Myndstream | Hybrid London, UK | Full time | https://myndstream.com

Music for health and wellbeing - we're working with leading scientists at MIT, NYU and UPenn alongside a roster of composers to create validated music to improve health and wellbeing.

We are on course to enhance the effectiveness & efficacy of our music through the use of ML. We've started with hospitality as a launchpad and are now moving into healthcare markets.

Core Stack: TypeScript, Rust (for low-level audio work), React, PostgreSQL, WebSockets, GCP

If you are enjoy ownership, autonomy, design patterns and are a pragmatic generalist then you will enjoy it here.

Hiring Founding Software Engineers in London, UK, - contact me via email: Email is hidden

Jane Street | Hybrid | Full-time

If you haven't heard of us before, we’re a quantitative trading firm that cares a lot about technology. This means building elegant solutions that scale well, never assuming that “best in market” is the same as “best possible,” and ensuring everybody has the resources needed to do their jobs well.

We're looking for folks in New York, London, Hong Kong, and Singapore for a variety of roles including, but not limited to:

- Data Engineers who can help us understand, clean, manage and share the data that guides our trading. At Jane Street, having a thorough and accurate understanding of data is at the core of everything we do -- https://www.janestreet.com/join-jane-street/position/6558007...

- Machine Learning Engineers with robust experience in machine learning and strong mathematical foundations. Machine learning is a critical pillar of Jane Street's global business. Our ever-evolving trading environment serves as a unique, rapid-feedback platform for ML experimentation, allowing us to incorporate new ideas with relatively little friction -- https://www.janestreet.com/join-jane-street/position/6485460...

- A Machine Learning Educator who will be instrumental in maintaining and growing our ML educational programs and classes, spanning topics such as an introduction to general ML, efficient use of AI assistants, our internal stack for training models, and how to reason about performance -- https://www.janestreet.com/join-jane-street/position/8056588...

- Software Engineers who are intimately tied into every area of our business. We are big believers in functional programming, using OCaml, a statically-typed functional programming language, as our primary development language. We also believe in the value of open source software, using it in our daily work and releasing hundreds of thousands of lines of our own code as open source -- https://www.janestreet.com/join-jane-street/position/4274288...

- Frontend Software Engineers who are passionate about user-interface design and typed functional programming. You would take part in the design and implementation of our next-generation of browser-based tools for operating our trading infrastructure -- https://www.janestreet.com/join-jane-street/position/6184529...

- A Programmer-Who-Writes, or a Writer-Who-Codes -- https://www.janestreet.com/join-jane-street/position/7604415...

Yuma.ai (YC W23) | Senior Full-Stack AI Engineer | Remote (Europe) or Hybrid (Barcelona) | Full-time Ruby + AI Agents = Yuma

Yuma is building a complete orchestration platform that deploys autonomous AI agents dedicated to customer support in e-commerce. We are one of the leaders in this space and we offer one of the most advanced platforms to date, supporting over 100 paying customers. Our agents replicate human capabilities by taking actions and retrieving information from external services as needed.

Our top merchants automate over 80% of their support tickets through Yuma.

Yuma was founded by Guillaume Luccisano, a 3rd time YC founder, and now boasts a team of 18 highly dedicated, talented people driven to deliver the best value to our customers through AI.

Learn more & apply here: https://yuma.ai/work-at-yuma

Elicit | San Francisco + remote (US timezones) | https://elicit.com/careers

Elicit is an AI research assistant that uses language models to help researchers figure out what’s true and make better decisions. We scaled to >$6MM annual revenue and 450k MAU fast. We're hiring for multiple roles and are primarily interested in people with early-stage company experience, who are comfortable in high-agency, fast-paced teams.

Reasons you might want to join Elicit:

1. We have been thinking about how to apply AI for high-stakes knowledge work since even before GPT-1. Elicit was spun-out from Ought (https://ought.org/) which was an applied research lab.

2. If you're concerned about the potential downsides and risks of super-powerful AI: so are we! Happy to explain more of this story on a call, or you can also check e.g. https://ought.org/updates/2022-04-06-process for a primer.

