Ask HN: Who is hiring? (September 2025)

Rappo | https://buildrappo.com | Founding Applied AI Engineer | Remote or Onsite SF

Hi, we have been working on a personal assistant for knowledge professionals. A lot of challenges around building an advanced RAG, improving reasoning, and custom models

Learn more about the role: https://wellfound.com/jobs/3382533-senior-ai-ml-engineer or email [email protected]

PS: I am a solo founder, and we are generous with equity

Y Combinator (yes, the people who run this site) | Full stack web and AI | San Francisco | Onsite | Fulltime

YC itself hires software engineers from time to time. Many people don't know that YC has a small but very important software team. We run several websites - not just this one, but also workatastartup.com (the main way YC companies hire), a social network for YC founders, and the core infrastructure that YC itself runs on.

Recently, we've been spending most of our time building our own AI agents. Over the last year, YC has mostly funded AI agent companies, so it's been cool to go really deep building our own AI agents too. We're building agents to automate every aspect of what we do, and pushing the limits of what's possible with the current models to do it.

An unusual aspect of being on the YC software team is that you'll get full access to the YC program, founders and partners. The YC batch runs in the same building we work out of, so there are talks with famous founders happening most nights, right downstairs in our building. If you want to start a startup someday, working at YC would be an excellent jumping off point - several YC companies have come from team members who decided to start their own company.

YC works fully in-person in SF. We're happy to help you move here if you're in the US already. Unfortunately we can't sponsor new visas, but we're happy to transfer existing ones.

YC offers highly competitive compensation and benefits.

You can apply online (https://www.ycombinator.com/careers) or just email me at [email protected]

SerpApi | https://serpapi.com | Junior to Senior Fullstack Engineer multiple positions | Customer Success Engineer | Hiring Coordinator | Python/Ruby/PHP/Js/Rust/Cotlin/C#/Crystal/Nim/Elixir Developer Advocate positions | Based in Austin, TX but remote-first structure | Full-time | ONSITE or FULLY REMOTE | $150K - 180K a year 1099 for US or local avg + 20% for outside the US

SerpApi is the leading API to scrape and parse search engine results. We deeply support Google, Google Maps, Google Images, Bing, Baidu, and a lot more.

Our current stack is Ruby, Rails, MongoDB, and React.JS. We are looking for more Junior and Senior FullStack Engineers. We have an awesome work environment: We are a remote first company (before Covid!). We do continuous integration, continuous deployments, code reviews, code pairings, profit sharing, and most of communication is async via GitHub.

We value super strongly transparency, do open books, have a public roadmap, and contribute to the EFF.

Apply at: https://serpapi.com/careers

Moyai | Amsterdam, The Netherlands | Full Time | Onsite | Founding AI Engineer | 60k-80k + Equity

About the company:

• Technical founding team with relevant industry experience (part of Nvidia Inception Program)

• Backed by well-known European VCs (SpeedInvest+Galion.exe)

• Building agentic advanced analytics and fine-tuning analytical reasoning models

Ideal candidate:

• Demonstrated shipping ability with past projects & roles

• "Young and hungry” mindset, prioritising ability to learn with agency over experience

• Familiar with fine-tuning algorithms and frameworks, transformers/trl, ART, verl and unsloth

• Bonus points for experience in contributing to open-source projects, startups, AI agents, & similar technologies

Reach out to the founder directly: https://www.linkedin.com/in/rhommes/

Kaedim | Software Engineer, Machine Learning Engineer, Customer Support Engineer, Product Manager, Founding Recruiter | Onsite | Full-time | San Francisco, Singapore, London | US & UK Sponsorship Available Kaedim is an AI startup building ML algorithms that turn images into digital 3d models. We are a group of ~10 looking to grow the team to help streamline 3d content creation for 3d artists and are already working with 1 of the top 10 games of all time! Using our AI and in-house art team, we have the most accurate, game-ready 2d → 3d asset generation pipeline. Currently, we are offering a 10x speed up to 3D asset creation pipelines of 200+ game developers and we are working with partners like Voodoo, Upland, Azra Games. Check out our demo here: https://www.youtube.com/watch?v=tlQWFG1DLb0

Job descriptions and application link: https://join-kaedim.notion.site/

Tech Stack:

Product (web app, API): React, MySQL, NodeJS, Python, AWS

Machine Learning: Python, PyTorch, AWS

Undetect.io | Counter-Security / Reverse Engineer | Full Time / Part Time | Remote, Global

We're looking for a TypeScript engineer to join our team with a tight focus on stealth browser automation tools and RE / adversary intelligence pipelines.

You should have:

• Strong TypeScript, Node.js, CDP (Chrome Devtools Protocol) experience.

• Interest in C++ and Chromium internals.

• Experience evading or analyzing anti-bot and WAF systems.

• Practical experience reverse engineering & deobfuscation of heavily obfuscated / defended JavaScript.

• Intermediate / advanced understanding of browser fingerprinting and distributed proxy systems (or eagerness to learn).

• Able to provide examples of clean, maintainable code.

• Familiarity with Docker, Cloudflare Workers, and basic devops.

We're a lean, fast-moving team working on hard problems with real-world impact for enterprise clients, including many Y-Combinator success stories.

Email us: [email protected]

We are LIFEPOWR! Antwerp (Belgium) | Full-time | Remote (Europe) or hybrid (Antwerp) | https://www.lifepowr.io/en/about-us/career

A young and dynamic company, active in energy transition and scaling up!

We are looking for a OPS Application & AI Developer

Your role will be:

-Customizing and maintaining our ERP platform hosted on Odoo.sh

-Developing custom modules, integrating third-party tools, optimizing workflows

-Supporting our internal teams with technical solutions

Send your back-end development expertise and your understanding of Odoo.sh!

