Senior Frontend Engineer - SDE III at Certa · Remote only · 4 - 8 years · Raised funding · Remote only · Posted 4 May 2026

Certa (getcerta.com) is a Silicon Valley-based tech product start-up that is automating the vendor, supplier, and other stakeholder onboarding processes (think background checks, agreements, and the works) for companies across industries and geographies. With multiple Fortune 500 and Fortune 1000 clients, at Certa's tech team, you will be working on stuff that is changing the way huge companies do business.
Must Haves:
- Experience developing enterprise-grade quality software.
- 3+ years of experience building large-scale front-end applications using React.
- 3+ years of experience using type-safe JavaScript-based languages, such as TypeScript.
- Understanding of modern frontend ecosystems, including Bundling(preferably using vite) Linting, Testing, Releasing.
- Success with mentoring mid-level & junior Engineers.
- Experience in Agile software development methodologies.
- Experience writing automated tests (e.g., Vitetest, Cypress, Jest, Testing Library).
- Experience in building, scaling & maintaining a design system from scratch.
- Experience in improving rendering as well as delivery performance for front-end applications.
- Experience in writing semantic HTML.
- Experience in building scalable, responsive, and cross-browser-compatible web applications.
- Experience in a peak-performance organization, preferably a tech startup.
- Experience working with a remote team.
- Data analysis experience, and understanding of how analytics can help with product decisions.
Bonus:
- Experience building integrations and data synchronizations with event pub/sub-models.
- Experience with WebGL
- Experience in building offline applications using Web Workers
- Open source contributions.
- Running his/her own blog.
- Experience with building 100% keyboard and screen reader-accessible applications.
- Experience setting up and customizing JavaScript tooling and building systems.

About Certa
About
Certa’s no-code platform makes it easy to digitize and manage the lifecycle of all your suppliers, partners, and customers. With automated onboarding, contract lifecycle management, and ESG management, Certa eliminates the procurement bottleneck and allows companies to onboard third-parties 3x faster.
Tech stack
Connect with the team
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NEED TO HAVE :
1) Have some knowledge of front end like React.JS
2) HTML, CSS
3) Strong in JavaScript concepts
4) Good communication skills
5) Loves to code
GOOD TO HAVE :
1) Experience with type script will be a plus
2) Experience with Nest.JS framework will be a plus
3) Strong hold on ES6 principles.
4) Familiar with TDD ( Test Driven Development ) will be a plus.
5) Familiar with working in CI / CD will be a plus
6) Micro-Service architecture knowledge will be an added benefit.
You can contact me on this WhatsApp number: Nine three one six one two zero one three two
Role Summary
The Senior Front-end Developer builds and maintains client-facing interfaces per UI/UX designs and product requirements, owns front-end architecture and code-review standards, and mentors the Junior Front-end Developer. This is a specialized front-end role, not a full-stack position.
Key Responsibilities
• Own front-end architecture decisions, including framework, state management, and tooling choices.
• Set and enforce code-review, testing, and performance/accessibility standards for the pod.
• Lead implementation of complex, high-visibility features.
• Troubleshoot and resolve complex front-end performance or technical issues.
• Mentor the Junior Front-end Developer, including code review and skill development.
• Partner closely with UI/UX to ensure design fidelity and flag implementation constraints early.
• Evaluate and recommend front-end tooling or library upgrades.
Required Skills & Technical Competencies
• Deep expertise in a modern front-end framework (React strongly preferred) and associated ecosystem.
• Strong understanding of front-end performance optimization and accessibility standards.
• Experience owning front-end architecture for a production application.
Targeted Qualifications
• 5–8 years of front-end development experience.
• Deep expertise in a modern framework (React preferred) and front-end architecture patterns.
• Experience owning performance and accessibility standards.
• Bachelor's degree in Computer Science or related field.
Preferred / Nice-to-Have
• Experience with data-dense or real-time dashboard interfaces (relevant to IoT products).
• Experience mentoring junior developers formally.
The recruiter has not been active on this job recently. You may apply but please expect a delayed response.
