xAI (Yes, we just got acquired by SpaceX, no, I can't talk about it)

We're the truth-seeking AI (Grok) that accelerates human scientific discovery and deepens our collective grasp of reality.

We're looking for the very best technical talent globally (in-office) - Palo Alto or SF / Seattle / Memphis / NYC / London / Dublin / Tokyo / Dubai / Singapore

292 jobs are currently open - https://job-boards.greenhouse.io/xai

Software Engineers - We're flexible, but think Rust / C++ / Python / Typescript / React

Infra/SRE - k8s / Terraform / ArgoCD / Go

Grok Engineers - machine learning fundamentals, including model evaluation, training and fine-tuning / Python / Typescript

If you're an Engineer and not sure what the best fit is, try applying for one of our 'Exceptional' roles and we'll assess where we think you'll fit: London - https://job-boards.greenhouse.io/xai/jobs/4956070007 Palo Alto - https://job-boards.greenhouse.io/xai/jobs/4956028007

Last step - if you want some assistance, email me at mspiers@x.ai - Include 'hackernews' in subject line and please attach your CV.

Curiosity | Full-Stack Developer (C# / Java / Python) | Munich, Germany | Full-time | Onsite only

Curiosity (https://curiosity.ai, Munich) builds an AI-enabled graph database that helps industrial companies and make sense of complex, fragmented data by connecting documents, systems, and knowledge across the enterprise.

We’re hiring a full-stack developer (new grads welcome), local to Munich only.

You’ll build performant production software and design solutions for our customers. C# preferred, Java or Python ok. Full-stack role ideally with web frontend experience. Background in databases, text processing, or search engines is a plus.

We’re looking for someone hands-on and outgoing who is comfortable interacting with customers and partners.

If that sounds interesting, get in touch at jobs@curiosity.ai

Verge Genomics (YC S15) | Multiple roles: Computational Biologists (all levels), Principal Full-stack Engineer, Senior Data Engineer, Staff AI Scientist (Foundation Models) | REMOTE (US) | Full-time

Verge is transforming drug discovery by using artificial intelligence and proprietary human data to solve the biggest driver of rising drug costs: high clinical failure rates. To achieve this, we have built one of the field’s largest corpuses of multi-modal patient molecular and clinical data, sourced directly from human tissue. Our team of engineers, neuroscientists, and biologists have so far delivered two drugs to clinic, discovered 282 new targets, and signed commercial partnerships worth in excess of $1.6B with Eli Lily and AstraZeneca.

We are hiring across engineering and computational biology. All roles are fully remote, but we are only considering applicants based in the United States -- with extant permission to work here (sorry, no visa sponsorships right now).

See our jobs: https://jobs.ashbyhq.com/verge-genomics

Read about our values: https://sugary-artichoke-03e.notion.site/A-Primer-on-Verge-C...

Freeform (http://freeform.co ) | Software Engineers | Full-time | Onsite | Hawthorne, CA (Los Angeles County)

Freeform is deploying metal 3D printing factories at global scale and setting a new frontier in manufacturing. With AI, GPUs, and FPGAs working in tandem, our system monitors and corrects every microsecond of the process, delivering a level of precision, speed, and quality that’s never been possible—until now. This isn’t just an improvement; it’s a leap forward in how complex metal parts are made, with the ability to revolutionize industries like aerospace, defense, automotive, energy, and beyond. We are backed by top VCs including NVIDIA’s NVentures, Founders Fund, and Threshold Ventures.

It’s a small, tight-knit team and you’d have the opportunity to own significant and impactful greenfield projects throughout the entire development lifecycle and much more. Our software team comes from the likes of Google, SpaceX, and Apple, and believe in taking a first principles approach to solving hard problems.

A glimpse into our software landscape - https://youtu.be/nFWQArUkd5I?si=mP17qdKbxvf8qpZN

Our feature in TechCrunch! https://techcrunch.com/2024/10/22/ex-spacex-engineers-land-1...

+ Senior Software Engineer, Factory Software C++ (Skyfall) - https://grnh.se/ddgoq9yh3us

+ Senior Software Engineer (Embedded) - https://grnh.se/5eerse413us

+ Senior Software Engineer (Edge Data & Telemetry) - https://grnh.se/j8jyvaj03us

+ Software Engineer (Edge Data & Telemetry) - https://grnh.se/9z8omwl13us

Category Labs | https://www.category.xyz/ | Remote and NYC | Full Time | $200K USD+

Category Labs (formerly known as Monad Labs) is a team of systems engineers and researchers on a mission to design and build at the frontier of decentralized technology. We strive to design and build step-function improvements over existing blockchain solutions. After raising $225M in series A funding, led by Paradigm, we are growing our team.