Make sure to send your resume, GitHub profile (if available), and examples of past Odoo customizations to [email protected], including “OPS Application & AI Developer - Hacker news” in the subject line.

Come work with me @ AllTrails and help lead our full-stack, frontend, backend, and mobile teams.

Role: Director of Engineering — AllTrails (San Francisco / Remote)

About Us: AllTrails is the most trusted platform for outdoor exploration, helping millions of people discover and enjoy trails every day. We’re consistently ranked among the top Health & Fitness apps and were named Apple’s App of the Year in 2023.

Role Overview: You’ll lead multiple engineering teams across the stack, set technical strategy, and work closely with product and design to deliver a high-quality experience for our global community.

What We’re Looking For: • 10+ years of software engineering experience, with 5+ years in engineering leadership • Experience managing multi-disciplinary teams (frontend, backend, mobile) • Strength in technical architecture, team development, and cross-functional collaboration

Compensation & Benefits: • Competitive salary, equity, comprehensive benefits, unlimited PTO, monthly “Trail Days,” and a collaborative, mission-driven culture.

Ploid AI | Barcelona, Spain | HYBRID (preferably on-site) | Founding Engineers | Full-time + Equity

We’re building an AI-first bioinformatics platform to empower plant breeders and life science researchers with agentic AI and LLMs. Backed by pre-seed funding and real demand from biotech and seed companies, we’re looking for versatile founding engineers to help us shape the future of AI in genomics.

What you’ll do:

• Architect and build AI workflows, agentic interfaces, and data pipelines

• Work across the stack: Go, Python, TypeScript

• Contribute to system design, infrastructure (AWS, Docker, Terraform), and devops

• Collaborate closely with scientists and iterate from prototype to product

• Help define our technical culture and roadmap as a core founding member

Nice-to-haves (not all required): LLM integration, RAG systems, gRPC, scientific computing, cloud/on-prem hybrid systems

About us: We’re an early team of engineers and scientists with strong academic and industry backgrounds (ex-BCG, PhD in Plant Biotech, M.Sc. AI). We’re committed to building something impactful, technical, and genuinely useful for life science.

Apply: [email protected]

More about us: https://ploid.ai

We also consider internship requests from strong student candidates.

Update to our August post: Thank you for all the interest from HN! We have filled 2 out of the 3 open positions. We are now seeking for expertise in full-stack development.

fleming.de | Full Stack Engineer | Magdeburg, Berlin, Hybrid (Germany) | Full Time | German required

Fleming (www.fleming.de) is digitalizing financing for health professionals. We are building and maintaining a React-Native / Nestjs based bank account frontend and a Salesforce base loan sales platform with a Ruby on Rails frontend. We are looking for a well-rounded engineer. You don't have to know the technologies we are using if you bring the conceptual knowledge and the drive to learn.

Some German language knowledge is required since you are going to build German UIs

more info: https://fleming.de/jobs/

Contact [email protected]

Brilliant.org | Software Engineers & Designers | Remote (North America), SF, NYC | Full-time | $170k — $235k | https://brilliant.org

Brilliant is building world-class interactive learning experiences that combine challenging problems, compelling narratives, and delightful visual storytelling.

We're hiring engineers and designers to help craft the next generation of interactive learning and change how the world learns.

Engineers at Brilliant think about both "building the right thing" AND "building the thing right" while pursuing high standards of excellence for ourselves, our product, and our codebase.

Our designers craft interaction patterns that make hard math, science, and computer science concepts feel approachable, delightful, and addictively learnable.

If you're energized by the prospect of doing the best work of your career and changing how the world learns alongside the most talented peers you've ever worked with, you can learn more and apply here: https://brilliant.org/careers.

CredCore | Engineering | Full-time | US/India | www.credcore.com

CredCore helps companies analyze Credit Agreements using AI. We are looking to hire an Engineering Lead with 10+ years of experience. You should be familiar with design patterns and software architecture, infra/kubernetes, and TypeScript/Python. If you’re interested, please reach out to us at [email protected].

A cover letter is not necessary. But please share your resume and links to your GitHub/GitLab/StackOverflow/other profile, or blog/papers, or other portfolio we can review before setting up the interviews.

MONUMENTAL | https://www.monumental.co/ | Amsterdam, The Netherlands | Full Time | Onsite

We make robots that autonomously construct buildings. We are currently developing and manufacturing our autonomous bricklaying system in the beautiful centre of Amsterdam. And our robots are already earning real revenue operating on construction sites all over the Netherlands.

We're looking for experienced FULL-STACK ENGINEERS who can help us solve problems like:

- Data sync and analytics queries across a fleet of robots (that can be offline for hours at a time)

- Rapid deployment and iteration of experimental software changes across firmware, control software and UI

- Modelling buildings in code and finding the right UI for operators to edit them

Check out the progress we've already made on Atrium, our operating system for robotics: https://www.monumental.co/atrium

We're rapidly scaling up operations and we need experienced, generalist engineers who can build the systems that manage all of that complexity. If you think that 'full-stack' could reasonably mean debugging firmware, mixing buckets of mortar _and_ writing React components, we are looking for you. Robotics experience not required!

https://www.monumental.co/jobs

Klara Inc. | OpenZFS Developer | Full-time (Contractor) | Remote | https://klarasystems.com/careers/openzfs-developer/

Klara provides open source development services with a focus on ZFS, FreeBSD, and Arm. Our mission is to advance technology through community-driven development while maintaining the ethics and creativity of open source. We help customers standardize and accelerate platforms built on ZFS by combining internal expertise with active participation in the community.

We are excited to share that we are looking to expand our OpenZFS team with an additional full-time Developer.