3. We like spending time with each other, and have get-togethers every 6 weeks, but we're flexible on location.

Reasons you might not want to join Elicit:

1. We've found a level of product market fit (as evidenced by metrics) but we've not proven everything out yet. If you want predictability, Elicit is not for you.

2. We aim to hire people who thrive in low-bureaucracy environments, and let them loose. If you need structure, lots of support, close mentorship, or tightly-defined work assignments, Elicit is not for you.

A selection of open roles—more on the site:

• Machine learning engineer: https://elicit.com/careers?ashby_jid=913a03d5-bd26-4c64-8346...

• Our first data engineer: https://elicit.com/careers?ashby_jid=4617f630-f971-4716-b753...

• Front-end engineer: https://elicit.com/careers?ashby_jid=b5e218b8-8730-4254-b026...

ZipFit | Staff Software Engineer | REMOTE | Full-time | $140K-180K

ZipFit is building the future of fitness studio management with an AI-powered, all-in-one platform for fitness businesses. Our platform streamlines operations, boosts client retention, and provides operational analytics. We are a product-obsessed team creating the next generation of software for a passionate industry eager for change.

We're seeking a Staff Software Engineer to be a core member of our engineering team. You will own critical systems, designing and deploying robust, scalable, full-stack solutions - from the UI to the database and infrastructure.

You'll work on products like: CRM and Member Management, Web Hosting Infrastructure, Email & SMS Marketing, Events, Classes, and Appointment bookings, and a Member App (PWA).

Our stack: * **Backend**: TypeScript, Node.js, NestJS, Remix * **Frontend**: TypeScript, React, Tailwind * **Infrastructure**: Amazon Web Services (AWS)

We're looking for someone with: * 8+ years of software engineering experience and a portfolio of shipped products. * Proficiency across the stack, with deep expertise in TypeScript, Node.js, React, and AWS DevOps. * An architectural mindset, understanding design patterns and building for scale. * Extreme ownership, thriving in an autonomous environment. * A pragmatic approach, balancing speed with quality.

Please send resume to kerry, the at symbol, joinzipper.com

Archera | Senior Data Engineer | REMOTE (US/Canada) or Hybrid (Seattle) | Full-time

Archera empowers organizations of all sizes to optimize their cloud costs through unique, short-term, insured GRI (Guaranteed Reserved Instance) and GSP (Guaranteed Savings Plan) commitments.

We’re looking for a Senior Data Engineer to build and scale the data backbone of Archera’s cloud cost optimization products. This role focuses on architecting large-scale data pipelines that process cloud billing and usage data across AWS, Azure, and GCP. You’ll work across OLTP and OLAP systems to ensure our data infrastructure is performant, reliable, and purpose-built for FinOps. Your work will enable accurate cost modeling, insights, and automation that directly power Archera’s cloud rate insurance platform.

Stack: Python (SQLAlchemy, Flask), TypeScript (React), PostgreSQL, Snowflake, Argo Workflows, k8s, AWS/GCP/Azure

Benefits: RRSP/401k match, healthcare, stock, wework/home office expenses.

Apply: https://job-boards.greenhouse.io/archera/jobs/4788177008 and email me at simon+hn <at> archera <dot> ai

Datadog | Software Engineers | ONSITE (Boston, Lisbon, Madrid, NYC, Paris, Tel Aviv) | Full-time

Datadog is a monitoring, tracing, logs system, and more, for your infrastructure and services. We build our own tsdb, event store [1][2], distributed tracing tools, cutting edge visualizations, and more. We love shipping great experiences for customers just like us and are growing fast! We write a lot of Go, Java, Python, Typescript (with React), and a bit of other languages. We run on k8s, and are multi-region and multi-cloud.

We're looking for people who can build systems at scale as we process trillions of events per day. Let us know if that's you!

https://dtdg.co/hnwhoshiring

[1] https://www.datadoghq.com/blog/engineering/introducing-husky

[2] https://www.datadoghq.com/blog/engineering/husky-deep-dive

360Me | Founding CTO & iOS Engineer | London / UK | Full-time | AI, Precision Health, Aging

We're building 360Me: an AI-driven platform that helps people measure and reverse their biological age using diagnostics, wearables, and real-time insights. Backed by clinical validation and a world-class product team, we're turning fragmented health data into personalized, impactful action.