Technical Program Manager: https://jobs.ashbyhq.com/category-labs/bdfe89a6-83f6-4ab3-b6...

Senior SWE, Compiler: https://jobs.ashbyhq.com/category-labs/e5c34899-cea1-4d25-be...

Smart Contract Engineer (Solidity): https://jobs.ashbyhq.com/category-labs/776ce314-aa12-471b-92...

Senior SWE (Rust, C/C++): https://jobs.ashbyhq.com/category-labs/45f674b2-d904-482e-a5...

Senior Researcher, Systems: https://jobs.ashbyhq.com/category-labs/015934c5-66e5-4042-94...

Upway | Software Engineers (All levels), Senior Product Designer, Senior Product Managers | Full-time | Paris (ONSITE)

We’re building the biggest second-hand bike shop in the world.

Upway is the leading marketplace for refurbished e-bikes across Europe and the United States.

In 3 years, we grew from 0 to $200M GMV. The tech team grew from a small senior core to ~12 engineers in 2025, and we plan to grow to ~30 engineers in 2026. We also raised a $60M Series C at the end of last year to support the next phase of the company.

This is not a SaaS. We operate warehouses, handle real inventory, and build software that connects logistics, product, and marketplace dynamics at scale.

We’re looking for engineers and product people who like tech as much as business, people who want ownership, enjoy making product and business trade-offs, and care about outcomes, not just systems.

We work with a Shape Up–inspired methodology that gives teams real ownership: shaping problems, building solutions, shipping, and learning from real-world impact.

Stack: TypeScript | NestJS | React | Shopify | PostgreSQL | GCP

Why it’s a great time to join:

- The organization is switching gears: bigger ambitions, broader scope, more responsibility.

- The challenges are growing with the team: product, marketplace, and operational complexity.

- High ownership environment where engineers influence technical and business decisions.

- Paris on purpose: at our current pace, working in person is a real advantage.

Learn more:

- Tech & Product subjects we’re working on: https://like-piper-15f.notion.site/tech

- Open roles: https://careers.upway.shop/

- Contact our tech recruiter: https://www.linkedin.com/in/maeg-horeau-28445b72/

Kyber | Low-level Developers and Sales | Paris area (hybrid) and Remote in Europe | Full-time | kyber.media Kyber is an open-source SDK and platform to control remote machines, from Remote Desktop to Robots Teleoperation/Teleobservation. Kyber is a multi-stream and multi-actuator transport in extremely-low latency, over Quic; it encloses the server, the client and the protocol. One could use Kyber to control robots, drones, desktop, servers in the cloud or just remote rendering of interactive 3D programs. Kyber is done for Remote RealTime, where every millisecond matters. Kyber is developed by engineers from the VLC and FFmpeg community, and we code in Rust, in C and in assembly. We have some development in Go too. We're a quite technical team, but cool to work with. Contact: jobs -- at -- kyber.media (subject: “HN job”)

BitRipple | USA | Full Time | Remote - Prefer domestic USA but open to Non-Restricted Countries

We are hiring two Developer positions: - Senior Software Engineer: Network layer communication optimizations - Senior Software Engineer: GPU porting / RDMA / NCCL / NIXL layer development

We are a deep-tech company building the next generation network communication layer for AI, squeezing out GPU idle time during LLM training with accelerated RDMA communication across clusters. If you love deep systems work and high-performance networking, you will fit right in.

We also service many other networking related industries like mobility, satellite, aerospace, atmospheric optical, VPN, SD-WAN and defense.

- What you’ll do - Design and implement high-throughput, low-latency transport and flow-control logic (think TCP/QUIC/UDP, congestion control, pacing) but next level. Optimize end-to-end performance (CPU/GPU/IO), and ship results that move real workloads.

- What you bring - Proficient in C, C++, Rust Strong grasp of networking transport protocols & flow control concepts. Solid math foundation. You understand memory management, concurrency, throughput and efficiency at scale.

- Nice to have - Mobile (Android/iOS) development knowledge. GPU porting experience. NCCL / NIXL / DPDK integration experience. RDMA/RoCEv2/Infiniband/NVLink knowledge . FEC/erasure coding knowledge.

Interested? Send your resume to: work@bitripple.com You will be talking directly with: Mike Luby, CTO: https://www.linkedin.com/in/michaelluby/ or myself Scott Brown, CEO: https://www.linkedin.com/in/scott-k-brown/

SpruceID (YC W21) | REMOTE (US-Based Preferred) | Full-Time | spruceid.com

[NEW ROLE FOR EXCEPTIONAL NEW GRADS OPEN]

Spruce lets users control their data across the web. Instead of users logging into platforms, we believe platforms should request to access data vaults controlled by users.

