Duolingo | Full-time | Multiple roles | $177K-$240K for NY roles | NY and London | Hybrid

Our mission is to develop the best education in the world and make it universally accessible. Our culture is eng-driven, friendly, and very data-driven thanks to our large userbase. Check out our blog to see what engineering at Duolingo can look like: https://blog.duolingo.com/hub/engineering/

Tech stack: (frontends) Swift/Kotlin/TypeScript, (backend) Python/Kotlin/Postgres/Dynamo, (infra) AWS/k8s/Terraform.

We're always hiring for engineers. A few roles below:

Senior Engineering Manager, Chess (NY) https://careers.duolingo.com/jobs/8385137002

Senior Android Engineer (NY) https://careers.duolingo.com/jobs/8217266002

Senior iOS Software Engineer (NY) https://careers.duolingo.com/jobs/8318257002

Engineering Director (London) https://careers.duolingo.com/jobs/8444624002

Senior Gameplay Programmer (London) https://careers.duolingo.com/jobs/8424809002

Base salary: $177-240K for the NY-based roles, unsure about the London-based roles.

Perks: free lunch, 2-week winter break + 20 days of flexible time off.

Trayd | Engineers + Product / Ops Roles | NYC (ONSITE) https://buildtrayd.com

https://jobs.ashbyhq.com/trayd

Trayd is building the financial operating system for commercial construction. Contractors still run payroll, compliance, and job costing across spreadsheets and legacy software. We replace that stack with a single platform that automates payroll, union compliance, time tracking, and job costing.

Construction payroll alone moves ~$260B annually in the U.S., and most of the industry still runs on outdated tooling. We’re rebuilding that infrastructure from the ground up.

Small, senior team with high ownership. Engineers own systems end to end and work directly with leadership and customers.

Stack: TypeScript, React, Next.js, React Native, Node.js, Postgres

Location: NYC (SoHo office), fully in person.

Open roles Engineering – Senior Software Engineer Product – Product Operations Associate Implementations – Implementations Analyst, Senior Implementations Analyst Customer Success – Customer Success Manager

All roles: https://jobs.ashbyhq.com/trayd

Blackshark AI | Software Engineers & Platform Engineers | Full-time | Austria or Remote EU Hours | VISA sponsorship available

We build geospatial AI infrastructure. Our platform lets analysts train custom object and change detection models on satellite/aerial/drone imagery in minutes, then reconstructs 3D terrain from those detections. We just shipped a planetary-scale simulation platform with Lockheed Martin powered by Unreal Engine.

If you want to work on distributed systems that run in a data center one day and an edge laptop the next, we have interesting problems. Our training and inference infrastructure is processing trillions of pixels and we deliver real world impact for our customers across defense, intelligence, and local governments.

Tech Stack: Python, Fast API, PyTorch, Postgres, Redis, Vue.js

Infrastructure Stack: Kubernetes & Docker, Linux, AWS & Azure, Azure DevOps, Terraform, ELK, Prometheus & Grafana, ArgoCD & Helm

Roles:

Software Engineer - Frontend UI https://jobs.eu.lever.co/blackshark/5c596b85-5134-4601-be25-...

Software Engineer - Data Plane Team: https://jobs.eu.lever.co/blackshark/6110fedd-5cd8-40e5-ac11-...

Software Engineer - Machine Learning Team: https://jobs.eu.lever.co/blackshark/7c4b0833-790b-4490-b24a-...

Platform Engineer - Deployment Team: https://jobs.eu.lever.co/blackshark/56a85834-d986-4105-9cc8-...

or reach out to HM with questions at: 'eivanov@' + username[:-2] + '.' + username[-2:].lower()

Howie | AI for Architecture & Engineering | Hiring Backend | Vienna / Remote (Europe) • Senior Backend Engineer (Architecture & AI Systems) | Vienna / Remote (Europe) | Full-time | Salary + equity

Early-stage startup building an AI platform that helps architecture and engineering teams reuse knowledge from past projects (documents, drawings, revisions) to reduce costly rework in planning and pre-construction.

