Bjak is hiring: Founding Machine Learning Engineer in New York
Bjak, New York, NY, United States
Transform language models into real-world, high-impact product experiences.
A1 is a self-funded AI group, operating in full stealth. We’re building a new global consumer AI application focused on an important but underexplored use case.
You will shape the core technical direction of A1 - model selection, training strategy, infrastructure, and long-term architecture. This is a founding technical role: your decisions will define our model stack, our data strategy, and our product capabilities for years ahead.
You won’t just fine-tune models - you’ll design systems: training pipelines, evaluation frameworks, inference stacks, and scalable deployment architectures. You will have full autonomy to experiment with frontier models (LLaMA, Mistral, Qwen, Claude-compatible architectures) and build new approaches where existing ones fall short.
Why This Role Matters
You are creating the intelligence layer of A1’s first product, defining how it understands, reasons, and interacts with users.
Your decisions shape our entire technical foundation — model architectures, training pipelines, inference systems, and long-term scalability.
You will push beyond typical chatbot use cases, working on a problem space that requires original thinking, experimentation, and contrarian insight.
You influence not just how the product works, but what it becomes, helping steer the direction of our earliest use cases.
You are joining as a founding builder, setting engineering standards, contributing to culture, and helping create one of the most meaningful AI applications of this wave.
What You’ll Do
Build end-to-end training pipelines: data → training → eval → inference
Design new model architectures or adapt open-source frontier models
Fine-tune models using state-of-the-art methods (LoRA/QLoRA, SFT, DPO, distillation)
Architect scalable inference systems using vLLM / TensorRT-LLM / DeepSpeed
Build data systems for high-quality synthetic and real-world training data
Develop alignment, safety, and guardrail strategies
Design evaluation frameworks across performance, robustness, safety, and bias
Own deployment: GPU optimization, latency reduction, scaling policies
Shape early product direction, experiment with new use cases, and build AI-powered experiences from zero
Explore frontier techniques: retrieval-augmented training, mixture-of-experts, distillation, multi-agent orchestration, multimodal models
What It’s Like to Work Here
You take ownership - you solve problems end-to-end rather than wait for perfect instructions
You learn through action - prototype → test → iterate → ship
You’re calm in ambiguity - zero-to-one building energises you
You bias toward speed with discipline - V1 now > perfect later
You see failures and feedback as essential to growth
You work with humility, curiosity, and a founder’s mindset
You lift the bar for yourself and your teammates every day
Requirements
Strong background in deep learning and transformer architectures
Hands-on experience training or fine-tuning large models (LLMs or vision models)
Proficiency with PyTorch, JAX, or TensorFlow
Experience with distributed training frameworks (DeepSpeed, FSDP, Megatron, ZeRO, Ray)
Strong software engineering skills — writing robust, production-grade systems
Experience with GPU optimization: memory efficiency, quantization, mixed precision
Comfortable owning ambiguous, zero-to-one technical problems end-to-end
Nice to Have
Experience with LLM inference frameworks (vLLM, TensorRT-LLM, FasterTransformer)
Contributions to open-source ML libraries
Background in scientific computing, compilers, or GPU kernels
Experience with RLHF pipelines (PPO, DPO, ORPO)
Experience training or deploying multimodal or diffusion models
Experience in large-scale data processing (Apache Arrow, Spark, Ray)
Prior work in a research lab (Google Brain, DeepMind, FAIR, Anthropic, OpenAI)
What You’ll Get
Extreme ownership and autonomy from day one - you define and build key model systems.
Founding-level influence over technical direction, model architecture, and product strategy.
Remote-first flexibility
High-impact scope—your work becomes core infrastructure of a global consumer AI product.
Competitive compensation and performance-based bonuses
Backing of a profitable US$2B group, with the speed of a startup
Insurance coverage, flexible time off, and global travel insurance
Opportunity to shape a new global AI product from zero
A small, senior, high-performance team where you collaborate directly with founders and influence every major decision.
Our Team & Culture
We operate as a dense, senior, high-performance team. We value clarity, speed, craftsmanship, and relentless ownership. We behave like founders — we build, ship, iterate, and hold ourselves to a high technical bar.
If you value excellence, enjoy building real systems, and want to be part of a small team creating something globally impactful, you’ll thrive here.
About A1
A1 is a self-funded, independent AI group backed by BJAK, focused on building a new consumer AI product with global impact. We’re assembling a small, elite team of ML and engineering builders who want to work on meaningful, high-impact problems.
#J-18808-Ljbffr
In Summary: A1 is a self-funded AI group, operating in full stealth . We’re building a new global consumer AI application focused on an important but underexplored use case . You will shape the core technical direction of A1 - model selection, training strategy, infrastructure, and long-term architecture .
