread compute.

Accessibility & i18n

• WCAG 2.1/2.2 AA accessibility practices; ARIA, keyboard, focus management.
• Internationalization (i18next or similar), including locale-aware date/number formatting.

Testing & quality

• Unit/component testing (Vitest/Jest + Testing Library), API mocking (MSW), and Playwright E2E.
• Secure client-side coding against the OWASP Top 10 (XSS, token handling, safe storage).

AI Tooling

• Productive use of AI-assisted developer tooling (e.g. GitHub Copilot, Claude Code, Cursor) to accelerate day-to-day frontend development.
• Building AI-assisted / generative-AI UX: in-app copilots, natural-language querying, or smart suggestions surfaced to the user.
• Integrating LLM APIs on the client (e.g. OpenAI, Anthropic, AWS Bedrock) with streaming/token-by-token rendering, cancellation, and graceful error/loading states.

Soft skills

• Strong problem-solving abilities and an eagerness to learn.
• Excellent communication skills and the ability to work well in a team.
• High attention to detail and a commitment to delivering high-quality work.

Nice to Have

• Web Crypto / AES-GCM application-level encryption and client-side key management.
• Lexical (or ProseMirror/Slate) rich-text/formula editors; grammar parsing (ohm-js).
• Dependency-graph / DAG modeling (graphlib/graphology).
• CRDT / operational-transform real-time collaboration.
• Storybook and visual regression testing.
• New Relic browser RUM, Pendo, and web-vitals (INP/FPS) instrumentation.
• Experience meeting enforced performance budgets and SLOs in CI.
• Domain knowledge in finance, ERP, FP&A, budgeting, or spreadsheet-like applications.
• Designing accessible, trustworthy AI interaction patterns, such as citations, confidence indicators, and human-in-the-loop review for sensitive outputs.

Responsibilities

Responsibilities

• Collaborate with cross-functional teams to design, develop, and maintain new features for our SaaS platform, applying a broad knowledge of frontend principles and practices to difficult assignments.
• Write clean, maintainable, and well-documented code, and act as a source of technical guidance in code reviews and best-practice discussions.
• Mentor and coach junior members of the development team.
• Debug and resolve issues reported by users or identified in the production environment.
• Improve the performance, scalability, and security of the platform.
• Implement and maintain automated tests to ensure software reliability.
• Work closely with the design team to ensure the platform is user-friendly and follows UI/UX best practices.
• Partner effectively with product, design, and engineering peers to deliver assigned work.
• Stay up-to-date with the latest trends in web development and cloud-based SaaS technologies.