We are seeking an experienced, hands-on SDE 3 - FE to build and optimize scalable, user-friendly applications with a focus on micro frontend architectures. The ideal candidate will blend strong UI engineering skills with modern frontend practices, ensuring responsive, secure, and high-quality experiences aligned with business needs.
Responsibilities
● Design & Build: Develop scalable, performant front-end applications using React, TypeScript, and Micro Frontend architecture.
● Code Quality: Review PRs, enforce best practices, and introduce patterns to reduce technical debt.
● UI/UX Excellence: Deliver pixel-perfect, responsive, and accessible UIs across devices and browsers.
● Performance: Optimise rendering, bundling, caching, and load times for smooth user experiences.
● Mentorship: Guide and mentor mid/junior engineers, run design/code walkthroughs, and foster a culture of technical excellence.
● AI-driven Development: Leverage AI tools to accelerate coding, debugging, testing, and documentation in day-to-day workflows.
Criteria:
Experience: ~5–7+ years in software development, with proven expertise in React, modern frontend architectures, and building scalable user interfaces.
Technical Skills
● Strong proficiency in React.js (v17+), TypeScript, and modern frontend workflows.
● Experience with Micro Frontend architectures (e.g., Module Federation, Webpack, or similar approaches).
● Solid expertise in HTML5, CSS3, and mandatory proficiency with Bootstrap for responsive design.
● Knowledge of Blade templates for frontend-backend integration.
● Good-to-have: Tailwind CSS and Material UI for component-based design systems.
● Deep understanding of state management (Redux, Recoil, or equivalent).
● Experience with frontend performance optimisation and browser dev tools.
● Familiar with testing frameworks (Jest, React Testing Library, Cypress).
● Proficiency with Docker and containerised environments.
● Experience with CI/CD pipelines for frontend deployments.
● Ability to effectively use AI-powered tools for code generation, refactoring, documentation, and productivity improvements.
Soft Skills
● Clear and effective communication.
● Strong sense of ownership and accountability.
● Ability to break down complex problems and provide accurate estimates.
● Openness to adopt new tools/technologies to improve team efficiency.
What we offer:
● An exceptional team: Our hiring bar is high, and your colleagues are talented, motivated self-starters.
● A learning environment: We are a learning organisation, and as a team, we will help you grow and encourage you to learn and upgrade your skills.
● Outstanding compensation: top talent deserves top pay, and our salary, equity and benefits reflect this.
● Opportunities to grow: Encourages you to attend technical conferences and take company funded educational courses to advance your skills.
● An opportunity to be a key member of a well-capitalised, leading brand in an online real estate investing platform.
This role is for our client, who are reimagining video security for the modern world. Their cloud-native platform uses computer vision and AI to help businesses stay safe, make smarter decisions, and move faster; from real-time alerts to seamless clip sharing and multi-site visibility.
You’ll be joining an ambitious, fast-moving team that values clarity, craftsmanship, and impact. Every person there has a voice, ships meaningful work, and helps shape how AI can make the world safer and more connected.
Responsibilities
- Architect and scale high-performance React and TypeScript applications built for real-time surveillance operations.
- Build UI components for video playback, timeline scrubbing, and multi-camera grid management.
- Optimize client-side rendering, network bandwidth, and browser memory usage when streaming high-frequency data.
- Partner closely with Product, Design, and Machine Learning engineers to transform complex AI detection capabilities into simple user experiences.
- Establish frontend architecture patterns, maintain testing standards, and mentor team members.
