--- title: 'Senior Machine Learning Engineer, Recommendation at Sekai' canonical: 'https://feeny.ai/job/senior-machine-learning-engineer-recommendation-sekai-san-francisco-14543wa39ct9' type: 'job' last_seen: '2026-10-29' --- # Senior Machine Learning Engineer, Recommendation at Sekai - **Company:** Sekai - **Location:** San Francisco, CA - **Employment:** full-time - **Work type:** remote - **Posted:** 2026-10-20 - **Last confirmed live:** 2026-10-29 - **Apply:** https://jobs.ashbyhq.com/sekai/512cc777-ad6b-4924-8fef-fa5325811483 ## Job description Sekai is building the TikTok for mini apps — an AI-driven consumer platform where people create, remix, share, and play interactive content instantly. We are a Series A company backed by Khosla, a16z and Mayfield, with $30M raised to date. We are remote-first across all positions and are looking for ambitious, AI-native builders who want to help shape the next generation of consumer social products. Download our app and give it a try! - Android: https://play.google.com/store/apps/details?id=chat.sekai.app&hl=en_US - iOS: https://apps.apple.com/us/app/sekai-create-remix-play/id6504506653 ## About the Role We are looking for a Senior Machine Learning Engineer to own search and recommendation systems for Sekai’s consumer product. This role sits at the center of content discovery, user engagement, and content distribution. You will build the models and systems that decide what users see, what they search for, what they continue playing, and how high-quality content reaches the right audience. This is a senior IC role for someone who has built real recommendation, search, ranking, or discovery systems in production for consumer apps, especially in entertainment-driven products. ## What You Will Own - Build and improve recommendation and search systems across feed, discovery, search, and content continuation surfaces. - Own retrieval and ranking systems, including candidate generation, embedding-based retrieval, two-tower models, ranking features, and online serving quality. - Design, launch, and analyze recommendation/search experiments end-to-end, then use the data to iterate quickly. - Improve recommendation quality for new users, new content, and fast-changing content pools. - Build user, content, creator, and session-level representations from behavioral signals. - Partner with product, data, and engineering teams to define metrics, run experiments, and ship measurable improvements to retention, engagement, and content distribution. - Build practical ML systems that can move from prototype to production quickly, with clear monitoring and evaluation. - Help shape the long-term ML architecture for AI-native content discovery. ## What We Are Looking For - 5+ years of industry experience building production ML systems, with senior-level ownership of recommendation, search, ranking, ads ranking, feed ranking, or content discovery systems. - Hands-on experience building recommendation or search systems for consumer apps. - Experience working on entertainment, social, gaming, short-form content, creator, or other engagement-driven consumer products. - Strong practical experience with two-tower models, embedding retrieval, candidate generation, ranking, and online/offline evaluation. - Strong product intuition around relevance, retention, engagement, satisfaction, cold start, and content distribution. - Ability to translate messy user behavior into useful modeling signals and practical product improvements. - Strong engineering fundamentals across modeling, data pipelines, backend integration, experimentation, and production ML systems. - High ownership, fast execution, and clear communication in ambiguous product environments. ## Nice to Have - Experience with AI recommendation, LLM-powered ranking, semantic search, personalized generation, or AI-native content understanding. - Experience with UGC content ecosystems, creator marketplaces, or rapidly changing content catalogs. - Experience with multimodal content understanding across text, image, video, interaction traces, or generated content. - Experience with explore/exploit, contextual bandits, reinforcement learning, or long-term value optimization. - Startup experience or experience building 0-to-1 ML systems with limited infrastructure. ## Benefits - Top compensation package, including competitive salary and meaningful equity. - Comprehensive health insurance and benefits. If you are excited about building at the frontier of AI, consumer social, and interactive entertainment, we would love to hear from you. At Sekai, you will work with an AI-native team, move fast, own meaningful problems, and have the flexibility to explore new ideas from an early stage. If you are excited about building at the frontier of AI, consumer social, and interactive entertainment, we would love to hear from you. At Sekai, you will work with an AI-native team, move fast, own meaningful problems, and have the flexibility to explore new ideas from an early stage. ## About Sekai ## Company Overview - **One-liner**: Sekai is an AI-native social platform that lets anyone create, play, and remix interactive mini-apps (called "Sekais") using text prompts, turning software