Our ZFS developer team works directly on OpenZFS for customers and with upstream to add features, investigating performance issues, and resolve complex bugs. Recently our team has upstreamed Fast Dedup, critical fixes for ZFS native encryption, improvements to gang block allocation, and has even more out for review (the new AnyRAID feature).

The ideal candidate will have experience working with ZFS or other Open Source projects in the kernel.

If you are interested in joining our team please contact us at [email protected] or apply through the form here: https://klarasystems.com/careers/openzfs-developer/

OneCrew | Multiple Roles | ONSITE / HYBRID | San Francisco, CA

OneCrew is the leading unified platform helping paving contractors estimate accurately, manage crews effectively, and track profitability in real-time. We eliminate the costly mistakes and wasted time that come from juggling multiple disconnected systems—giving contractors a single source of truth to run their entire operation.

We recently closed our Series A and are looking for highly motivated individuals to own their domain and accelerate our growth.

  - Engineering Manager
  - 3x Software Engineers (Fullstack, Frontend, Backend)
  - Product Manager
  - Growth

ELI Beamlines (ELI ERIC) | Dolní Břežany (Prague), Czech Republic | Onsite (with HO) | Full‑time

We operate one of the world’s leading high‑power laser research facilities (up to 10 PW) and support an international user community. We’re hiring:

• Director for Technology Lead the Technology Division (laser beam transport, instrumentation, engineering services, control systems, data infrastructure). Set the technical roadmap, grow teams, and ensure reliability and integration across the facility. Apply: https://www.eli-beams.eu/careers/director-for-technology/

• SW Control Systems Developer Join the Controls Hardware Integration team. Build and maintain device control & data‑acquisition for lasers/beamlines (EPICS). Write IOCs/services in C/C++/Python, integrate hardware, and collaborate with scientists on Linux. Apply: https://www.eli-beams.eu/careers/sw-control-systems-develope...

• Web Developer for Data Visualization Build interactive tools and UIs that help researchers visualize experiment data and plan setups (from dashboards to 3D/WebGL). Work across Python backends & modern JS frontends; design clean APIs; familiarity with Jupyter/three.js/D3 a plus. Apply: https://www.eli-beams.eu/careers/web-developer-for-data-visu...

• Safety Systems Engineer (PLC / Interlocks) Own the PLC‑based Personal Safety Interlock (PSI): define state logic, supervise installation/upgrades with suppliers, commission new areas, and keep documentation, testing and availability tight. Apply: https://www.eli-beams.eu/careers/safety-systems-engineer-152...

How we hire: CV → HR pre‑screen → interviews (in‑person or Webex). Questions? Email HR: [email protected] Or me with technical ones [email protected]

About us: ~350 people from 38+ countries; easy public‑transport commute from Prague. Keywords: EPICS, Python, Linux, PLC/Safety, JavaScript/TypeScript, Git.

Sumble is the newco from the founders of Kaggle. We are hiring software engineers, data engineers, machine learning/ai engineers, a product manager and a designer. Can view our roles and apply here: https://apply.workable.com/sumble-inc/

As background, we are building a knowledge graph from web data with a first focus on data for go-to-market teams. We use sources like job posts and resume data to identify things like org structure, tech stack, and key projects (e.g., GenAI initiatives, cloud migrations). Our product already has strong product-market fit, early revenue, and happy customers — and now we’re ready to accelerate.

Our long-term vision is to become the primary destination for accessing high-quality web data. Try the product at sumble.com.

We are a team of 15, including 10 engineers with experience at companies such as Google, Meta, Stack Overflow, and Kaggle.

Tandem Health | Senior/Staff Software Engineers | On-site in Stockholm, Sweden | Full time

At Tandem Health we're building a clinician copilot to allow clinicians to focus on care rather than administration. We’re building, launching and iterating quickly, and already have >2000 organizations using our product.

Our core product listens in to the patient-clinician encounter to generate medical records, allowing clinicians to save 5-10 minutes per patient. No longer do clinicians have to catch up on administration after hours. Some even tell us that their partners notice they're much more relaxed after starting to use our product, and we couldn't be happier :)

We just raised a $50M Series A and are now expanding our Stockholm team with exceptional engineers! We use Python (backend), TypeScript/React (frontend) and C# (Windows app) and our infrastructure runs on Kubernetes in Azure. We're scaling rapidly in terms of # of users and are especially keen to talk to seasoned backend, data and infrastructure engineers.

Even if we don’t have a role out for your specific skill set, we’d love to talk! Our tech team is small but growing and you’ll have an outsized impact on an important problem.

More info at https://www.tandemhealth.ai/recruitment

Feel free to reach out to [email protected] if you have any questions

Oneleet (YC S22) | Multiple Roles | US & NATO Countries | Remote | Full-time

Oneleet is an all-in-one cybersecurity startup that has built its own Attack Surface Monitoring (ASM), Code Scanner, Device Monitoring, and Compliance Platform. We are growing at an unprecedented pace and working on some very exciting projects.

What we're looking for:

Strong problem solvers who can work independently in a remote environment - Security-minded professionals passionate about building robust, scalable systems - Comfortable working during Eastern Time

Tech stack: Go, TypeScript, React, Kubernetes

Open roles:

* Software Engineer, Backend

* Software Engineer, Cloud Security Posture Management

* Application Software Engineer, Endpoint Security

* Security Program Manager (EU Timezone)

* Technical Sales (must have background in Computer Science or Cybersecurity)

* Invoicing Coordinator

We offer:

- Competitive salary - Equity in a fast growing cybersecurity startup - 100% remote work - Company offsites every quarter (past offsites have been in The Netherlands and Italy)

If you're interested in joining our team, please reach out to samuel<at>oneleet<dot>com with the subject line "HN: <Job Title>".

