Member of Technical Staff - RL Training Framework

🏢 Summary: Role focused on post-training and reinforcement learning challenges for AI systems, including reward modeling, RLHF/DPO, and improving reasoning and truthfulness in models. The position involves hands-on work in a small engineering-driven team with high expectations for initiative, communication, and technical excellence. Compensation includes salary, equity, and comprehensive benefits. 🗂️ Requirements: Interest in truth-seeking AI, Experience or strong interest in post-training and reinforcement learning, Ability to build useful AI models with RL techniques, Strong understanding of RLHF or alignment methods, Hands-on engineering mindset, Strong communication skills, Ability to work in meritocratic, fast-paced environments 📃 Skills: Python, RLHF, DPO, Reinforcement, Alignment, Modeling, Post-training 🏢 Description: SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. The team is small, highly motivated, and focused on engineering excellence. Employees are expected to be hands-on, contribute directly to the mission, show initiative, and communicate clearly with teammates. ABOUT THE ROLE: You will work on critical post-training and reinforcement learning challenges, including reward modeling, preference optimization (RLHF/DPO), and reinforcement learning for improving reasoning, truthfulness, and real-world capabilities. You will get clarity on your first project before an offer. BASIC QUALIFICATIONS: - Believe truth-seeking AI is an important and challenging problem - Passion for building useful models through post-training and RL techniques - Strong interest in reinforcement learning and alignment methods - Experience with post-training, RLHF, or large-scale model training is a plus - Strong work ethic and prioritization skills - Strong communication skills - Ability to thrive in meritocratic environments COMPENSATION AND BENEFITS: - $180,000 - $600,000 USD - Equity package - Medical, vision, and dental coverage - 401(k) retirement plan - Short and long-term disability insurance - Life insurance - Additional discounts and perks SpaceXAI is an equal opportunity employer.

🏢 Summary: Applied Engineer role focused on building and scaling recommendation systems, ranking algorithms, and AI-driven search technologies for products serving hundreds of millions of users. The position involves developing machine learning infrastructure, real-time experimentation, and large-scale deep learning applications using modern AI frameworks and data systems. 🗂️ Requirements: Knowledge of Kafka, Clickhouse, and Spark, Experience implementing recommender systems at industrial scale, Experience with deep learning applications at industrial scale, Proficiency in JAX or PyTorch, Ability to design scalable machine learning systems, Strong communication skills, Hands-on engineering approach 📃 Skills: Kafka, Clickhouse, Spark, JAX, PyTorch, CUDA, Python, AI, ML 🏢 Description: SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company's mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. ABOUT THE ROLE: We're seeking exceptional Applied engineers to join a high-priority project that approximately 600 million monthly users use. This is an exciting opportunity for individuals with an engineer or scientist background to apply their skills to recommendation systems, ranking algorithms, search technologies, and many other systems. You'll work at the intersection of advanced AI development and real-world impact, enhancing the ability to connect users with relevant content, accounts, and experiences. RESPONSIBILITIES: - Designing and architecting recommendation algorithms across various product surfaces - Leverage all of xAI's infra and AI stacks to dramatically enhance the user experience - Write data pipelines and training jobs that continuously learn from product data - Iterate and improve the algorithm by gathering user feedback in real time through experimentation - Ensuring scalability and efficiency of machine learning systems BASIC QUALIFICATIONS: - Knowledge of data infrastructure like Kafka, Clickhouse, and Spark - Experienced in implementing recommender systems and/or deep learning applications at industrial scale - Skilled in one or more DL software frameworks such as JAX or PyTorch - Exceptional candidates may be experienced in writing CUDA kernels COMPENSATION AND BENEFITS: - $180,000 - $440,000 USD - Base salary is one part of the total rewards package and includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short and long-term disability insurance, life insurance, and additional discounts and perks. SpaceXAI is an equal opportunity employer. For details on data processing, view the Recruitment Privacy Notice.