The demand for trusted digital ID is accelerating as AI deepfakes begin to destroy most of the ways we use to verify identity today. How private or secure is it to hold your driver's license or passport up to a webcam to get a bank account? Was it ever private or secure? Stable diffusion can break so much of this already. Society will need trusted digital IDs and credentials. Our mission is to allow them to be controlled by individuals, with safeguards to prevent descents into surveillance states and checkpoint societies.

We are the main implementers of category-defining initiatives such as the digital ID program for the California DMV, and the verifiable digital credentials program in Utah. We are private sector participants in NIST's National Cyber Security of Excellence initiative for privacy-preserving digital ID.

We are hiring skilled engineers who care about making a real impact in improving public services, digital autonomy, and user privacy for the world. We work closely with public sector agencies, and have high regard for public servants. We have a strong engineering and customer-oriented culture, and are not simply a SaaS product or AI wrapper. Our roles are not for the faint of heart: you will be expected to work hard and learn a lot in this role.

Our engineers are ambitious to get outcomes for our customers and their constituents. On any given day, they may write great Rust/C#/TypeScript, deal with mainframe dumps, read policy documents, respond to technical RFIs/RFPs, manage on-prem environments, implement new NFC + Bluetooth protocols in Swift/Kotlin, create CI/CD processes that enforce W3C accessibility guidelines and i18n requirements, rewrite lost specs from disassembled binaries, figure out stablecoin payments, and design new protections for public key infrastructure. It is a team effort, and people with T-shirt shaped skills are able to collaborate and learn a ton from each other every day.

We are interested in candidates who want to be proud of the meaningful impact they make for society, even if it takes time to get right. This is not the right job for someone who wants to "join a cool new AI startup" that implodes or exits in under a year.

See our roles here: https://jobs.lever.co/sprucesystems/

StorPool | Senior Software Engineer - Storage Core (C/Linux) | Remote (UTC-1 to UTC+5) | Full-time | Multiple roles

StorPool is building the future of data storage. Our software runs at the heart of modern clouds, delivering <100µs latency, 113M+ IOPS per cluster, and 99.999% availability. We're profitable, self-funded, and our customers love us (NPS off the charts).

We're looking for a Senior Software Engineer to join our Core Storage team. You'll tackle genuinely hard problems: writing custom Linux drivers, optimizing lock-free data structures at nanosecond scale, building fault-tolerant distributed algorithms, and debugging issues that go all the way down to kernel internals. This isn't CRUD work - it's systems programming at its most challenging.

Competitive salary, fully remote, meaningful time off, and a yearly education budget to keep learning.

If you get excited about shaving microseconds off I/O paths and building infrastructure that simply doesn't break, we should talk.

Apply here: https://storpool.com/force/senior-software-engineer-storage-...

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: Except for interns, we currently require a Bachelors degree in physics, engineering, math, computer science, or a related field. Masters or PhD is a plus. (Roughly 25% of our staff have PhDs.)

Technologies: Lots of C++23, Qt 6.9, CMake, git, OpenGL, CUDA, Boost, Jenkins. Windows and Linux, msvc/gcc/clang/clangcl. AI/ML and analysis projects use Python and C++. Web projects use Java and Typescript/React.

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

SIG | Multiple Positions | SYDNEY, AUSTRALIA | Visa Sponsorship for Experienced / PhD Candidates | On Site | https://sig.com

SIG is a global quantitative trading firm founded with an entrepreneurial mindset and a rigorous analytical approach to decision making. As one of the largest proprietary trading firms in the world we are experts in trading all listed financial products and asset classes handling millions of transactions on exchanges around the world every day.

SYDNEY:

Quantitative Systematic Trader

Quantitative Researcher

C# Developer (Post Trade Technology)

C++ Developer

Pricing Developer (C#, Python)

Python Developer

Application Support Engineer

Technical Analyst - AI

If you have not previously applied please send me your CV (email in the profile). We had few great YC hires already in the past. Contact number, visa/work rights, availability and a brief description of your current situation is useful to include.

Encube Technologies | Senior & Lead Software Engineers Onsite (Stockholm) or Remote | Full-time

Encube Technologies is building collaborative, real-time software for manufacturing. We are looking for experienced engineers to help shape the core of the product.

You will work on challenging problems at the intersection of browser-based 3D rendering, CAD compute algorithms, and real-time collaboration, with a strong focus on end users and performance. This is hands-on, product-driven engineering with significant technical depth.