Alternatively, you can also apply at https://www.ycombinator.com/companies/oneleet/jobs

Radar Labs | Software Engineers (SRE, data platform, backend, full-stack, mobile) | Remote (US), NYC | Full Time | https://radar.com

- Radar Labs is the geo-location dev tool. - Doing 1B+ API calls per day - Our main languages are Rust and TypeScript, we also use mobile and offline pipeline languages (Python, Scala, and Terraform).

- We're based in NYC with our HQ in Union Square and remote friendly (US).

Interesting things we're working on:

- HorizonDB, our Geospatial database written in Rust

- Precise indoor location more accurate than iOS and Android leveraging Ultra-Wideband and other sensors and ML.

- Extracting raw map data from satellite maps and the web leveraging ML and AI

- Anomaly detection to identify spoofed locations

- Mobile infrastructure that automatically configures itself optimizing battery-life and location accuracy for different use-cases over time

- Multi-Region AWS K8s deployment, 99.99%+ availability

- Frontend tools to visualize and debug location data at scale

Check out our jobs page here: https://radar.com/jobs#jobs If you have any questions, feel free to reply here or you can e-mail me at [email protected]

Composio | Senior Backend Engineers + Product Engineers (Frontend + SDKs) | Full-Time | In Office (SF and Bengaluru, India)

Hi HN, we’re building https://composio.dev — the fastest way for AI agents and developers to take action across apps like GitHub, Gmail, Slack, and more. Our SDKs (TypeScript + Python) and APIs let developers connect and execute tools in just a few lines of code.

We’re a small, fast-moving team obsessed with developer experience. Our stack is TypeScript-heavy: backend in TS/Go/Python, frontend in React/Next.js, SDKs in TS/Python. You’ll work across product and engineering to define APIs, craft abstractions, and ship features used by thousands of developers.

We’re early stage, small team and looking for engineers who want ownership and impact.

Feel free to reach out to me with your resume and links of your work: [email protected]

Dash0 | Multiple roles | FULLY REMOTE | Full-time | Salary + equity

Dash0 is a fast-growing, venture-backed startup on a mission to make observability radically easier for every developer.

We fully embrace OpenTelemetry, Prometheus, and open standards, and our “welcome present” to the OpenTelemetry community, OTelBin, a free tool for editing, visualization and validation of OpenTelemetry collector configurations, is being extremely well received by the community.

We’re currently hiring in multiple roles across engineering, design, and product:

* Senior Product Engineer – Backend (Remote EU)

* Senior Product Engineer – Kubernetes Operator (Remote EU)

* Senior Product Designer – Observability (Remote EU)

* Senior Technical Writer (Remote)

Apply here: https://careers.dash0.com/

Spacelift | Remote (Europe) | Full-time | Senior Software Engineer | $80k-$110k+ (can go higher)

We're a VC-funded startup (recently raised $51M Series C) building an infrastructure orchestrator and collaborative management platform for Infrastructure-as-Code – from OpenTofu, Terraform, Terragrunt, CloudFormation, Pulumi, Kubernetes, to Ansible.

On the backend we're using 100% Go with AWS primitives. We're looking for backend developers who like doing DevOps'y stuff sometimes (because in a way it's the spirit of our company), or have experience with the cloud native ecosystem. Ideally you'd have experience working with an IaC tool, i.e. Terraform, Pulumi, Ansible, CloudFormation, Kubernetes, or SaltStack.

Overall we have a deeply technical product, trying to build something customers love to use, and have a lot of happy and satisfied customers. We promise interesting work, the ability to open source parts of the project which don't give us a business advantage, as well as healthy working hours.

If that sounds like fun to you, please apply at https://careers.spacelift.io/jobs/3006934-software-engineer-...

You can find out more about the product we're building at https://spacelift.io and also see our engineering blog for a few technical blog posts of ours: https://spacelift.io/blog/engineering

Additionally, we're hiring for a new product we're building, Flows[0]. Mostly the same requirements and tech stack, without the devops bits. If you'd like to apply specifically for that, just mention "new product" in the cover letter field.

[0]: https://events.spacelift.io/devops-next

Better Stack | https://betterstack.com/ | /^(Full-?stack|Backend) Engineer$/i | Europe remote in UTC ± 3h

We are software builders at :heart:

CEO is a software engineer, COO is a software engineer and you guessed it; CTO is an engineer, too. We are engineers, making the tools we always wanted. If you love building amazing software, you're at the right address.

We are looking for software engineers who, if given enough time, could build Better Stack on their own = looking for Full-Stack/Product Engineer/Generalist to help us create high-quality software with exceptional UX – end to end.

Apply at https://betterstack.com/careers/fullstack-engineer

How we operate: - https://betterstack.com/careers - https://betterstack.com/careers/engineering - https://juraj.blog

Duranta | https://www.getduranta.com/ | Seattle, WA | ONSITE | Full-time

Roles: Computer Vision Engineer

We are building software to help lawn care professionals & landscapers design, sell and maintain beautiful spaces. Millions of acres a year are converted into urban dwelling spaces, and we want to help make them as beautiful and as ecologically friendly as possible.

Duranta was founded a little more than a year ago. We are well funded and are expanding our team. Join us, as our second CV/ML engineer and help lead Duranta's computer vision efforts. You'll work on foundational models for aerial imagery understanding, using one of the largest aerial datasets ever assembled, and: Collaborate with the founders and a world-class CV/ML advisor to push the limits of aerial image understanding Architect scalable training & inference pipelines Build and refine models for fine-grained semantic and instance segmentation Drive experimentation and infrastructure for rapid iteration Help define our CV roadmap—from model architecture to dataset strategy to active learning

Stack: Python, PyTorch, Mask2Former, SwinV2, AWS, W&B

If you're interested in working with us, please apply online. Mention you're from HN and let us know why Duranta is of interest and what you've been working on lately.

