Alembic | SF (5 days onsite) | SRE • C++ AI • Backend Python • Data Engineering

Causal AI at scale for Fortune 500. We melted GPUs building this—now running one of the world's fastest private supercomputers. The only non-Fortune 500 company in the world to operate such a system. Customers: Nvidia, Delta, Mars. $145M Series B.

Hiring now: SREs for supercomputer infrastructure, C++ engineers for AI systems, data engineers for enterprise-scale pipelines, backend Python engineers for our platform.

Story: https://venturebeat.com/ai/alembic-melted-gpus-chasing-causa...

Job Board: https://jobs.ashbyhq.com/alembic?utm_source=LrrO1q3Bmk

Fullstory | Remote (US), Atlanta, London, Bogotá, Czechia | https://www.fullstory.com/

Fullstory provides privacy-preserving session replay and analytics for websites and mobile apps. Our session replays are nothing short of magical - they look almost like a video of the user's screen (with private details redacted) - and the combination with analytics creates eye-opening insights.

Remote (US):

* Senior Software Engineer, Android - $160~170k - Java, Rust, Kotlin, Compose Multiplatform - https://www.fullstory.com/careers/jobs/3be8b5f8-b05c-4221-b9...

* Senior Software Engineer, iOS - $160~170k - Objective-C, Swift, SwiftUI - https://www.fullstory.com/careers/jobs/1c9234a4-af67-428d-91...

Atlanta, USA (1 day per week in office):

* Software Engineer, Digital Experience Analytics - Go, TypeScript, GCP - https://www.fullstory.com/careers/jobs/a786962d-68c1-48fa-8b...

* Software Engineer, Subtext - AI agents, Go, TypeScript - https://www.fullstory.com/careers/jobs/073bfc41-0ac6-4e59-a5...

We have additional engineering and product design roles open in Colombia and Czechia as well as other roles in product management, sales, HR, support, and solutions in the US and UK. See the full list at https://www.fullstory.com/careers?ashby_jid=bce3fcba-6b80-43...

For US roles, you can expect regular raises & bonuses, equity, and benefits including: health insurance, 401k matching (Vanguard), annual learning stipend, unlimited PTO, parental leave, and more. I take about 4-5 weeks vacation a year, in addition to ~3 weeks worth of company holidays (federal holidays + the week of Christmas to New Years.)

Folks in other countries can also expect a strong benefits package, but I'm not as versed on the details.

Additionally, you get a 5-week sabbatical after 5 years of employment - I took mine about a year ago, and it was fantastic.

To apply, please submit your info on the website, and our recruiting team will get in touch with you. If you have questions, feel free to reply here or contact me directly. (I'm an engineer on the iOS team, but I'll do my best to answer questions.)

Arenko (energy transition/batteries and renewables) | London, UK | 2x/week in office

We work on industrial/grid-scale batteries and other renewable generation: monitoring, managing and trading them on multiple energy markets. Batteries like these: https://en.wikipedia.org/wiki/Battery_energy_storage_system Everyone starting from the C-suite is passionate about addressing climate change and transitioning to renewable energy!

We're a small team of 7 backend engineers atm (other teams have Ops, FE and DS roles). We have paying customers and have been around for 10 years. Our current goal is to make the platform more scalable to deal with the customer growth and move to new markets. The biggest challenge is understanding how the various energy markets and energy storage in general work and then translating that to reliable working software.

We're currently looking for a Senior Backend Engineer (Go). Our office is in London Blackfriars and most engineers come in about 2 days a week, but this is flexible.

Feel free to message me with any questions or apply directly:

https://arenko.bamboohr.com/careers?source=hn

https://arenko.group/careers/

Modall | Frontend Developer (React/Next.js) | Uxbridge, ON (Greater Toronto) | On-Site | C$60-80k

We're a 5-person dev agency building AI, Web3, and SaaS products for startups, NFL players, and enterprises.

Stack: TypeScript, React, Next.js, Tailwind, React Native | Node.js, Prisma, PostgreSQL

The work: You'll ship pixel-perfect UIs from Figma designs, make architectural decisions, and see your code go into production for real clients. No legacy maintenance, just greenfield builds.

Strictly on-site (Mon-Fri, 9-5:30pm) because we believe in high-bandwidth collaboration. No remote.

Outside of client work, we also incubate internal SaaS products. Team members can contribute to these projects outside regular hours for equity if interested.

Apply: https://modall.breezy.hr/p/552471e37316-frontend-developer-r...

Kredit | .NET Engineer Roles | Remote (US) | Full-time

Kredit (https://www.kredit.fyi) is on a mission to resolve consumer debt. We help people get out of financial hardship and offer tools for companies looking to manage their internal processes. Kredit is a small team and growing.

Our stack: .NET Core, C#, PostgreSQL, CQRS, Angular, GCP, Kubernetes, Terraform and much more.

We are looking full-stack engineers that have a .NET background, eager to learn and motivated to work in a startup.

If this sounds interesting to you, please reach out to recruiting at trykredit.com

x2A | NYC, NY, USA | ONSITE | https://x2a.tech

We are actively looking for multiple software developers or software engineers to join our team (in the office, 5 days/week). These positions primarily focus on our 5off software product (puzzles/games).

There is zero expectation for you to be proficient in all aspects of the tech stack. We are looking for people who know some of these technologies and are excited to share their expertise while developing their skills and learning new things.

We welcome candidates at any experience level, with or without academic qualifications. For junior candidates, do not hesitate to share related personal projects.

Tech stack:

  - Languages: Python, Typescript, Swift, Rust, C++.
  - Backend: SQLAlchemy, PostgreSQL, Litestar.
  - Frontend: Svelte, Tailwind.
  - Mobile: Swift, SwiftUI.
  - Cloud: AWS, AWS CDK.
  - DevOps: Gitlab.

More https://x2a.tech/careers/openings/ for more details and how to apply.

Microsoft AI | Platform Engineering | Full-time | Seattle, WA or San Francisco Bay Area | ONSITE (4 days/week)

We're building the platform primitives that power https://copilot.com (Microsoft's ChatGPT). If you've shipped systems at scale—whether backend services, distributed infrastructure, ML platforms, or consumer AI products—we want to talk to you.

The work: design and build secure, performant platform services for AI at scale; collaborate with infrastructure, product, design, and research teams; ship high-quality code that reaches hundreds of millions of users; move fast in a design-driven environment.

You: solid fundamentals in systems thinking and software engineering; fluent in Python, C#, C++, Java, JavaScript, or similar; shipped real products or systems people use; can communicate across technical and non-technical teams.

Compensation: Competitive with other frontier AI companies, commensurate with experience

We're actively hiring and will respond to applicants. Check https://microsoft.ai/careers for current openings, or email maiplatformjobs@microsoft.com if something specific doesn't fit the bill. Apply directly if genuinely interested in building the future of AI.

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.