Sr. Frontend Engineer AI Platform

Who We Are

Addepar is a global technology and data company that helps investment professionals provide the most informed precise guidance for their clients. Hundreds of thousands of users have entrusted Addepar to empower smarter investment decisions and better advice over the last decade. With client presence in more than 50 countries Addepars platform aggregates portfolio market and client data for over $8 trillion in assets. Addepars open platform integrates with more than 100 software data and services partners to deliver a complete solution for a wide range of firms and use cases. Addepar embraces a global flexible workforce model with offices in New York City Salt Lake City London Edinburgh Pune Dubai Geneva andSão Paulo.

The Role

We are currently seeking a Senior Frontend Software Engineer to join the AI Platform team Addepars next-generation AI platform that enables seamless insights and interaction through natural language and data intelligence across our AI products.

As a Senior Frontend Engineer youll design and scale the interactive surface of AI Platform products. Youll work at the intersection of AI design and systems engineering building a class of real-time AI experiences for users where every frame token and scroll behavior matters.

You will collaborate closely with product design backend and AI/ML engineers to deliver smooth trustworthy AI experiences that align with Addepars standards of performance transparency and reliability.

What Youll Do

• Design and implement complex real-time UI features for conversational interfaces including chat streaming incremental rendering and dynamic layouts.
• Build high-performance WebSocket pipelines to handle streamed deltas retries and backpressure gracefully.
• Optimize scrolling and rendering performance using requestAnimationFrame virtualization intersection observers and non-blocking state updates.
• Implement fault-tolerant UI logic for reconnection cancellation offline recovery and retry without user disruption.
• Architect state management and caching strategies to maintain consistency between local UI and backend deltas.
• Collaborate with designers to deliver accessible responsive and pixel-perfect interfaces across themes and viewport sizes.
• Extend Addepars frontend developer experiencerefine the build pipeline (Vite/Webpack) test automation (Playwright Jest) and linting/formatting standards (ESLint Prettier).
• Instrument client-side telemetry and performance metrics to measure render latency streaming lag and user interaction speed.
• Mentor teammates through design reviews and pair programming contributing to shared components and cross-product standards.
• Work closely with backend and AI/ML teams to co-design message formats token streaming APIs and session-level resiliency mechanisms.
• Shape the technical direction of AI Platforms frontend contributing to shared libraries caching strategies.

Technical Fundamentals & Practices We Look For

Were looking for engineers who demonstrate mastery across the following practices and system fundamentals that empower to ship high-quality low-latency conversational experiences at scale:

1. Browser & Rendering Fundamentals

• Deep understanding of the browsers rendering pipelineDOM CSSOM layout paint compositing.
• Ability to identify and fix layout thrashing paint storms and jank through Chrome DevTools performance profiling.

Knowledge of animation scheduling via requestAnimationFrame idle callbacks and microtask with modern web APIs such as IntersectionObserver ResizeObserver MutationObserver OffscreenCanvas Web Workers and BroadcastChannel for concurrent or cross-tab coordination.

2. Asynchronous & Streaming Systems

• Strong command of Promises async/await generators and cancellation (AbortController).
• Familiarity with streaming data protocols (e.g. WebSockets SSE) and patterns like batching throttling and debounce under load.

Understanding of backpressure and how to pace UI rendering vs. message ingress.

3. State & Data Synchronization

• Experience designing immutable data flows with fine-grained updates (diffs patches deltas).
• Knowledge of caching reconciliation and hash-based change detection (e.g. djb2 CRC32 content hashing).

Practices for ensuring consistency between transient client state and authoritative backend models.

4. UI Architecture & Composition

• Familiarity with reactive component frameworks (Svelte preferred; React/Vue acceptable).
• Experience isolating side effects using stores/signals and maintaining predictable reactivity graphs.

Ability to decompose large applications into feature modules with lazy loading error boundaries and shared design tokens.

• Ability to evaluate and integrate across frameworks (Svelte React Web Components) while maintaining consistent patterns in state testing and accessibility.

5. Performance & Profiling

• Proven skill in measuring and optimizing UI latency (first paint input delay FPS stability).

Comfort with Chrome Performance Lighthouse or custom performance building virtualized views (infinite scroll chat lists large tables).

Systems & Accessibility

Experience building and maintaining reusable design systems with Storybook Tailwind or Web of accessibility standards (WCAG ARIA) and best practices for keyboard color and screen reader at collaborating with design teams to translate high-fidelity Figma specs into performant production-ready components.

7. Resilience Testing & Observability

• Writes defensive code to handle partial data dropped connections race conditions and AbortErrors.
• Understands test pyramids: unit integration and end-to-end (Playwright Jest Vitest).

Adds telemetry hooks and log events to diagnose production issues and user experience regressions.

8. Developer Experience & Tooling

• Comfortable configuring bundlers (Vite Webpack) and optimizing build times.
• Sets up linting type checking and pre-commit automation for consistency.
• Experience with CI/CD incremental testing and feature flag rollouts.
• Experience with AI-assisted developer tools or scripting build/test automation to improve team velocity.

• You think in systems not pages.
• You balance aesthetics with performance correctness and maintainability. You obsess over the invisible details micro-interactions latency and flow that make complex products feel effortless.
• You enjoy teaching others debugging difficult issues and making the team move faster through better abstractions.

Who You Are

• Bachelors degree in Computer Science Engineering or related technical field (or equivalent practical experience).
• Minimum 5 years of professional frontend development experience in a production environment.
• Strong proficiency in TypeScript/JavaScript and deep understanding of asynchronous browser behaviour.
• Experience with Svelte React or another component-based modern UI framework.
• Strong debugging and performance profiling skills.
• Experience integrating real-time or streaming data into user interfaces.
• Strong communication collaboration and mentoring skills.
• Additional certifications or licenses
• Skills and competencies that also include soft skills necessary for success
• Bonus: Familiarity with AI/LLM-powered interfaces progressive streaming UIs or data-rich visualization frameworks.

You care deeply about user experience developer productivity and measurable performance and you know that excellence in frontend engineering is achieved through curiosity rigor and empathy for both users and teammates.

Important Note: This role requires working from our Pune office 3 days a week (hybrid work model)

Our Values

• Act Like an Owner - Think and operate with intention purpose and care. Own outcomes.
• Build Together - Collaborate to unlock the best solutions. Deliver lasting value.
• Champion Our Clients - Exceed client expectations. Our clients success is our success.
• Drive Innovation - Be bold and unconstrained in problem solving. Transform the industry.
• Embrace Learning - Engage our community to broaden our perspective. Bring a growth mindset.

In addition to our core values Addepar is proud to be an equal opportunity employer. We seek to bring together diverse ideas experiences skill sets perspectives backgrounds and identities to drive innovative solutions. We commit to promoting a welcoming environment where inclusion and belonging are held as a shared responsibility.

We will ensure that individuals with disabilities are provided reasonable accommodation to participate in the job application or interview process to perform essential job functions and to receive other benefits and privileges of employment. Please contact us to request accommodation.

PHISHING SCAM WARNING: Addepar is among several companies recently made aware of a phishing scam involving con artists posing as hiring managers recruiting via email text and social media. The imposters are creating misleading email accounts conducting remote interviews and making fake job offers in order to collect personal and financial information from unsuspecting individuals. Please be aware that no job offers will be made from Addepar without a formal interview process. Additionally Addepar will not ask you to purchase equipment or supplies as part of your onboarding process. If you have any questions please reach out to .