Please apply on: https://jobs.lever.co/getduranta

ShieldAI | Web & Infrastructure Engineer | Full-time | Remote (US) or San Diego, CA with occasional travel

ShieldAI's Hivemind Special Project is hiring a Staff to Principal-level Infrastructure & Web Applications Engineer. We're a small team entirely comprised of L5-L8 ICs, working to bring seamless robotic behavior and coordination development from a sci-fi concept into reality. Our team work on a collection of long-term initiatives, demos, spike/proof of concepts, and assists to support Hivemind Product and Hivemind Solutions. LLM/AI applications for development acceleration represent a significant portion of our focus.

For this role, we are looking for someone deeply versed into Web Application and Infrastructure development. In particular TypeScript, bundlers, isomorphic development strategies, Web semantics, CSS/modules, browser performance optimization, protocols etc. If you have built custom webpack loaders, an SSR framework of FRP renderer from scratch, done packet level processing, or frame-rate optimizations in React, and have strong opinions about functional development and infrastructure please reach out!

Full Job posting: https://jobs.lever.co/shieldai/55c5676a-8b67-4379-84a8-58f59... If you are interested please contact me at [sp_hiring_sep2025 AT shield.ai] or apply directly on the job posting.

Common Prefix | Software Engineers / Auditors | Greece | Remote | Full-time

Common Prefix is a science-first blockchain consulting company. Our vision is to make blockchains usable for mainstream users and everyday people – paying at the supermarket, remittances, moving money across borders, saving, investing – and solving the real problems of usability, scalability, and interoperability that come with it. We're a 30-person team, half scientists (cryptographer PhDs, post-docs, and professors) from renowned universities, half engineers with long web2 experience. A lot of our field is broken and we're trying to make a small contribution in fixing it, by introducing provable security and proper engineering practices across the board.

What we're looking for:

Software engineers who can solve problems, are smart, get things done, and enjoy working on the bleeding edge, learning about cryptography, and working from first-principles.

Auditors who can write and read code, especially low-level cryptographic implementation code (zero knowledge verifiers, signature schemes, etc), consensus (PoW, PoS), or smart contracts (everything DeFi).

Tech stack: Doesn't matter, we'll teach you. But we work mostly with Rust.

Open roles:

* Software Engineer, https://commonprefix.notion.site/sw-folk

* Auditor, https://commonprefix.notion.site/auditing-folk

We offer:

- $80,000–$160,000 / year cash - Local from Athens, Greece, or remote, preferably in Europe - Conference participation in exciting scientific and engineering venues, 2-3 times per year - The opportunity to work and learn from world-class scientists from major universities in the field of blockchains, cryptography, and consensus

If you're interested in joining our team, please reach out to careers<at>commonprefix<dot>com with the subject line "HN: <Job Title>".

Saris AI | Full-Stack + ML Engineers | Full-Time | Onsite / Remote | Montreal, Canada

Hi HN, we are an YC alum founding team rethinking back-office workflows for banks and credit unions. We're tackling a $100 billion problem with the kind of automation problems that require long-context reasoning, tool orchestration across many critical systems, and strict compliance loops: the ones without known answers.

We've shipped real agents that handle real customer workflows in production. With a growing customer base and live deployments, we're scaling up fast and looking for deeply technical builders who want to have outsized impact early.

See more about the role & apply here: https://www.linkedin.com/jobs/view/4281413302

Uncountable | NY, SF, London & Munich (In-Person) | Full-Stack Engineering

https://www.uncountable.com/hiring/hn

Uncountable accelerates R&D for industrial scientists across leading materials, chemicals, and life sciences organizations. With our SaaS solution, our customers get better products to the market in half the time. Uncountable was founded by MIT and Stanford engineers and has been profitable since 2016. Our team has grown from 50 to 100 over the last two years.

Full-Stack Engineers | $120k - $220k + Equity

---> Uncountable is looking for engineers who can spearhead the development of the Uncountable Web Platform. The position is heavily product-driven and comes with challenges across the stack.

--> Summer internships and working student positions are also available.

Learn more: https://www.uncountable.com/hiring/hn

Uncountable is hiring in New York City, San Francisco, London, and Munich.

Contact our CTO directly at [email protected]

Base Power | Onsite | Austin | Full-time | https://www.basepowercompany.com/careers At Base we're rebuilding the nation's power grid. We build and manufacture power systems, deploy them across the grid, and build the algs, ingestion and commanding platforms that operate the fleet in response to real-time grid conditions. Our team is made up of engineers from top infrastructure and energy companies (Apple, Anduril, Starlink, etc) and we have several years of runway from top firms (a16z, Valor, Thrive, Addition). We are looking for: - platform engineers - firmware & controls engineers - embedded software engineers

Sampling of exciting upcoming problems include: - Home load prediction algorithms - Resilient factory execution software platform - Automated hardware-in-the-loop (HIL) test system

Stellar Science | Hybrid (USA) Albuquerque NM, Washington DC (Tysons VA), Dayton OH | Full time, interns/co-ops | U.S. citizenship required | https://www.stellarscience.com

Company: We're a small scientific software development company that develops custom scientific and engineering analysis applications in domains including: space situational awareness (monitoring the locations, health and status of on-orbit satellites), image simulation, high power microwave systems, modeling and simulation, laser systems modeling, AI/ML including physics-informed neural networks (PINN), human body thermoregulation, computer vision and image processing, high performance computing (HPC), computer aided design (CAD), and more. All exciting applications and no CRUD. We emphasize high quality code and lightweight processes that free software engineers to be productive.