🏢 Summary: Software Engineer role focused on building scalable data platforms and pipelines for AI model training, including data acquisition, preparation, orchestration, monitoring, and quality evaluation. The position involves collaborating with ML and data teams to develop reliable systems that support large-scale training workflows and improve model performance. 🗂️ Requirements: Bachelor's degree in Computer Science, Data Science, Engineering, Math, Physics, or related field OR 2+ years of professional software experience, 1+ years of experience in software engineering, application development, data engineering, or data science, Experience with programming languages such as Python, Rust, Java, C#, Scala, or Go, Experience with frontend frameworks such as Angular or React, Hands-on experience with Kubernetes and containerized deployments, Experience with relational and non-relational databases, Understanding of version control, testing, CI/CD, deployment, and monitoring, Understanding of statistics and machine learning frameworks 📃 Skills: Python, Rust, Java, C#, Scala, Go, Angular, React, Kubernetes, Ray, PostgreSQL, Iceberg, Clickhouse, Grafana, Superset, CI/CD, Docker, SQL, MachineLearning 🏢 Description: ABOUT THE ROLE: At xAI, we are building AI systems that push the frontier of human knowledge and scientific discovery. High-quality data is fundamental to every stage of that mission. Our Data team is responsible for ensuring that the models are trained on the right data, in the right form, at the right quality, across every phase of the training lifecycle. This includes partnering closely with acquisition teams to identify where valuable data can be sourced, determining what data is needed to improve model performance, and building the production pipelines and systems that transform raw inputs into high-quality training data at scale. We work at the intersection of software, data, infrastructure, and machine learning to ensure our models train effectively and reliably. As a Software Engineer on xAI's Data team, you will be responsible for developing applications that power data acquisition, preparation, training, quality evaluation, and delivery for model training. You will provide the ability to run training in a reliable, scalable and repeatable manner. You will also provide visibility on training status and data lineage. You will work closely with acquisition teams, ML engineers, and data engineers to build a reliable data pipeline to run training at scale. The ideal candidate combines strong software engineering fundamentals and excellent coding practices. RESPONSIBILITIES: - Develop a highly reliable and scalable enterprise data platform to orchestrate data acquisition, preparation, training, quality evaluation, and delivery for model training - Create new features such as data lineage, visibility, and monitoring for end-to-end training that improve the quality of the data and model performance - Collaborate with peers on architecture, design, and code reviews - Build prototypes to prove out key design concepts and quantify technical constraints - Own all aspects of software engineering and product development - Deep dive into business problems, find efficient solutions and apply first principles thinking BASIC QUALIFICATIONS: - Bachelor's degree in computer science, data science, engineering, math, physics, or scientific discipline; OR 2+ years of professional experience building software in lieu of a degree - 1+ years of experience in application development, software engineering, data engineering, or data science PREFERRED SKILLS AND EXPERIENCE: - Programming experience in Python, Rust, Java, C#, Scala, Go or similar languages - Frontend experience in Angular, React, or similar JavaScript frameworks - Hands-on experience with Kubernetes and containerized deployments - Experience with Ray, AI training and orchestration - Experience with relational and non-relational databases, data lakes e.g. PostgreSQL, Iceberg, Clickhouse, or similar - Experience with data exploration tools like Grafana, Superset, or similar - Good understanding of version control, testing, continuous integration, build, deployment and monitoring - Good understanding of statistics, machine learning algorithms and frameworks COMPENSATION AND BENEFITS: - $150,000 - $250,000 USD - Base salary is part of a total rewards package that includes equity, medical, vision, and dental coverage, 401(k) retirement plan, disability insurance, life insurance, and additional perks.