You’ll work on multi-tenant backend systems powering hybrid search, document ingestion pipelines, and large-scale indexing across complex engineering datasets.

Stack / areas: PostgreSQL, Elasticsearch/OpenSearch, vector search, distributed systems, async pipelines.

Looking for: 8+ years backend engineering experience, strong systems design skills, experience with distributed systems and production B2B SaaS.

Small team (currently <10 engineers), high ownership, real production users.

Backed by Pi Labs and DAR.

Full JD: https://howie.systems/careers Contact: contact@howie.systems

Colonist | Full-Stack Product Dev | Remote (Eastern Europe / SEA) | Full-time

Colonist.io (https://colonist.io/) is a multiplayer web strategy game with millions of players, think Catan, but free and online. We're a small team and you'd own features end-to-end, from backend game logic to polished UI.

You'd work on evolving our game architecture, ensuring cleaner code boundaries and better scalability.

Stack: TypeScript, Node.js, React, CSS, PostgreSQL/SQL. We lean heavily on AI tooling for development speed.

More details and apply: https://jobs.ashbyhq.com/colonist/109d62c4-52f3-4980-9c49-d3...

Comulate | Senior Engineer (3+ YoE) | ONSITE in San Francisco, CA

We're building automation software for the $7T insurance industry, accelerated by AI. Seed stage in terms of headcount (~ 20 people) but Series B in terms of business traction (+ cash-flow positive). We've intentionally stayed under the radar.

- Product has caused customers to literally cry tears of joy

- Experienced eng team from Airbnb / Brex / LiveRamp

- Stack: TS, Postgres, React, GraphQL, and Next.js

Apply here: https://about.comulate.com/careers

Di Rezze Family Office | AI-Native Technical Operations Lead | Miami, FL (ONSITE) | $130K-$200K + Early Equity | Full-Time

We're building an AI-native clinical data platform from the ground up, not a legacy system with AI bolted on. AI is core to the architecture, the development workflow, and the product itself. Fully funded by a private family office, no outside capital needed, no fundraising runway concerns. We're assembling the founding team now.

We're building a founding team to revolutionize healthcare in the United States, and we're hiring a technical operations lead. Best analogy: studio engineer to a recording artist. You own the environment so engineering leadership stays on high-leverage product work. That means CI/CD, QA, testing infrastructure, compliance documentation, and 30-40% independent feature development. Ground-floor equity in a company that's pre-revenue by choice, not by circumstance.

Hard requirement: you are already shipping software with AI coding tools daily (Claude Code, Cursor, Copilot, or similar). Not curious about AI. Not experimenting. Actively building and deploying with it. If you can't show us something you built with AI tools in the last 60 days, this isn't the right fit. Stack: React/Next.js, Python, PostgreSQL, Docker, AWS. But we care more about polyglot instincts than any single framework.

What we're looking for:

3-7 years full-stack experience Strong QA discipline (you write tests because you want to, not because someone made you) DevOps comfort: Docker, CI/CD pipelines, cloud infrastructure Self-directed. We don't micromanage and don't plan to start. Must be US-based or already have US work authorization. We do not sponsor visas.

What you get:

Meaningful early-stage equity (not a token option grant)

Direct access to founders and decision-makers, no layers

A say in the technical architecture from day one

Relocation to Miami fully covered

Health, dental, vision

Interview process: 15-min screen (show us your AI-built work) > take-home exercise > 2-hour paid working session > culture fit conversation.

Email: jpd@direzzefamilyoffice.com, subject line "HN March 2026" so I can find you.

Tangible Materials | AI Engineer | Remote (US/Canada) | Full-time | $140k - $160k USD + equity at seed startup.

Tangible Materials helps the construction industry to make better decisions around building materials. This means using less and better materials. We use AI to parse very complex construction documents to estimate quantities, track design decisions and detect over-design.