Skills And Qualifications
- Experience building production web applications in React and TypeScript
- Deep understanding of frontend performance profiling, browser memory management, and client-side optimization
- Hands-on experience working with real-time data streams (WebSockets, SSE, or WebRTC)
- Strong software engineering fundamentals, including modular architecture, state management, and automated testing
- High bar for UI detail, usability, and web accessibility is a plus
- Experience with video technologies on the web (HLS, WebRTC, MSE, or Canvas/WebGL video rendering) is a plus
- Experience building spatial or location-aware dashboards using mapping tools (e.g., Mapbox, Leaflet) is a plus
- Prior experience in fast-paced startup environments or developer-centric B2B SaaS platforms is a plus
What We Offer
- Competitive compensation package
- Early-stage equity in a rapidly growing company
- Referral bonuses
- Team dinners and regular team off-sites
- The latest Apple products and unlimited tech stack
The company is on a mission to transform a $50B+ legacy industry by bringing the power of cutting-edge multimodal LLMs and computer vision to real-world security and operations. From firearm detection to intelligent access control, our AI-native platform turns every camera and sensor into a smart system that enhances safety, efficiency, and awareness.
Job Description:
https://drive.google.com/file/d/12Fcie5u0rhyHeE_xhsNTeGk3mlPId1Mb/view?usp=drive_link
About NonStop io Technologies:
NonStop io Technologies is a value-driven company with a strong focus on process-oriented software engineering. We specialize in Product Development and have a decade's worth of experience in building web and mobile applications across various domains. NonStop io Technologies follows core principles that guide its operations and believes in staying invested in a product's vision for the long term. We are a small but proud
group of individuals who believe in the 'givers gain' philosophy and strive to provide value in order to seek value. We are committed to and specialize in building cutting-edge technology products and serving as trusted technology partners for startups and enterprises. We pride ourselves on fostering innovation, learning, and community engagement. Join us to work on impactful projects in a collaborative and vibrant environment
Brief Description:
NonStop io is seeking a proficient React.js developer to join our front-end development team. In this position, you’ll be mainly crafting and integrating UI components through React.js methodologies and workflows like Mobx and Redux.
Responsibilities:
● Developing and implementing UI components using React.js
● Collaborating with cross-functional teams to design and ship new features
● Building reusable components and front-end libraries for future use
● Translating designs and wireframes into high-quality code
● Optimizing components for maximum performance across various web browsers
● Troubleshooting and debugging issues to ensure smooth user experiences
● Participating in code reviews to maintain code quality and consistency
● Improvement and optimization of existing codebase
● Keeping up with industry trends
● Identifying issues with technologies and architecture and then implementing solutions
● Assist with ticket creation, refinement, and estimation
● Participate in sprint planning and ticket distribution for frontend team
Qualifications & Skills:
● Proficiency in React.js and its core principles
● Strong JavaScript, TypeScript, HTML5, and CSS3 skills
● Experience with popular React.js state management libraries and approaches (such as Mobx, Redux, and Context API)
● Familiarity with RESTful APIs and integration
● Knowledge of modern authorization mechanisms, such as JSON Web Tokens
● Understanding of front-end build tools and pipelines
● Familiarity with any one of backend technologies such as Node.js, Java, or Python
● Excellent problem-solving and communication skills
● A strong attention to detail, and a passion for delivering high-quality code
● Expertise in designing scalable and efficient front-end architecture
● Adaptability to changing project requirements and priorities
● Experience with version control systems, particularly Git
● Experience working in Scrum and familiarity with Atlassian (Jira, Confluence, Bitbucket)
● Experience with diverse applications and architectural patterns
● A degree in computer science, software engineering, or a related field
● Strong understanding of object-oriented programming principles and design patterns
● Familiarity with automated testing frameworks and methodologies
● Excellent problem-solving skills and attention to detail
● Strong communication skills and ability to work effectively in a collaborative team environment
● Ready to be a tech-agnostic engineer and comfortable to shift on any tech stack
● Comfortable working with AI (Claude code, Cursor etc)
If you're passionate about technology and want to work on impactful projects, we'd love to hear from you
Job Summary
We are looking for an experienced Frontend Developer / Angular Developer with 5+ years of hands-on experience in building responsive, scalable, and high-performance web applications. The ideal candidate should have strong expertise in Angular, TypeScript, JavaScript, HTML, CSS, along with a good understanding of Java-based backend applications and REST APIs.
Key Responsibilities
- Design, develop, and maintain responsive web applications using Angular.
- Build reusable, scalable, and maintainable UI components.