🏢 Summary: Software Engineer role focused on building and scaling a high-volume consumer platform with end-to-end ownership across frontend, backend, infrastructure, and AI integrations. The position involves developing distributed systems, microservices, analytics, and real-time features for products used by hundreds of millions of users. Candidates should have experience with large-scale applications, low-latency systems, and modern backend technologies. 🗂️ Requirements: 2+ years experience with large-scale consumer applications, Proficiency in distributed systems, Experience with high-scale low-latency environments, Experience with backend services and APIs, Experience with high-volume streaming systems, Strong communication skills, Ability to work in high-concurrency environments 📃 Skills: Rust, Go, Python, Java, APIs, Microservices, iOS, Android, Web, AI, Streaming, Analytics 🏢 Description: SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company's mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. ABOUT THE ROLE: As a Software Engineer for X Product/Platform, you'll join the thirty person team responsible for building and scaling X. You will be tasked with independently owning significant parts of the system end-to-end: from intuitive user interfaces to robust backend services, data infrastructure, and deep AI integrations. This is a unique opportunity to impact while creating products that are loved by 600M+ users globally. RESPONSIBILITIES: - Develop backend services, APIs, and data models to support high-volume, multi-user environments. - Work with iOS, Android & Web client engineers to ship products. - Design robust infrastructure and microservices for payments, transactions, growth, monetization, and engagement across platforms. - Build and maintain fullstack features, including user dashboards, personalized experiences, content delivery, interactive tools, assessments, and real-time analytics. - Lead architecture, scalability, and reliability decisions for high-concurrency, low-latency systems. - Uphold engineering excellence via testing, monitoring, deployment, and secure data handling. BASIC QUALIFICATIONS: - Proficiency in distributed systems for high-scale, low-latency environments; languages like Rust, Go, Python & Java, and high volume streaming systems. - 2+ years of experience working on large scale consumer applications. PREFERRED SKILLS AND EXPERIENCE: - 5+ years of experience working on large scale consumer applications or early-mid stage startup experience as a founding engineer, emphasizing rapid prototyping, user-centric design, and AI solutions. COMPENSATION AND BENEFITS: - $180,000 - $440,000 USD - Base salary is just one part of the total rewards package, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks. SpaceXAI is an equal opportunity employer. For details on data processing, view the Recruitment Privacy Notice.

🏢 Summary: AI engineering role focused on scaling synthetic training data, optimizing large-model training pipelines, and developing evaluation systems for advanced ML models. The position involves large-scale data processing, model distillation, and long-context data engineering in a highly technical environment. 🗂️ Requirements: Expertise in machine learning and large model scaling, Knowledge of scaling laws, Ability to design ML experiments, Experience with AI training data curation, Familiarity with text, image, audio, and video modalities, Strong engineering skills in large-scale data processing frameworks, Experience with Spark, Experience with Ray, Strong communication skills 📃 Skills: ML, Spark, Ray, Docker, RL, AI 🏢 Description: SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company's mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. RESPONSIBILITIES: - Scale synthetic coding data to trillions of tokens with large-scale docker verification. - Distill the intelligence of flagship models into flash models through synthetic data generation. - Optimize mid-training data mixtures to boost the ceiling for RL. - Engineer long-context data recipes. - Develop robust and diverse evaluation for mid-training checkpoints. BASIC QUALIFICATIONS: - Expertise in ML and large model scaling, with familiarity across all kinds of scaling laws. - Strong ability to design ML experiments. - Familiarity with state-of-the-art techniques for curating AI training data for text, image, audio, and video modalities. - Strong engineering abilities in Spark, Ray, and other frameworks for large-scale data processing. COMPENSATION AND BENEFITS: - $180,000 - $440,000 USD - Base salary is part of a total rewards package that includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and additional discounts and perks. SpaceXAI is an equal opportunity employer. For details on data processing, view the Recruitment Privacy Notice.

🏢 Summary: Role focused on solving critical AI modeling challenges within a hands-on, high-performance environment centered on building highly useful truth-seeking AI systems. Candidates are expected to contribute directly, communicate effectively, and thrive in a meritocratic culture with strong ownership and prioritization. 🗂️ Requirements: Belief in truth-seeking AI systems, Experience as a power user of AI models, Strong communication skills, Hands-on contribution mindset, Strong prioritization skills, Ability to thrive in meritocratic environments, Focus on building useful AI models 📃 Skills: AI, Modeling 🏢 Description: SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company's mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. ABOUT THE ROLE: You will work on the most critical modeling challenges at any given time. You will get clarity on your first project before an offer. BASIC QUALIFICATIONS: You believe truth-seeking AI is the most important and challenging problem. You are obsessed about building incredibly useful models. You are a power user of AI models. If you previously trained models used by millions of people it's a big plus, but modeling experience is not required. You take pride in your work and thrive in meritocratic environments. COMPENSATION AND BENEFITS: $180,000 - $600,000 USD Base salary is just one part of our total rewards package, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks. Equal opportunity employer. For details on data processing, view the Recruitment Privacy Notice.