In this role, you'll help build the next version of our core technology by creating an agentic takeoff system.

Stack: Ruby, Rails, Typescript, React, Postgres, Redis.

https://careers.tangiblematerials.com/jobs/cad58c98-2666-466...

No visa sponsorship at this time

Littlebird.ai | Sr. AI SWE's + React/RN + Product Analyst | Global+remote | Full-time

Littlebird is your AI-powered personal operating system. We capture context from your daily life -- meetings, messages, browsing, notes -- and use it to help you remember everything, prioritize your day, and solve real problems. If you get excited about designing bleeding edge personal agents, persistent memory, or conversational inference...please see below!

Our team: includes multiple ex-founders + YC alums based in the US, EU and IST

Core stack: Python, Swift, React / RN, Postgres

Sr. / Staff AI Systems Engineer: https://jobs.gem.com/littlebird/am9icG9zdDrOmVuqR5Sy4TSPZbhE...

Applied AI Engineer: https://jobs.gem.com/littlebird/am9icG9zdDpftgr_F1AcbaNAqQWn...

Sr. React / RN Engineer: https://jobs.gem.com/littlebird/am9icG9zdDrfqJE9Qs--i1a3EQck...

Product Data Analyst: https://jobs.gem.com/littlebird/am9icG9zdDqi-y222tVeoibOKM3-...

To apply, click on the links above and send us a resume and any github or personal projects you are proud of.

Reckon Digital | Full-Stack Software Engineer | UK or remote | Python, React, AWS

We are looking for an experienced Full-Stack Software Engineer to work with us on an upcoming project for a large humanitarian organisation. Required: Python, React, AWS, Postgres. The place of work is London, UK but we're open to remote applicants as well (UK or international).

More info on what we do at Reckon Digital: https://reckondigital.com/

Interested? Email us at jobs@reckondigital.com! Make sure you include an updated copy of your CV.

Epoch Blue | Senior Full Stack Engineer, Senior Solutions Engineer | Hybrid (London, King's Cross) | Full-time | Visa sponsorship

We’re building the first-mile supply chain intelligence for agriculture and forestry. Our API and platform monitor 10M+ farms across 120M+ hectares - automating deforestation, carbon emissions, biodiversity metrics and water impact for enterprise agri-commodity brands, compliance platforms and NGOs. We’re API-first, geospatial driven and used by customers like Sphera, Assent, WWF and Golden-agri resources. We’re Google Cloud Partners too.

Small, high-output engineering team. Real ownership, direct work with founders.

Senior Full Stack Engineer - TypeScript across the full stack. TanStack Start / React 19 / Vite frontend with geospatial map views (Mapbox GL, MapLibre, Deck.gl). PostgreSQL with Drizzle ORM. You'll own database schema design, server-side APIs, auth architecture (Better Auth, enterprise SSO, B2B multi-tenancy), and ship features end-to-end.

Senior Solutions Engineer - Technical backbone of our customer engineering function. Own enterprise integrations end-to-end, run geospatial and statistical analyses on supply chain datasets (Python, GeoPandas, XArray, Dark), debug complex multi-system issues, build reference implementations, and be a credible technical voice in pre-sales. Strong Python, SQL, REST API, and geospatial data experience.

Both roles: competitive salary + equity, hybrid with our London office in King's Cross, visa sponsorship available (no relocation costs).

https://epoch.blue william@epoch.blue

Instinct Science | Senior Full-Stack Engineer | REMOTE (US) | Full-Time | $150K–$175K

Instinct Science is the AI leader in veterinary medicine - and we're just getting started. Our platform is already transforming how veterinary teams practice, combining a cloud-native EMR with real-time clinical decision support and applied AI that saves animal lives every single day. We didn't enter this space to make incremental improvements. We're here to disrupt a massive, underserved industry from the ground up - and we're looking for the engineers who want to help us define what comes next.