What you will work on - High-performance, browser-based 3D rendering - Compute-heavy CAD and geometry algorithms - Real-time, multi-user collaboration features - Systems bridging frontend graphics and backend compute

Tech stack

Frontend - React, Next.js, TypeScript

Graphics - WebGPU, WebGL2, three.js, React Three Fiber

Backend - Python microservices with occasional C++ bindings - Kubernetes-based infrastructure

We are hiring Senior and Lead Engineers who enjoy ownership, care about product quality, and like solving difficult technical problems with real-world impact.

Apply via our website: https://www.getencube.com/we-are-encube

Please mention in your cover letter that you found Encube Technologies via Y Combinator.

Tenzir | Software Engineering & Sales | Remote (EU Timezones) | Full-time

Tenzir is building an open-core security data pipeline for the AI era. We empower defenders to collect, shape, and route security telemetry at scale. Our stack relies on C++23/26 and Apache Arrow for the core engine, with a modern TypeScript platform layer.

We are hiring for 4 key technical roles to join our distributed team (HQ in Hamburg):

- Software Engineer (Core Engine): Systems programming with C++23/26. Work on our pipeline language, query execution, database integrations, and streaming data processing with Apache Arrow.

- Software Engineer (Product): Full-stack TypeScript/Python focus. Build the control plane, platform APIs, and developer tools, AI workflows, and anything else that makes our engine accessible.

- Account Executive: Our first dedicated AE to own the full enterprise sales cycle. You'll work with complex deals in security and data infrastructure.

- Solutions Engineer: Lead POCs and post-sales implementation. You'll be the hands-on engineer ensuring customers succeed with complex data pipelines.

We are a remote-first team across European timezones. If you like solving hard data problems, we'd love to hear from you.

Apply: https://tenzir.com/company/careers

Coram.ai https://www.coram.ai | Senior / Lead Software Engineers | Sunnyvale, CA or London, UK | ONSITE

Coram AI is building an AI-powered video security platform that helps enterprises proactively detect and respond to real-world incidents. We work with large-scale video data, real-time systems, and applied computer vision.

What you’ll work on: • Backend systems handling real-time video and event data • Scalable APIs and data pipelines • Production AI/ML integrations • Building reliable, user-facing features end to end

Tech stack: • Backend: Python, Go, C++ • Infra: AWS, Terraform • Data: Postgres, streaming pipelines • Frontend exposure a plus (React), but not required

You might be a good fit if you: • Have 5+ years of professional software engineering experience • Have worked on backend or platform systems at scale • Enjoy working in small teams with high ownership

Salary - $150k–$250k USD / £90k–£130k GBP + equity

https://jobs.ashbyhq.com/coram-ai

VDX.tv (http://www.vdx.tv) | Remote Engineers & Developers | Full-time | REMOTE Established company (20+ years) looking for mature generalists to contribute remotely. You can be anywhere in the world so long as you: ● Are self-motivated and can work independently

● Driven to constantly learn and are always searching for the bigger picture

● Strong in clear thinking and written communication

● Have experience with many languages but can be effective in any language

● Appreciate that all mature software solutions accumulate technical debt and understand how to continually reduce debt and complexity

● Understand how to build highly reliable systems and be responsible for taking code to production

● Understand that code simplicity and readability are more important for long term maintainability

● Want to work on challenging problems and impactful work without being micromanaged

We're hiring across disciplines for engineers who work with Unix and have fluent written and spoken English:

● Backend Servers: Strong in C, Concurrency and Distributed Computing

● Backend Servers: Strong in Java

● Infrastructure: Strong in building infrastructure tooling to program infrastructure.

● Frontend: Strong in Javascript, Typescript, React, and advanced UI and browser applications

● Artificial Intelligence: Strong in Neural Networks, AI Workflows, AI Models.

● Product Design: Ability to spec and build out clean UIs and dashboards.

We value people who are generalists and are interested in learning, developing, and applying expertise across multiple areas.

Although our core business is in digital video advertising, we do research and development in areas such as programming languages, databases, distributed computing, infrastructure, and ai.

We are private, which gives us the freedom to explore many areas without investors and profits being the sole objective.

Full-time only. Remote only. We start out on a full-time trial contract basis for up to 3 months and use this period as an extended work interview for both sides to assess fit for long-term employment.

Please email hn.remote.jobs@vdx.tv if this sounds like the right fit for you.