🏢 Summary: Role focused on solving critical AI modeling challenges in a hands-on, high-performance environment with strong emphasis on useful AI systems and engineering excellence. Candidates will work on impactful projects with clarity on initial responsibilities before receiving an offer. The position offers high compensation, equity, and comprehensive benefits. 🗂️ Requirements: Belief in truth-seeking AI systems, Experience as a power user of AI models, Strong communication skills, Hands-on engineering mindset, Ability to thrive in meritocratic environments, Strong work ethic, Strong prioritization skills 📃 Skills: AI, Modeling, Engineering 🏢 Description: SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company's mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. ABOUT THE ROLE: You will work on the most critical modeling challenges at any given time. You will get clarity on your first project before an offer. BASIC QUALIFICATIONS: You believe truth-seeking AI is the most important and challenging problem. You are obsessed about building incredibly useful models. You are a power user of AI models. If you previously trained models used by millions of people it's a big plus, but modeling experience is not required. You take pride in your work and thrive in meritocratic environments. COMPENSATION AND BENEFITS: $180,000 - $600,000 USD Base salary is just one part of our total rewards package, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks. Equal opportunity employer. For details on data processing, view the Recruitment Privacy Notice.

🏢 Summary: Opportunity to work on critical AI modeling challenges in a hands-on, high-performance environment focused on building highly useful AI systems. The role emphasizes initiative, strong communication, and collaboration within a flat organizational structure. Compensation includes a high base salary, equity, and comprehensive benefits. 🗂️ Requirements: Belief in truth-seeking AI as an important problem, Strong interest in building useful AI models, Power-user experience with AI models, Strong communication skills, Ability to work hands-on in a meritocratic environment, Strong prioritization and work ethic 📃 Skills: AI, Modeling 🏢 Description: SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company's mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. ABOUT THE ROLE: You will work on the most critical modeling challenges at any given time. You will get clarity on your first project before an offer. BASIC QUALIFICATIONS: You believe truth-seeking AI is the most important and challenging problem. You are obsessed about building incredibly useful models. You are a power user of AI models. If you previously trained models used by millions of people it's a big plus, but modeling experience is not required. You take pride in your work and thrive in meritocratic environments. COMPENSATION AND BENEFITS: $180,000 - $600,000 USD Base salary is just one part of our total rewards package, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks. Equal opportunity employer. For details on data processing, view the Recruitment Privacy Notice.

🏢 Summary: Opportunity to work on critical AI modeling challenges in a hands-on, high-performance environment focused on building useful truth-seeking AI systems. The role emphasizes initiative, strong communication, and engineering excellence, with flexibility around prior large-scale model training experience. 🗂️ Requirements: Belief in truth-seeking AI as a critical problem, Experience using AI models extensively, Strong communication skills, Ability to work hands-on in a flat organization, Strong prioritization and work ethic, Ability to contribute directly to AI modeling challenges 📃 Skills: AI, Modeling 🏢 Description: SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company's mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. ABOUT THE ROLE: You will work on the most critical modeling challenges at any given time. You will get clarity on your first project before an offer. BASIC QUALIFICATIONS: You believe truth-seeking AI is the most important and challenging problem. You are obsessed about building incredibly useful models. You are a power user of AI models. If you previously trained models used by millions of people it's a big plus, but modeling experience is not required. You take pride in your work and thrive in meritocratic environments. COMPENSATION AND BENEFITS: $180,000 - $600,000 USD Base salary is just one part of our total rewards package, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks. Equal opportunity employer. For details on data processing, view the Recruitment Privacy Notice.

🏢 Summary: Role for an exceptional software engineer to tackle the company’s highest-priority AI and technical challenges in a hands-on, high-performance environment. The position emphasizes engineering excellence, initiative, strong communication, and alignment with truth-seeking AI research. Compensation includes high base salary, equity, and comprehensive benefits. 🗂️ Requirements: Exceptional software engineering skills, Strong communication skills, Ability to work hands-on on critical technical challenges, Experience thriving in meritocratic environments, Strong prioritization and initiative, Interest in truth-seeking AI systems 📃 Skills: AI, Software, Engineering 🏢 Description: ABOUT THE ROLE: You will work on the most critical product or technical challenge at any given time. You will get clarity on your first project before an offer. BASIC QUALIFICATIONS: • You believe truth-seeking AI is the most important and challenging problem. • You take pride in your work and thrive in meritocratic environments. • You are an exceptional software engineer. COMPENSATION AND BENEFITS: • $180,000 - $440,000 USD • Base salary is just one part of the total rewards package, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks. • Equal opportunity employer.