Experience: Other than interns, we currently require a Bachelors degree in physics, engineering, math, computer science, or a related field, plus preferably 3+ years of work experience or a Masters or PhD in lieu of work experience. (Roughly 30% of our staff have PhDs.)

Technologies: Mostly C++23, Qt 6.9, CMake, git, OpenGL, CUDA, Boost, Jenkins. Windows and Linux, msvc/gcc/clang/clangcl. AI/ML and other projects use Python, some projects use Java or Javascript/Typescript/React.

Apply online at https://www.stellarscience.com/careers/.

Konvu | https://konvu.com/ | Software Engineer | FULLTIME | ONSITE | Paris, France

At Konvu, we’re on a mission to make security invisible. As we move towards a future dominated by code automatically generated, tested, and deployed by AIs, we need a new paradigm for application security. Vulnerabilities must be automatically detected, prioritized, and remediated.

Behind Konvu are founders with deep roots in the security industry. As early employees at Sqreen YC W18, a notable security startup acquired by Datadog, we have firsthand experience in driving security solutions from concept to global impact.

We’re looking for:

* Product Engineer https://jobs.ashbyhq.com/konvu/be7be978-08be-4672-a9e5-a559e...

* Product Engineer (AI Agents) https://jobs.ashbyhq.com/konvu/be028b43-a7a7-4f0a-b968-320dd...

* Founder Associate https://jobs.ashbyhq.com/konvu/36074d15-1958-48e7-8fa4-96fd7...

Read more about how we're building Konvu the YC-way: https://konvu.com/blog/yc-culture

Kredit | .NET Engineer Roles | Remote (US) | Full-time Kredit (trykredit.com) is on a mission to resolve debt better. We provide tools to regular people to help them get the out of financial hardship, as well as provide tools for businesses to manage their processes. We are small (6 person dev team) and growing. Our stack: .NET Core, C#, PostgreSQL, Mediatr, CQRS, Events, Angular, GCP, Kubernetes, Terraform and much more.

We are a Event/CQRS stack and are looking for Engineers that fit that experience in this area.

If this sounds interesting to you, please reach out to [email protected]

Count | Senior Software Engineer | REMOTE within UK/Europe | Full-time | https://count.co | £100-140k + Equity

Count is like Jupyter, Tableau and Miro combined in one tool. Some of the world's leading data teams use it for everything from iterating data models and performing in-depth analyses to creating process flow maps of their entire business.

We're a small team looking for experienced software engineers who are interested in tackling deep technical challenges in the data analytics space.

For the best possible user experience, we have developed various technologies in-house, including a custom WebGL rendering engine, our own data visualization library, and a reactive SQL/Python notebook and database query framework.

Example projects: leveraging agentic workflows in data exploration, accelerating rendering using quadtree tiling, extending interactivity and customizability of visualizations, developing serverless frameworks for executing database queries at high concurrency.

Our tech stack: TypeScript, Python, Node, WebAssembly, WebGL, Apache Arrow/Parquet, DuckDB, Kubernetes, React.

For more details and to apply: https://jobs.ashbyhq.com/count

Komodo Health | Applied AI Engineer | Full-Time | $200-$253k + equity... | SF/NY Once-a-month-few-days / Remote US. Can sponsor.

Healthcare in the U.S. is a mess. Komodo Health is fixing that—with data. We’ve mapped the patient journey across the country to build the most complete picture of disease burden and treatment gaps. Our customers are pharma, payers, and health systems who actually want to do something meaningful with that information.

We have an exciting product, marmot, that is AI-native, both in the interface as well as in development, and want to carefully grow high productivity teams around this offering. AI integrated with Komodo's data is giving some of the most unique, real world insights any of us has seen come out of the new LLM era. Our product was just featured on Times Sqaure too! https://www.linkedin.com/posts/komodo-health_last-week-our-d...

We are looking for highly independent individuals, who can work in a new, small, but empowered team. What will you be bringing? - Proven experience working on Agentic systems that solve real problems OR Some evidence you have the "instinct" Andrew Ng mentions as the differentiators of successful Agent builders. We also take full ownership of the product, so experience+readiness for fullstack development is a must. Core ML experience is not required and for this position, not relevant at all. The new LLM/Agent era is... different.

Perks will include annual conference trip, periodic travel to SF/NY for on-site, Executive Coaching, etc.

If this post sounds exciting, please apply at https://job-boards.greenhouse.io/komodohealth/jobs/806961600... (mention HN as the source). Please note, we can only consider applicants who are already in the US.

If you wish, please also email me at [email protected] with an example of how you have figured out that instinct I mention above.

Langdock (YC S23) | Product Engineers (Full-stack), Infrastructure Engineers, AI Associates | Berlin, Germany ONSITE | https://langdock.com

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We're Langdock, and we've built the LLM platform that 1,300+ companies trust to power AI features for 100,000+ users. After hitting $9M ARR with 10x year-over-year growth, we're expanding our Berlin team to shape the next chapter of conversational AI.

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Product Engineer (Full-stack) | €66K – €102K | Equity | €10K – €30K Bonus

Build product features from conception to deployment, collaborating closely with our CPO and working across the entire tech stack to deliver AI-powered features that drive enterprise adoption.

Stack: NextJS, React, Prisma, Postgres, Redis

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Infrastructure Engineer | €66K – €102K | Equity | €10K – €30K Bonus

Contribute to our deployment infrastructure and lead integrations with customer cloud environments. You’ll work hands-on with the latest cloud and container technologies, ensuring our platform runs reliably and securely for some of Europe’s top enterprises

Stack: Terraform, Azure, AWS, GCP, OpenShift

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AI Associate | €66K – €75K | Equity | €10K – €15K Bonus

Three-month rotational program with a pathway to high-impact commercial roles. You’ll join a cohort of technical, customer-facing talent who build deep product expertise and commercial acumen from day one.