We’re hiring a Founding CTO to lead and scale our technical foundations — and an experienced iOS Engineer to help deliver a seamless mobile experience from day one.

Founding CTO (AI, Infra, Health) You’ll architect, build, and scale the entire tech stack from 0→1, then grow the team around what works. You’ll ship our food analysis API (image/audio/text → nutrient vector), build real-time infra with GCP/Vertex AI/Terraform, and lead engineering through our first clinical pilot. You’ll own core technical decisions, contribute code, and eventually hire and mentor a high-performing team.

You Likely Have: 10+ yrs engineering experience, 5+ in AI/ML or data-intensive systems • Proven 0→1 track record (healthtech, biotech, or regulated SaaS ideal) • Comfortable writing production code and scaling systems • PhD/DPhil or deep experience in CS, AI, Physics, or Computational Bio (bonus)

$160k–$200k + equity

Apply: 360me.typeform.com/CTOApp

Note: Our process includes two technical case studies, designed to simulate real decisions you’ll face here.

iOS Engineer (SwiftUI, HealthKit, Wearables) 7+ yrs iOS experience, including 2+ with SwiftUI • Shipped 2+ production iOS apps • Integrated HealthKit and wearables (e.g. Oura, Withings) in production • Experience with Realm, RevenueCat, AWS • CI/CD fluency with GitHub Actions, Xcode Cloud, Fastlane

Bonus: WatchOS apps, familiarity with modern AI dev tools, HIPAA/GDPR knowledge • UK-based (London hybrid ideal)

$90k–$115k + stock options

Apply: 360me.typeform.com/fullstackdev

HomeCloud | Senior Cloud Engineer (AWS / Node.js / TypeScript) | Remote (US, EU UTC-6 to UTC+2) | Full-Time (Contractor)

HomeCloud is a fast-growing proptech startup rethinking home inspections, onboarding, and management using cloud-native systems and AI. We just raised a $3.5M seed round from top VCs and are building intelligent infrastructure for the future of homeownership.

We’re looking for a Senior Cloud Engineer to help us build scalable backend systems on AWS using Lambda, Step Functions, DynamoDB, EventBridge, and more. You’ll work with a modern serverless stack, integrate AI services (e.g. OpenAI, Bedrock), and help define our engineering culture alongside the CTO and founding team.

You might be a fit if you: • Have 5+ years of experience building serverless systems on AWS • Are fluent in Node.js + TypeScript • Have worked with serverless architecture and event-driven systems • Are curious about AI/LLM APIs and how to integrate them into real-world workflows • Value ownership, pragmatism, and building useful products quickly

This is a high-impact, remote-first role on a small, focused team building the foundation of a data-rich, AI-powered platform.

Remote (UTC-6 to UTC+2) Early-stage, fast-moving environment Apply: https://app.dover.com/apply/homecloud/24919848-66d7-48c0-bf5... Learn more: https://gethomecloud.com/about-us

Lumafield | https://www.lumafield.com SAN FRANCISCO, CA or CAMBRIDGE, MA – ONSITE

About Lumafield: Lumafield was founded in 2019 to upgrade manufacturing by making the most advanced tools more accessible. Our AI-driven platform and industrial CT scanning technology give engineers unprecedented visibility into their products, helping them make better decisions, faster. We’re headquartered in Cambridge, MA, with an office in San Francisco, CA. Lumafield is building the future of manufacturing through deeper insights, greater autonomy, and continuous innovation.

We recently raised our Series C funding of $75 million, further accelerating our mission to revolutionize manufacturing.

Open Roles: Backend Software Engineer (SF Bay Area) | Research Engineer (Greater Boston Area) | DevOps Engineer (SF Bay Area) | IT Specialist (SF Bay Area) | UX Designer (SF Bay Area)

Don't see a role you're looking for? Visit our careers page (https://www.lumafield.com/careers) and send us a message!