- Develop clean and efficient code using TypeScript, JavaScript, HTML5, and CSS3.
- Integrate frontend applications with RESTful APIs and Java-based backend services.
- Collaborate with backend developers, UI/UX designers, QA engineers, and business teams.
- Troubleshoot, debug, and optimize application performance.
- Implement responsive designs and ensure cross-browser compatibility.
- Participate in code reviews and follow coding and development best practices.
- Write unit tests and support integration and system testing.
- Analyze production issues and provide effective technical solutions.
- Contribute to application architecture and technical design discussions.
Required Skills
- 5+ years of professional software development experience.
- Strong hands-on experience with Angular.
- Strong knowledge of TypeScript and JavaScript.
- Good understanding of HTML5, CSS3, and responsive web development.
- Experience with Angular components, services, directives, routing, forms, RxJS, and state management.
- Experience integrating REST APIs.
- Good understanding of Java / Spring Boot and backend application integration.
- Knowledge of Git and standard software development practices.
- Experience with debugging, performance optimization, and browser developer tools.
- Good understanding of Agile/Scrum development methodologies.
Good to Have
- Experience with Angular Material or other UI frameworks.
- Knowledge of Java, Spring Boot, Microservices, and SQL.
- Experience with Jasmine/Karma or Jest.
- Exposure to CI/CD pipelines and cloud platforms.
- Knowledge of application security and frontend performance optimization.
Key Responsibilities
Frontend & Extension Development
• Build and maintain highly responsive, modern user interfaces using React.js for web applications, browser extensions, and Electron-based desktop clients.
• Architect and develop modular, reusable UI components using Material-UI (MUI / Joy UI) and styled-components/Emotion.
• Manage complex multi-target build pipelines (Web, Extension, Electron) using Webpack and Craco.
AI Integration & Engineering
• Seamlessly integrate Generative AI capabilities into the frontend, including AI-driven chatbots, contextual AI suggestions, and RAG (Retrieval-Augmented Generation) interfaces.
• Collaborate closely with backend and AI specialists to consume AI-powered REST APIs and WebSocket streams, ensuring fluid and responsive user experiences.
• Implement robust markdown and code rendering (e.g., react-markdown) for rich AI conversational outputs.
Real-Time Data & State Management
• Implement low-latency, real-time communication features using Socket.IO for chat and collaborative functions.
• Efficiently manage complex application state, data fetching, and caching using modern tools like React Query and Axios.
Quality & Collaboration
• Work within a monorepo/workspace structure to maintain distinct client, component, and extension packages.
• Participate in code reviews to maintain high code quality, performance, and enterprise security standards.
• Collaborate with teams using Agile/Scrum methodologies for rapid and structured delivery.
Required Skills:
• Core Languages: Proficiency in JavaScript (ES6+) and TypeScript.
• Frontend Frameworks: Strong, hands-on experience with React.js (Hooks, Context), React Query, and React Router.
• Styling & UI: Deep understanding of HTML5, CSS3, and CSS-in-JS libraries (e.g., styled-components, react-jss). Hands-on experience with MUI (Material UI / Joy UI) is highly preferred.
• Architecture & Build: Experience configuring and optimizing builds with Webpack and Craco. Familiarity with npm workspaces/monorepos.
• Real-time & APIs: Ability to design and implement robust client-side integrations with RESTful APIs and WebSockets (Socket.IO).
• Agile & Workflow: Experience working with Agile and Scrum methodologies.
Preferred/Bonus Skills:
• Experience in building and packaging Browser Extensions and/or Electron applications.
• Genuine curiosity and awareness of Generative AI workflows (e.g., prompt engineering concepts, handling streaming AI responses).
• Experience with rich text editing or markdown rendering in React.