What you'll work on:

Own projects from scoping through release Build full-stack features using Elixir (backend) and React/TypeScript (frontend) Design scalable, reliable solutions in a small, cross-functional team

Stack: Elixir, React, TypeScript, AWS, PostgreSQL You're a strong fit if you:

Have solid experience building modern SaaS applications across the stack Thrive in a remote-first, async-friendly environment Care deeply about code quality and the end user (in our case — vets and their patients)

Nice to have: Deep Elixir/Erlang experience, AWS, relational DB design Compensation & Benefits:

$150,000–$175,000 base Medical, dental, vision + 401K with match Generous stipend for wellness, professional development, and your pet(s) "Flow State Fridays" and owner-like flexibility over time-off Annual all-expense-paid company retreat

Apply: https://instinctscience.applytojob.com/apply/1H156iuuzg/Seni...

Hiring – REMOTE LATAM - We build AI tools that help high-volume law firms manage their caseloads more efficiently. Our first product—an AI assistant that transcribes and classifies inbound calls—is in production. We’re now expanding into case tracking, follow-ups, and full workflow automation.

Looking for:

AI Engineer: 4-6 years of experience in AI/ML engineering.

Tech Lead: Lead a senior team, shape product and tech, work closely with founders.

SRE: DevOps & Infrastructure Engineer // CI/CD and Kubernetes

Tech Stack: Python, TypeScript, Postgres, Kubernetes, GCP Languages: Spanish + English.

Apply here: https://tramcase.na.teamtailor.com/jobs

CVector | Senior Software Engineer – Backend & AI Infra | New York City (FiDi) | ONSITE | Full-time | VISA SPONSORSHIP

CVector builds software to bring real-time economic optimization and AI prediction to every energy and manufacturing plant. We fuse live asset data with market dynamics into one decision layer that continuously forecasts, simulates, and optimizes — so plants run closer to their true economic potential every day. CVector recently raised $5M seed, read more on TechCrunch: https://techcrunch.com/2026/01/26/ai-startup-cvector-raises-...

We're looking for a senior backend engineer to evolve our core platform — time-series data systems, AI-assisted analytics, cloud infrastructure, and data ingestion pipelines. You'll take ownership of complex systems, drive major technical migrations, and shape how intelligence is embedded into industrial energy workflows. Think: AI evals and prompt engineering, MQTT ingestion pipelines, time-series schema design, PostgreSQL infrastructure, and ML platform support.

Stack: Python, TypeScript, Supabase, PostgreSQL, MQTT, TigerData, InfluxDB, AWS. 5+ years experience building production backend systems. FinTech, quantitative analysis, or econometrics background is a strong plus.

$125K–$150K + meaningful equity. Reach out to me at jnapoli+hn@cvector.com

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

We’re building the biggest 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 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

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/

Neocom | Senior Python Engineer | Onsite | Munich, Germany | Full-time

Neocom is a digital shop agent for online shops. Customers can chat naturally, get clear guidance, and find the right product faster, just like talking to a great salesperson in a physical store.

We've been in the guided selling space for the past 6 years and launched our new product, the Shop Agent, last year in November. Our customers who are already on this new product are loving it and demand more and more features.

We are now looking for founding engineers who can help our engineering team (5 people). We consider our selfs as craftsman, who care a lot about quality. A lot. We have a Python backend stack (fastapi, django, pydanticai), lots of postgres and typescript react frontends.

Ping me (CTO) at ssl @ neocom.ai

Newbuilds | Remote Senior Ruby on Rails Developer | Remote (Europe) | Full-time

Newbuilds is hiring a Senior Ruby on Rails Developer to help scale a widely used proptech marketing platform, a Norway-based proptech company powering automated campaigns and data-driven workflows across 17+ countries.

You’ll work on backend architecture, improve performance and scalability, build integrations with external APIs/CRMs, and influence technical direction with ownership over your code. This role is remote-first with flexible work and competitive senior-level compensation.