En Español: Transformar los modelos de lenguaje en experiencias reales de productos de alto impacto. A1 es un grupo de IA autofinanciado, que opera con total sigilo. Estamos construyendo una nueva aplicación global de inteligencia artificial para el consumidor centrada en un caso de uso importante pero aún no explorado. Diseñarás la dirección técnica principal de A1 - selección del modelo, estrategia de capacitación, infraestructura y arquitectura a largo plazo. Este es un papel técnico fundamental: tus decisiones definirán nuestra pila de modelos, nuestra estrategias de datos y nuestras capacidades de producto durante años venideros. Tendrá plena autonomía para experimentar con modelos fronterizos (LLaMA, Mistral, Qwen, arquitecturas compatibles con la GPU Claude) y construir nuevos enfoques donde los existentes no son suficientes. Aquí está creando la capa de inteligencia del primer producto A1, definiendo cómo entiende, razona e interactúa con los usuarios. Sus decisiones dan forma a toda nuestra base técnica arquitectura de modelo, tuberías de entrenamiento, sistemas de inferencias y escalabilidad a largo plazo. Irás más allá de los casos típicos de uso de chatbot, trabajando en un espacio problemático que requiere pensamiento original, experimentación y perspicacia contraria. Aquí influye no solo en cómo funciona el producto Deep, sino en lo que se convierte, dirigiendo la dirección de nuestros primeros casos de uso. Te estás uniendo como agente fundador, contribuyendo al desarrollo de las normas de ingeniería avanzadas, contribuyéndole a una nueva línea de trabajo - ¿Qué es la capacidad de diseño? Valoramos la claridad, velocidad, artesanía y propiedad implacable. Nos comportamos como fundadores construimos, enviamos, iteramos y nos mantenemos en una alta barra técnica. Si valoras la excelencia, disfrutas de construir sistemas reales y quieres formar parte de un pequeño equipo que crea algo impactante a nivel mundial, prosperarás aquí. Sobre A1 A1 es un grupo autónomo e independiente de inteligencia artificial respaldado por BJAK, enfocado en construir un nuevo producto de IA para el consumidor con impacto global. Estamos reuniendo un equipo pequeño y élite de constructores de ingeniería ML que quieren trabajar en problemas significativos y de alto impacto. # J-18808-Ljbffr
A1 is a self-funded AI group, operating in full stealth. We’re building a new global consumer AI application focused on an important but underexplored use case.
You will shape the core technical direction of A1 - model selection, training strategy, infrastructure, and long-term architecture. This is a founding technical role: your decisions will define our model stack, our data strategy, and our product capabilities for years ahead.
You won’t just fine-tune models - you’ll design systems: training pipelines, evaluation frameworks, inference stacks, and scalable deployment architectures. You will have full autonomy to experiment with frontier models (LLaMA, Mistral, Qwen, Claude-compatible architectures) and build new approaches where existing ones fall short.
Why This Role Matters
You are creating the intelligence layer of A1’s first product, defining how it understands, reasons, and interacts with users.
Your decisions shape our entire technical foundation — model architectures, training pipelines, inference systems, and long-term scalability.
You will push beyond typical chatbot use cases, working on a problem space that requires original thinking, experimentation, and contrarian insight.
You influence not just how the product works, but what it becomes, helping steer the direction of our earliest use cases.
You are joining as a founding builder, setting engineering standards, contributing to culture, and helping create one of the most meaningful AI applications of this wave.