into shareable cultural artifacts. - **Entity Type**: Private (Series A; raised $20M in June 2026) - **Headquarters**: Sunnyvale, California, United States - **Founded**: 2023 (incorporated as Versa AI, Inc.) - **Founders**: Lucky Zhang ## Core Business - **Primary industry/industries**: AI-powered social content / User-generated mini-apps / Generative interactivity - **Target customers**: B2C – consumers (especially younger demographics) who want to create, discover, and remix playful, utility, or fan-interaction mini-apps; also creators and potential celebrity partners. - **Mission or purpose statement**: To move beyond static content (text, image, video) and build the first ecosystem for "Generative Interactivity" – making software a medium for creative expression and social sharing. ## Products & Services - **[Sekai Platform (app + web)]**: An AI-driven platform (iOS, Android, and web) where users describe an idea in natural language and a mini-app is instantly generated. Apps can be utilities, quizzes, polls, cards, games, or fan experiences. Users can play, remix others' creations, and share them. Includes a creator monetization path (in development). **Type**: AI-powered SaaS / mobile app ## Market Standing - **Valuation/Market Cap**: Not publicly disclosed (private company). - **Key Metric**: Total funding – $26M ($20M Series A co-led by Khosla Ventures and Connect Ventures in June 2026, plus $6M seed led by Mayfield in 2025). Also received $3M in pre-seed/non-equity assistance in 2024. - **Notable Investors/Partners**: Khosla Ventures, Connect Ventures (joint CAA/NEA), a16z Speedrun, Mayfield, A*, MVP Ventures, 359 Capital, Parable VC, 645 Ventures. Early backing from a16z Games Speedrun. - **Growth Signals**: - 15 million mini-apps created, with over 200,000 generated daily. - Users spend more than 1 hour per day on the app. - 550% YoY headcount growth (from ~3 to 16 employees). - 4,689 LinkedIn followers (+611.5% yearly). - Active hiring: 7 open positions as of July 2026. ## Competitive Advantages - **First-mover in AI-native social app creation**: Unlike traditional social media, Sekai enables true interactive creation – not just content consumption. - **Remix culture + low barrier**: Users can create without coding; remixing others' apps lowers friction and drives viral loops. - **Strong engagement metrics**: >1 hour daily usage signals product-market fit and user “obsession” (per investor Nicole Quinn). - **Founder track record**: Lucky Zhang previously sold startups to Apple (Yi+ AI) and ByteDance (Blacktail), showing execution and exit experience. ## Strategic Focus - **Scaling the creator economy**: Sekai plans to help creators earn money from their mini-apps and interactive fan experiences. - **Expanding partnerships**: Working with CAA on creator and celebrity partnerships. - **Hiring aggressively** for engineering, product, and AI roles to build out the platform and mobile experience. - **Broadening beyond anime/fan-fiction** (initial niche) into general-purpose mini-app creation as AI coding models improve. ## Why Work Here - **Culture of creativity and impact**: Sekai describes itself as the “first AI-native social platform” – employees get to build a new medium, moving beyond doomscrolling to active creation and interaction. - **Early-stage growth**: Very small team (16 people) with massive funding ($26M) and explosive user traction – high ownership and ability to shape product. - **Founder with serial success**: Working under Lucky Zhang, who has sold two companies to Apple and ByteDance, provides credible leadership and deep AI/social experience. - **Remote/hybrid policy**: Likely flexible; job postings on Ashby (e.g., AI Product Engineer) include "Remote" tag. HQ is in Sunnyvale, CA, but team spans US, Indonesia, Singapore, NZ. - **Notable perks/engineering culture**: Focus on rapid prototyping, AI tools, and user-generated content. Roles posted include "AI Agent Engineer," "Senior Data Engineer," "AI Product Engineer" – strong AI engineering environment. ## Sources 1. [Sekai Official Website](https://sekaiapp.com/) 2. [Sekai LinkedIn Company Page](https://www.linkedin.com/company/sekaiapp) 3. [Axios – Sekai raises $20M (June 2026)](https://www.axios.com/2026/06/01/sekai-mini-app-startup-funding) 4. [Sekai Careers Page (Ashby)](https://jobs.ashbyhq.com/sekai) 5. [Google Play Store – Sekai App](https://play.google.com/store/apps/details?hl=en_US&id=chat.sekai.app) ## Other roles at Sekai - [AI Product Engineer](https://feeny.ai/job/ai-product-engineer-sekai-san-francisco-8w89jswmwt1r) — San Francisco, CA - [Senior Android Engineer](https://feeny.ai/job/senior-android-engineer-sekai-san-francisco-q9h3pwy2ymeq) — San Francisco, CA - [Founding iOS Engineer](https://feeny.ai/job/founding-ios-engineer-sekai-san-francisco-hey4az5dytnr) — San Francisco, CA - [Technical Lead](https://feeny.ai/job/technical-lead-sekai-san-francisco-1g5rmq77d78h) — San Francisco, CA - [AI Product Manager](https://feeny.ai/job/ai-product-manager-sekai-san-francisco-sktzt4dzx3vx) — San Francisco, CA - [AI Agent Engineer (Coding Agent)](https://feeny.ai/job/ai-agent-engineer-coding-agent-sekai-san-francisco-bamz39dkfd3v) — San Francisco, CA