Range Finance | Mclean, Virginia - On-site | Software Engineers (Senior/Staff/Principal) | Full-time https://www.range.com/public/careers

We're building the first AI wealth platform. Hiring senior+ software engineers to partner closely with our co-founders and engineering leadership team. We're a Series C company with ~90 people passionate about making wealth management better, faster, and cheaper for every household. We're open to relocating candidates. Email me (tyler at range dot com) your LinkedIn profile if you have strong technical experience and you're interested!

Stack: Claude, Node, GraphQL, React, Typescript, AWS Comp: $150 - 300k base + equity

Unto Labs | San Francisco, CA | ONSITE (Hybrid OK), REMOTE (US) | Full-Time Unto Labs is developing the Thru Layer-1 blockchain (https://thru.org) We recently announced $14.4 million in funding to make blockchains & digital assets useful for the world. Founded by Jump Crypto alumni and core contributors to the Solana protocol and the Firedancer client (https://github.com/firedancer-io/firedancer), we’re tackling fundamental scalability, performance, and usability challenges in distributed ledgers.

Our runtime conforms to the RISC-V specification—moving away from domain-specific VMs, DSLs, and bespoke compiler toolchains that limit developer and institutional adoption. You can write smart contracts and programs in any LLVM compatible programming language and reason about a standard ISA in RISC-V. Components are developed in C for maximal control over performance and resource usage.

We believe there is a unique window of opportunity to developer fairer, more accessible, and more global financial products on resilient public blockchains.

You can check out our docs and open-source developer tooling at docs.thru.org and https://github.com/Unto-Labs/thru/

We are hiring for the following role(s):

- Systems Engineer: https://jobs.ashbyhq.com/unto-labs/13df6bea-b253-4c80-ae05-5...

SalesJack | Software Engineer (full-stack) | Hybrid (Hamilton/GTA Canada) | C$130K-C$150K + equity and benefits | salesjack.com

SalesJack is a sales software platform (CRM, Prospecting Service) for independent businesses in the construction supply industry. We are growing quickly and profitably. Our founding team and customers are based in the US, and we aim to grow engineering capabilities in Canada.

As a Full Stack Software Engineer at SalesJack, you'll lay the technical foundation for new features and products used by construction supply businesses. You'll work closely with founders and lead engineers, owning major parts of our greenfield product development. We highly value a startup mentality—taking initiative, moving quickly, and iterating solutions based on real customer feedback.

We are looking for:

- 2+ years experience as a full stack software engineer (professional or notable personal projects)

- Strong knowledge of React.js and Next.js for frontend development

- Experience with either Node.js or Java Spring Boot for backend APIs and services

Our hiring process will be:

1. Initial call with our founding engineer to briefly discuss your experience and introduce SalesJack ~ 30mins

2. Technical Exercise (this will a live coding on a screen-sharing call where we will ask you to work on some problem) ~1.5 hours

3. Call with one of our founders to see cultural fit ~ 30mins

4. Offer

Apply here and mention Hacker News: https://jobs.ashbyhq.com/salesjack/179cbe31-abb4-407c-a00a-b...

Kinelo | kinelo.com | Full-Stack Engineer (AI + Backend) | San Francisco | Onsite

Kinelo manages the new type of hybrid team that will emerge in the future: humans+AI working shoulder-to-“shoulder”.

Our first product helps human software engineering teams deliver more efficiently and more reliably by assisting in coordination and engineering management. But it’s built on a foundational layer that ingests data, knowledge, and process across communications and systems, exposing that to humans and AI alike.

Eventually, Kinelo will become a proper human+AI orchestration layer, managing entire companies, and our goal is to have Kinelo run Kinelo (we already dogfood it today).

We’re looking for high ownership individuals to join our small team and shape its direction. We also just opened a new SF office and new hires will have the ability to help shape company culture, engineering practices, architecture, and roadmap.

We’re well-funded (just raised another round), founded by a serial founder, anti-bureaucratic, and highly technical.

We’re looking for:

- Those who want to go 0 to 1 with high ownership: moving features and products from idea on a napkin, to prototype, to engineering UI, to shipped and polished product

- ~8 years professional experience, including the pre-LLM days with strong CS fundamentals

- A balance of wisdom from experience and optimism about the future

- Strong TypeScript and Postgres (or other RDBMS) experience at scale and with high reliability (SaaS apps, APIs, etc)

- Experience with a variety of technologies, including containerization, distributed systems, and at least one strongly typed programming language (Go, C++, Java, etc)

- Ideally experience with ML and AI systems (though expertise in ML, data science, etc is not needed for this role)

We can’t sponsor visas but relocation assistance to SF is possible.

Please apply here: https://job-boards.greenhouse.io/kinelo/jobs/4088659009 and also email jobs@kinelo.com, mentioning this post.