What You’ll Do
Build end-to-end training pipelines: data → training → eval → inference
Design new model architectures or adapt open-source frontier models
Fine-tune models using state-of-the-art methods (LoRA/QLoRA, SFT, DPO, distillation)
Architect scalable inference systems using vLLM / TensorRT-LLM / DeepSpeed
Build data systems for high-quality synthetic and real-world training data
Develop alignment, safety, and guardrail strategies
Design evaluation frameworks across performance, robustness, safety, and bias
Own deployment: GPU optimization, latency reduction, scaling policies
Shape early product direction, experiment with new use cases, and build AI-powered experiences from zero
Explore frontier techniques: retrieval-augmented training, mixture-of-experts, distillation, multi-agent orchestration, multimodal models
What It’s Like to Work Here
You take ownership - you solve problems end-to-end rather than wait for perfect instructions
You learn through action - prototype → test → iterate → ship
You’re calm in ambiguity - zero-to-one building energises you
You bias toward speed with discipline - V1 now > perfect later
You see failures and feedback as essential to growth
You work with humility, curiosity, and a founder’s mindset
You lift the bar for yourself and your teammates every day
Requirements
Strong background in deep learning and transformer architectures
Hands-on experience training or fine-tuning large models (LLMs or vision models)
Proficiency with PyTorch, JAX, or TensorFlow
Experience with distributed training frameworks (DeepSpeed, FSDP, Megatron, ZeRO, Ray)
Strong software engineering skills — writing robust, production-grade systems
Experience with GPU optimization: memory efficiency, quantization, mixed precision
Comfortable owning ambiguous, zero-to-one technical problems end-to-end
Nice to Have
Experience with LLM inference frameworks (vLLM, TensorRT-LLM, FasterTransformer)
Contributions to open-source ML libraries
Background in scientific computing, compilers, or GPU kernels
Experience with RLHF pipelines (PPO, DPO, ORPO)
Experience training or deploying multimodal or diffusion models
Experience in large-scale data processing (Apache Arrow, Spark, Ray)
Prior work in a research lab (Google Brain, DeepMind, FAIR, Anthropic, OpenAI)
What You’ll Get
Extreme ownership and autonomy from day one - you define and build key model systems.
Founding-level influence over technical direction, model architecture, and product strategy.
Remote-first flexibility
High-impact scope—your work becomes core infrastructure of a global consumer AI product.
Competitive compensation and performance-based bonuses
Backing of a profitable US$2B group, with the speed of a startup
Insurance coverage, flexible time off, and global travel insurance
Opportunity to shape a new global AI product from zero
A small, senior, high-performance team where you collaborate directly with founders and influence every major decision.
Our Team & Culture
We operate as a dense, senior, high-performance team. We value clarity, speed, craftsmanship, and relentless ownership. We behave like founders — we build, ship, iterate, and hold ourselves to a high technical bar.
If you value excellence, enjoy building real systems, and want to be part of a small team creating something globally impactful, you’ll thrive here.
About A1
A1 is a self-funded, independent AI group backed by BJAK, focused on building a new consumer AI product with global impact. We’re assembling a small, elite team of ML and engineering builders who want to work on meaningful, high-impact problems.
#J-18808-Ljbffr
In Summary: A1 is a self-funded AI group, operating in full stealth . We’re building a new global consumer AI application focused on an important but underexplored use case . You will shape the core technical direction of A1 - model selection, training strategy, infrastructure, and long-term architecture .
En Español: Transformar los modelos de lenguaje en experiencias reales de productos de alto impacto. A1 es un grupo de IA autofinanciado, que opera con total sigilo. Estamos construyendo una nueva aplicación global de inteligencia artificial para el consumidor centrada en un caso de uso importante pero aún no explorado. Diseñarás la dirección técnica principal de A1 - selección del modelo, estrategia de capacitación, infraestructura y arquitectura a largo plazo. Este es un papel técnico fundamental: tus decisiones definirán nuestra pila de modelos, nuestra estrategias de datos y nuestras capacidades de producto durante años venideros. Tendrá plena autonomía para experimentar con modelos fronterizos (LLaMA, Mistral, Qwen, arquitecturas compatibles con la GPU Claude) y construir nuevos enfoques donde los existentes no son suficientes. Aquí está creando la capa de inteligencia del primer producto A1, definiendo cómo entiende, razona e interactúa con los usuarios. Sus decisiones dan forma a toda nuestra base técnica arquitectura de modelo, tuberías de entrenamiento, sistemas de inferencias y escalabilidad a largo plazo. Irás más allá de los casos típicos de uso de chatbot, trabajando en un espacio problemático que requiere pensamiento original, experimentación y perspicacia contraria. Aquí influye no solo en cómo funciona el producto Deep, sino en lo que se convierte, dirigiendo la dirección de nuestros primeros casos de uso. Te estás uniendo como agente fundador, contribuyendo al desarrollo de las normas de ingeniería avanzadas, contribuyéndole a una nueva línea de trabajo - ¿Qué es la capacidad de diseño? Valoramos la claridad, velocidad, artesanía y propiedad implacable. Nos comportamos como fundadores construimos, enviamos, iteramos y nos mantenemos en una alta barra técnica. Si valoras la excelencia, disfrutas de construir sistemas reales y quieres formar parte de un pequeño equipo que crea algo impactante a nivel mundial, prosperarás aquí. Sobre A1 A1 es un grupo autónomo e independiente de inteligencia artificial respaldado por BJAK, enfocado en construir un nuevo producto de IA para el consumidor con impacto global. Estamos reuniendo un equipo pequeño y élite de constructores de ingeniería ML que quieren trabajar en problemas significativos y de alto impacto. # J-18808-Ljbffr