Remote (EU timezone friendly) | We work via B2B, or employment in Norway or Germany

Modern stack: PostgreSQL, Sidekiq, RabbitMQ, AWS, Docker, GraphQL

Join a low-ego engineering team with real product impact

Apply or share with someone who’d love working on complex backend challenges: https://careers.staffer.ai/jobs/7247377-remote-senior-ruby-o...

LiveEO | Senior ML Engineer | Berlin, Germany | Hybrid | Full-time

LiveEO leverages high-resolution satellite imagery and AI to provide actionable insights across industries—like protecting power grids, monitoring critical infrastructure, and ensuring deforestation compliance.

We are looking for a Senior ML Engineer to build and scale multitemporal, multimodal computer vision models for Earth observation. You’ll combine optical and Synthetic Aperture Radar (SAR) data into robust representations. This role is a true balance of applied research and engineering: you’ll own the full ML R&D lifecycle from data standardization and SOTA model development to rigorous evaluation and production-grade delivery.

Tech Stack: Python, PyTorch/Lightning, Databricks, MLflow, Ray, Prefect, AWS, Geospatial stack (GDAL, Rasterio, GeoPandas, STAC), PostgreSQL.

What we're looking for:

* Strong Python engineering and deep PyTorch/Lightning experience.

* Proven experience implementing and training deep learning models at scale.

* Hands-on experience with satellite imagery (optical & SAR strongly preferred).

* Strong CV fundamentals (representation learning, supervision, evaluation) and ML experimentation (Databricks/MLflow).

* Pragmatic mindset: you can take SOTA papers to validated baselines and production under real-world constraints.

Must be living in or willing to relocate to Berlin. This role requires German/European citizenship due to legal/regulatory requirements.

(Bonus points for experience with large-scale geospatial foundation models, VLMs, or distributed compute with Ray).

Apply here: https://liveeo-gmbh.jobs.personio.de/job/2540514

Journee | Berlin, Germany, Europe | REMOTE (CET +/- 2h) | Full-time | https://journee.ai & https://ojin.ai/

==========

Journee is a technology startup founded in 2020. Our in-house low-latency streaming technology and GPU fleet orchestration systems are the engines behind our award-winning work with brands such as BMW, H&M, and Siemens.

We are now building and launching Ojin (https://ojin.ai/), a real-time generative AI platform for developers. Ojin provides the APIs and inference infrastructure for developers to build and scale interactive applications and AI agents. For this new venture, we are building a small, ambitious team of highly talented individuals and are hiring for the following position:

* Senior Product Engineer

* VP of Technology

Our tech stack: TypeScript, React, Python, PostgreSQL, WebRTC, AWS, Infrastructure as Code, Unreal Engine

Apply here: https://job-boards.eu.greenhouse.io/journee

krea.ai | Senior Backend Engineer | San Francisco, CA | ONSITE | https://www.krea.ai

krea does AI research & builds AI tools for image generation, video generation, node-based workflows, LoRA training, and more. Small, mostly in-person team with a view of Alcatraz from the office window. Our users range from hobbyists all the way to professional designers at Apple or architects at firms behind The World Trade Center or Burj Khalifa.

We're looking for senior backend engineers. You'd work across our SvelteKit app (Postgres, Redis, Docker, ClickHouse), Python ML inference on GPU clusters, and k8s clusters across multiple cloud and GPU providers.

Some recent projects:

- building canary deploys with cookie-sticky traffic splitting - implementing durable execution for long-running workflows - designing our public API with OpenAPI docs auto-generated from Zod schemas - implementing enterprise-grade authentication, authorization, and permissions - optimizing ML inference for our hosted image generation models

We care way more about first-principles and core engineering skills rather than specific shenanigans around programming languages or particular tooling—knowing a lot about old UNIX principles is a plus though.

You should be comfortable owning things end-to-end. Experience with GPU infra is a plus. Many of us have some kind of creative background, it helps when building tools for creatives but is not a requirement by any means.

To apply, email d+hn@krea.ai (use the +hn suffix to make sure your email is prioritized!)