Frontend Developers
- Contract To Hire (Initial Engagement: 6 months)
Experience: 5+ years
Mandatory Skills:
● React.js
● React Native
● JavaScript
● Experience in developing scalable and maintainable web and mobile applications
● Frontend architecture and reusable components
● State management
● REST API/backend service integration
● Application performance optimisation
● Authentication/authorisation and frontend security
● Git and pull-request-based development
● Clean, reusable and testable code
● Agile/product development experience
● Code reviews, debugging and production issue resolution
Good to have:
● TypeScript
● Next.js
● Jest / React Testing Library
● CI/CD
● Application monitoring
● Mobile deployment
The web is about to gain a second interface
Today, websites are designed for people. Agents must interpret pages, hunt for controls, and imitate clicks to accomplish anything.
We believe that will change. Websites will expose their capabilities directly to agents: structured, testable interfaces that work alongside the human experience. WebMCP is an early step toward that future. Signett is building the developer platform around it.
Our goal is to make creating an excellent agent interface as normal as building an API or testing a user interface.
The foundational product already exists. Signett has a public TypeScript library, documentation, benchmarks, real-world integrations, a website, and a Chrome extension. You would not be joining to turn a slide deck into an MVP. You would be joining to discover what makes a promising product become something developers genuinely adopt.
See it at signett.ai.
The opportunity
You would be Signett’s first hire and would have unusual ownership over the product’s direction.
Your job is to run one loop repeatedly:
- Find an external developer or team with a real reason to make its website agent-ready.
- Work inside its codebase and ship the integration.
- Identify what made the process difficult.
- Fix that friction yourself—in the library, documentation, testing tools, or extension.
- Publish what you learned so the next integration becomes easier.
You will move between engineering, product discovery, developer experience, and early distribution. There will be no handoff between those functions because, initially, you are the person connecting them.
The work could help establish how developers build and test agent interfaces for the web. It could also reveal that our present assumptions are wrong. Either outcome requires someone who cares more about finding the truth than defending the existing product.
The first 90 days
The initial targets are deliberately concrete:
- Five external teams attempt the 30-minute integration.
- At least three ship a real workflow without founder intervention.
- Two remain active or request a paid capability such as shared history, CI, analytics, or evaluations.
- Two reference integrations and case studies become public.
By the end, we should know which part of Signett developers truly value—exposure, testing, reliable execution, the Inspector, evaluations, or something we have not yet recognized.
You may be a strong fit if you have
- Six to ten years of experience as a product-oriented full-stack or frontend engineer.
- Strong TypeScript, React or Next.js, browser API, and Playwright or Cypress experience.
- Built SDKs, developer tools, browser tooling, API infrastructure, or observability products.
- Personally helped developers adopt something through documentation, examples, workshops, open-source work, or direct integrations.
- Enough commercial instinct to find a design partner, lead the conversation, and turn the resulting work into a useful public case study.
- The judgment and autonomy to make progress without daily direction.
- Clear writing and demonstration skills in addition to strong engineering ability.
Experience with WebMCP or MCP is helpful but not required. Curiosity and the ability to learn an evolving standard matter more. The WebMCP proposal is public at github.com/webmachinelearning/webmcp.
The anti-sell
Signett has a product, but it does not yet have proven product-market fit. Adoption is the open question, and answering it is the core of this role.
You should not join if:
- You want a role devoted entirely to writing code handed to you through a roadmap.
- You expect someone else to find users, conduct interviews, write documentation, or publish the work.
- You need a large team, established processes, or daily management to be effective.
- Your experience is primarily managing mature organizations rather than building from ambiguity.
- Your main strength is developer content without production software behind it.
- You want to research or train models rather than build browser-based products developers use.
- The uncertainty of an emerging standard makes you uncomfortable.
- You need the stability and specialization of a conventional engineering position.
.
This is not a comfortable job with a “founding” title attached to it. It is a chance to take a technically serious, public product and prove—or disprove—that it deserves to become an important company.
How we will start
We begin with a paid four-to-six-week project involving a real external TypeScript application, not a synthetic coding exercise.
The purpose is for both sides to experience the actual work: finding a useful integration, shipping it, learning from developers, and improving Signett. If the collaboration works and the evidence supports continued investment, the intended path is a permanent, full-time role.
The work is fully remote. Compensation, location, time-zone overlap, and the terms of the initial project will be discussed transparently before the process begins.