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Check out our jobs page here: https://jobs.ashbyhq.com/langdock

FunnelStory | Principal Architect (Go) | REMOTE (India) | Bengaluru | Full-Time | 55-85 LPA | https://funnelstory.ai

I'm Preetam, co-founder and chief architect of FunnelStory. We're looking for a back-end engineer with a strong Go background to join our team.

FunnelStory is an AI-first customer superintelligence platform. We're a small (<20 people), fast-growing, VC-backed, early-stage startup, and we're gaining exciting traction with enterprise customers. We're looking for an architect/engineer for a team that's building next-generation AI platforms using Go.

This is a great fit if you have:

* Deep expertise in Go.

* A strong architectural background, with experience designing and scaling complex systems.

* Expertise with relational databases (PostgreSQL) and SQL

* Excitement about taking a high-impact, independent role in an early-stage environment, helping to mentor and uplift the team.

Who we're looking for:

* 8+ years experience in Go, SQL, AWS

* Bias to action, ability to execute independently

* Strong architectural and problem-solving skills

* Ability to communicate complex ideas simply

More details + apply: https://wellfound.com/l/2Bn5eQ

Interested? Email me at preetam @ funnelstory.ai with "HN" in the subject.

Humaans (YC W21) | Engineering Leads, Senior Full-Stack Engineers | London (Hybrid, 3 days/week) | Full-time | https://humaans.io/

Hello! Co-founder of Humaans here. We’re building a best in class HR platform that automates people operations end-to-end for globally scaling companies.

What you’ll work on:

* Agentic AI for end to end automation and AI functionality all over the product

* Modern client rich UIs including workflow builders, drag-and-drop task managers, collaborative spreadsheets

* Realtime systems via WebSockets, Feathers.js, zero sync engine

* Scaling our data and AI architecture to fly for customers with 1,000s of employees

Why we like it here:

* Quality-first culture - design, performance, and DX matter

* Small, senior team with ownership from product definition to release

* Backed by great partners (YC and execs from Slack, Shopify, Figma, LinkedIn, Stripe, Intercom, Notion, etc.)

Our stack:

* TypeScript, React, Node.js, Postgres, Redis

* Monorepo with Turborepo, pnpm, GitHub Actions, Kube and CloudRun on GCP

Apply here: https://jobs.ashbyhq.com/humaans?utm_source=7nNGnERWLP

RevEng.AI | London, UK | Full-Time | ONSITE+PART REMOTE | https://reveng.ai

RevEng.AI is building foundational AI models to identify malicious threats and security vulnerabilities inside software. We're a seed stage startup having raised $4.25m from top tier VCs across the US and Europe. You’ll play a key role in advancing our platform pushing the boundaries of AI-driven program analysis.

We're looking to hire security engineers and security researchers with experience in program analysis, reverse engineering, vulnerability research, machine learning, and malware analysis.

* 5+ years of experience

* Masters or PhD in a relevant area for the security researcher role

* Hybrid working environment but ideally commutable to London, UK

* Solid understanding of software engineering design

* Ability to thrive in a fast-paced start-up environment

To apply or learn more, email contact[at]reveng.ai with "hn" in the subject line.

Justworks | Hybrid (US: New York City, Canada: Toronto) | Full-time | Multiple roles | https://justworks.com/careers

Justworks is helping businesses get off the ground by enabling them to focus on running their business. We solve HR issues. We’re data-driven and never stop iterating. And, we are hiring across the board! If you’d like to work in a supportive and entrepreneurial environment, are interested in building something meaningful, and having fun while doing it, we’d love to hear from you!

- Engineering Manager: https://grnh.se/yzes4b8l1us

- Senior Software Engineer: https://grnh.se/lluz9tup1us

- Software Engineer: https://grnh.se/6q95fndp1us

- Engineering Manager, Infrastructure: https://grnh.se/qa3m2hxt1us

- Senior SRE: https://grnh.se/b6es9bfa1us

- Infrastructure Engineer: https://grnh.se/qadh1e1v1us

- Group Product Manager: https://grnh.se/3jlr8o3c1us

- Product Manager: https://grnh.se/1nkz4qef1us

Howie.systems (EU VC funded) | Full-Stack (AI) Engineer | ONSITE Vienna, Austria | Full-time | Start date: ASAP

- We’re building Howie.systems, an AI platform for the architecture/engineering/construction industry. Our focus: automating knowledge extraction and retrieval from large document sets (100k+ files, multi-tenant, multi-user, with Supabase/Postgres + pgvector under the hood). We’re fully funded by international investors and are expanding our team in Vienna.

Role: We’re looking for a Full-Stack Engineer with a love for strong typing and AI.

- Must: Next.js, Supabase, very TypeScript-safe mindset

- Super plus: experience with AI frameworks (Vercel AI SDK, Mastra, LangChain, etc.)

- Should have good experience with AI Coding tools like Cursor, Cloud Code

You’ll help us scale our ingestion, RAG, and AI interaction layers into production-grade tools dealing with enterprise customers

What we offer:

- Competitive salary + equity possible Onsite in Vienna (no remote option)

- Small, hands-on team with big international backing Work on a fully modern stack (TS, Supabase, Vercel, AI frameworks)

If this sounds like you, send your CV and a cover letter to: [email protected] Please include within the cover letter, detailing your experience and why you think you would be a fit for the role

Class Central | Senior Full Stack Engineer | Remote | https://www.classcentral.com

I'm looking for a senior engineer to take ownership (from me) of Class Central's codebase and infrastructure.

We help tens of millions of learners find the best courses on any subject. Small team (6 people), profitable, independent, and around for 13+ years. No VC drama, just sustainable growth.

