BJAK Logo

BJAK

Machine Learning Engineer, Ranking & Retrieval

Posted 2 Months Ago
Remote or Hybrid
Hiring Remotely in United Kingdom
Mid level
Remote or Hybrid
Hiring Remotely in United Kingdom
Mid level
Build and operate ML infrastructure for training, evaluation, deployment, inference, and experimentation. Improve reliability, scalability, latency, throughput, and cost efficiency. Create reproducible pipelines, observability, benchmarking, and platform tooling enabling researchers and engineers to ship models to production.
The summary above was generated by AI
About

There are over 5 billion users using basic applications today such email, notes, tasks, calendar and they're not AI-native. Our mission is to build proactive applications for anyone in the world, who are not used to complex prompting. We aim to bring intelligence to conversations, errands, organising and workflows, with minimal to no prompting.

Our first application is an agent-first mobile communication app. We believe building applications that users use daily for communication, coordination and collaboration needs will help integrate AI into their lives. The net effect is to eliminate misinformation, achieve low coordination costs, enable high quality tasks and collaboration at scale with minimal or little prompting.

 
Role

Build and improve ML systems that power our AI-native applications.

Work on classification, retrieval, ranking, personalization and evaluation, taking ownership from model development to production deployment.

This role is for engineers who enjoy solving practical ML problems, improving model quality and shipping reliable systems used by real users.

 
Focus
  • Build and improve ML models for classification, ranking, retrieval and personalization.

  • Develop efficient classifiers and optimize model accuracy, precision, latency and cost.

  • Improve search relevance and context retrieval using embeddings, hybrid search and reranking.

  • Build personalization models that learn from user behavior while respecting privacy.

  • Develop evaluation pipelines, labeled datasets and metrics to measure model quality.

  • Fine-tune and adapt existing models when supported by sufficient data.

  • Build and maintain ML training, inference and deployment pipelines.

  • Debug production issues, monitor model performance and ship improvements based on real-world feedback.

 
Tech Stack
  • Python

  • PyTorch / JAX

  • Embeddings, vector search and ranking models

  • Production ML systems and inference pipelines

 
Ideal Experience
  • Strong foundations in machine learning and modern neural architectures.

  • Hands-on experience building and deploying ML models in production.

  • Experience in classification, ranking, retrieval, recommendation systems or personalization.

  • Understanding of model evaluation, experimentation and performance metrics.

  • Comfortable writing production-quality code and working with real-world datasets.

  • Able to balance model quality, latency, cost and reliability.

  • Strong ownership, problem-solving skills

 
Outcomes
  • ML models in production meet expected accuracy, relevance, latency and reliability targets.

  • Classification and ranking improvements deliver measurable gains in model quality.

  • Evaluation pipelines identify regressions and support reliable model releases.

  • Training, inference and data pipelines are robust, reproducible and maintainable.

  • Model improvements are driven by real-world feedback and measurable results.

  • Collaborates effectively with engineering and product teams to deliver reliable ML-powered features.

 
How We Work

The best products in the world are built by small, world-class teams. We are a high-talent-density, hands-on team. We make decisions collectively and move quickly, balancing high-quality work with continuous learning.

Joining our team requires the ability to bring structure, exercise judgment and execute independently. Our goal is to put a truly magical product into the hands of our users.

 
Interview Process

If there appears to be a fit, we'll reach out to schedule 3, but no more than 4 interviews.

Applications are evaluated by our technical team members. Interviews will be conducted virtually and/or onsite.

We value transparency and efficiency, so expect a prompt decision. If you've demonstrated the exceptional skills and mindset we're looking for, we'll extend an offer to join us.

Similar Jobs

26 Minutes Ago
Easy Apply
Remote
United Kingdom
Easy Apply
Entry level
Entry level
Cloud • Security • Software • Cybersecurity • Automation
Develop and maintain secure, reliable backend services for GitLab repository workflows using Ruby and GraphQL. Responsibilities include designing APIs and data models, optimizing SQL queries and performance, implementing caching and rate limiting, testing, troubleshooting, monitoring production systems, participating in Tier 2 on-call, improving observability, and collaborating asynchronously across engineering and product teams.
Top Skills: GitGit Large File Storage (Lfs)GitalyGraphQLRelational DatabasesRubySQL
3 Hours Ago
Easy Apply
Remote or Hybrid
UK
Easy Apply
Senior level
Senior level
Cloud • Information Technology • Security • Software • Cybersecurity
Build scalable backend systems, data pipelines, APIs, and services for Zscaler’s Threat Intelligence team. Process and index large volumes of threat data, improve performance and engineering practices, and collaborate with malware reverse engineering teams to enhance threat detection. The role requires Python, PostgreSQL, Redis, distributed systems, REST APIs, SQL optimization, and backend database expertise, with preferred experience in AI/LLM workflows, malware automation, Django, Kubernetes, and search engines.
Top Skills: Distributed Task QueuesDjangoElasticsearchKubernetesLlmsMeilisearchPostgresPythonRedisRestful ApisSQLTypesense
6 Hours Ago
Remote or Hybrid
UK
Senior level
Senior level
HR Tech • Information Technology • Professional Services • Sales • Software
Own premium technical and strategic support for enterprise B2B SaaS customers. Build knowledge of customer configurations and business goals, lead planning and training sessions, investigate complex issues, coordinate escalations, and maintain proactive communication. Partner with Customer Success, Product, Engineering, and Implementation teams during critical HR cycles and module launches. Identify recurring issues, improve processes, create documentation, and help enhance support through AI and automation.
Top Skills: Ai PlatformsAPIsAsanaHrisIntegrationsJIRASalesforceSlackSupport AutomationZendesk

What you need to know about the Belfast Tech Scene

If asked to name the birthplace of the RMS Titanic, you might not say Belfast. Similarly, if asked to name Europe's leading destination for foreign direct investment in new software development, Belfast might not come to mind. Yet, both are true. The city has emerged as a tech powerhouse, recently ranked among the best in the U.K. for tech careers — especially for software developers. It also leads the U.K. with the highest percentage of software development jobs advertised.

Sign up now Access later

Create Free Account

Please log in or sign up to report this job.

Create Free Account