Stack: PHP 8+, Symfony 7+, MySQL, Elasticsearch, Google Cloud. We keep it simple and productive.

Own the full stack, help shape our product, and build pragmatic solutions for our current scale. I am looking for product-minded engineers who are focused on user experience and driven to understand the business.

I'm building a new cross-functional product team from scratch (engineering, product, design). Looking for a foundational engineer who can mentor, collaborate, and help define how we work together.

Remote-first, async, very few meetings. Real autonomy, real impact. Fair warning: being fully remote means no annual Halloween Heists.

While I don't have a formal job post up yet, if you're at that point where this feels like the right next step, I'd be happy to hear from you: [email protected]

April | https://www.tryapril.com | San Francisco /Gurgaon, India | ONSITE | Full-time

  Roles:
  1. Head of Growth (SF)
  2. Senior Software Engineer (Gurgaon, India)

Head of Growth - Own the 0→100K user journey. Build content-led growth across LinkedIn/X/TikTok, run viral B2C experiments, and craft our brand voice. We need a proven track record of growing consumer products, content creation chops, and unreasonable excitement about retention curves. Extremely competitive salary + equity + user milestone bonuses.

Senior Software Engineer - Build the core backend for our AI assistant. 2-6 years of experience, TypeScript/Python, with consumer product background preferred. Work directly with founders on architecture decisions. Must work from the office. Competitive salary + early equity + quarterly performance hikes.

If you're interested, send your profile to [email protected]

Zetier | Multiple US locations (VA, PA, FL, TX, CA, NY) | ONSITE | Full-Time

Zetier develops real-world tools and capabilities to secure our nation in the short- and long-term. If you’re excited to delve deep into low-level systems, exploit dev, and more alongside a group of passionate hackers, then we’d love to hear from you.

Open-sourcing our work as much as possible is integral to Zetier and what we stand for. As folks who learned to hack on platforms like Linux, we aim to give back to the OSS community. Not only do we encourage our engineers to contribute, but we go a step further, adding monetary incentives to do so.

We’re looking to find the right people for a range of roles, including:

+ Vulnerability Researcher

+ Android Security Engineer

+ CNO Embedded Engineer

+ CNO Software Engineer

+ IT Security Engineer

+ Senior Technical Lead

+ Business Developer

All open positions: https://zetier.breezy.hr/

Our approach and benefits: https://zetier.com/careers/

Different skill set? Drop us a line at [email protected]

*Maiven | Full-Stack Engineer & Energy Modeling Engineer | Remote (US) | Full-Time*

Maiven is the software platform automating home decarbonization. We’re a small, mission-driven team punching way above our weight: we have large utility customers, contracts in multiple states, and a growing pipeline of programs launching later this year. We’re venture backed and moving fast.

We’re hiring two engineers:

- *Full-Stack Engineer* – NestJS, React, Tailwind, TypeScript, Python, Postgres, AWS, Lambdas. Someone who cares deeply about UX and moving fast while delighting the user. - *Energy Modeling Engineer* – Python, pandas, AWS, modeling frameworks (ResStock, EnergyPlus, etc.). Experience with energy programs or building science is a huge plus.

Looking for builders who want real ownership, thrive in early-stage startups, and move with urgency and care.

More: https://www.askmaiven.com

To apply: email [email protected] with a resume and your links.

Freetrade | London (ONSITE) | Full-time | https://freetrade.io | £75k-£140k

Freetrade is a commission-free investing app used by over 1 million people in the UK. Our team is expanding, and we’re seeking software engineers to evolve and scale our core investing platform. In this role, you will be instrumental in building and maintaining reliable and trustworthy systems for trade execution, clearing and settlement, asset servicing, and internal operational tools. You will also play a key role in shaping our technical direction and mentoring other engineers as our team grows.

Tech we use: TypeScript, Node.js, Postgres, and GCP

Note: We are three days in the office, located just around the corner from Old Street. We don’t sponsor visas at the moment.

We are hiring across the board in engineering, data, people, marketing, risk & compliance and finance. See all of our opportunities here:

https://freetrade.io/careers

PlantingSpace | Full-time | Remote (EU time zone) + Quarterly Meet-ups | https://planting.space

We’re building an AI system for analysts and scientists, based on a fundamentally new approach to reasoning and knowledge representation. Our approach differs from LLMs in that we compose algorithms symbolically to represent complex knowledge, and perform probabilistic computations. This enables the AI-driven application of statistical models to different problems, while providing the user with a verifiable reasoning path, and an assessment of the uncertainty in each answer. We are developing applications for analysis and research in domains such as Finance, Strategy Consulting, Engineering, Material Sciences, and more.

Ready to push the frontier of automated structured reasoning? Check out our current openings for:

* Program Synthesis Engineer

* Product Software Engineer

* Senior Product Manager

See detailed role info, and apply: https://planting.space/joinus/

Questions welcome! Get in touch: [email protected]

OpenRent | London, UK | Full-Time | ONSITE+PART REMOTE | https://www.openrent.co.uk

What sucked the last time you rented a house or flat? Come and fix it.

OpenRent is a force for good in an industry tarnished by rip-off agencies. Enabled by an unrelenting focus on technology, we now let more properties than any agency in the UK. In the last 12m we let over £50 billion worth of property, to over 7 million registered users, without ever charging any admin fees.

You'll be working on solving every aspect of the rental journey, from models to predict the right price of a property, to building the future of property management, all to help tenants find their dream home, and landlords their ideal tenant.

We're VC backed, profitable, and have plenty of ambition to maintain our fast growth in this absolutely massive market.

Roles currently available:

- Senior UX/UI Developer | Equity | 100k+ (based on experience) + quarterly bonus

All roles visible here: https://www.openrent.co.uk/jobs