Tapitab is a stealth-mode fintech startup building a proprietary self-learning customer intelligence platform for the US hospitality industry. We are patent-pending across multiple core innovations and are moving fast toward launch.
We are looking for a Senior Software Developer to join our technical team and take full ownership of building our POS software layer — including payment integration, tab origination and settlement flows, and Android application development on a handheld payment device.
What We Need:
• 5+ years of Android development experience (Java or Kotlin) • Hands-on payment processor API integration — Stripe, Shift4, Fiserv, Worldpay, Finix, or equivalent • Deep knowledge of EMV, NFC, and contactless payment standards • Proven experience building POS software for bars, restaurants - hospitality industry • Prior work with leading POS system providers is a strong plus
Compensation: - Permanent: competitive salary + meaningful equity - Contract: competitive hourly/daily rate - Open to either arrangement depending on the candidate
This is not a general dev role. We need someone who has built payment flows before and understands the hospitality POS environment from the inside.
Referral bonus — refer someone we hire and we pay you $2,500 on their start date. No middleman.
Contact: info@tapitab.com
I’m sourcing candidates for a remote Software Developer role with micro1.
Relevant backgrounds: Python, Rust, Go, Java, Node.js, full-stack, Android, or iOS.
Details: Remote / Global Contract $60–$110/hr 100 openings 1+ years hands-on dev experience AI interview required
Apply: https://jobs.micro1.ai/post/774871bf-951f-4f26-9fe8-42eabfce...
Disclosure: I’m sourcing for this role as a recruiter partner, so the link includes referral tracking.
Jefit is a profitable fitness-tech company — 15+ years in market, no funding pressure, no enterprise red tape. We're hiring an experienced Android engineer to drive the Android side of our Adaptive Plan — a mesocycle-driven progressive-overload engine — end-to-end alongside our CTO. You'll see your code in front of millions of users every day.
What we care about (more than years on a resume):
You've shipped real Android products to Play Store — solo side projects count
Kotlin + Jetpack Compose + Coroutines, or you're actively learning them
AI-coding-assistant fluency is non-negotiable — Claude Code, Cursor, Copilot integrated into your daily workflow, not a name-drop
Offline-first / Room / SQLite mindset (we run in real gym environments where the WiFi is bad)
Extreme ownership end-to-end — feature, ship, polish, debug, repeat
We bias toward fast learners who already use AI to ship faster, over senior engineers stuck on a 2018 stack.
In-office in Santa Clara, CA. US work authorization required (no sponsorship).
Apply: https://tally.so/r/lbvOBN
Stpkr Technologies is hiring for the following roles to build the next generation of wearable devices.
We are currently looking for the following 4 roles but we are also open to interviewing any candidates who feel like they will do their best work here - even if your skillset/experience doesn't fit the current defined roles. Our current team doesn't fit the conventional mold, and we don't expect our future hires will either. If you don't fit the advertised roles, just send us a mail per the same process with whatever job title would fit you the best.
Work is in person near Noida Sector 18, walking distance from Sector 18 Metro Station. We prefer in office work, but we are super flexible overall, it will be hands down one of the best work environments you can get. Pay is competitive, and there are opportunities to earn meaningful equity down the line. We prefer current and recent undergraduates for our roles. If you are still in college we welcome you to apply nonetheless provided you can work as an intern for us in person. Super-flexible overall and all of our current team started out as interns.
Hiring across OS, full-stack, and hardware. AI policy across all roles: you should be able to do the work without AI, and much faster with it.
Android Systems Engineer (AOSP/BSP) - Everything at the OS layer. You've rooted phones, flashed custom ROMs, broken and fixed Linux for fun. Comfortable in C/C++. GitHub with kernel-adjacent or LineageOS-type projects a plus. Stack: Android, Linux, C, C++, Java. _Filter: send us something you built where you had to fight the OS or hardware.
Full-Stack Engineer (Apps + Backend + ML) - Everything at the platform layer. Generalist who ships end-to-end. Skill check: can build a crude-but-working facial recognition system (camera → model → DB → backend). (using existing facial recog models) Bonus for weird/constrained hardware work or running ML on edge devices. Stack: Android, Java, Python, TypeScript. _Filter: send the most useful thing you've built and used (no CRUD slop). Even better if you still use it for yourself.
Hardware Engineer - Bring-up/Debug/Integration - Take EVT/DVT boards and make them work. Comfortable with J-Link and IDE debugging, reading schematics and reference designs. KiCad/Altium/EasyEDA hobby work would make you ideal. PetaLinux experience or hunger to learn it. ECE undergrad fine. _Filter: photo of a board you designed or debugged, plus what went wrong.
Hardware Engineer - Power/RF/Wireless - Make the power and RF paths behave on EVT/DVT boards. Hands-on with schematic capture, layout, soldering, scope/logic analyzer. Given two unknowns, you pick one and start measuring. _Filter: sensor fusion work, how noise behaves across protocols, and SPI debug chops.
Founder's Office - Work closely with the founder and the rest of the team to manage the day to day and long term affairs of the company, the Man Friday of the company. Must have a decent degree of technical knowledge (we are a tech company after all) and be efficient at administrative tasks as well as management. Speed and learning ability are prized here, there will not always be a clear path to the work you have to do here, so you will have to figure some of it out on your own.
To apply, contact arnav@stpkr.in with the subject line "HN - Human" and a brief intro for further communication. Attach any documents you deem useful there. Please include the role you are applying for at the top of the email if it is one of the above mentioned, otherwise whatever role fits you best. Shortlisting will be online, interviews will be in person. We are hiring quickly, expect to hear back from us within 2-3 days of applying. If you don't, assume you will not. Thanks for your time!
Psiphon is a VPN app used by millions of people to access the open internet in regions where it's restricted. Small team, software that matters.
We're building the next-gen client app in Flutter (iOS, Android, macOS, Windows) and need someone who can work across both iOS native and Flutter. Split is roughly 65% Flutter, 35% iOS native (Swift, StoreKit, entitlements, network extensions). You'll have mentorship from a senior iOS specialist for the deeper networking work.
Day to day: Feature development in Flutter, iOS platform integration (subscriptions, permissions, App Store), and occasionally going deep into network extensions and packet tunnel providers. Small team (~3-4 core devs), high ownership, low ceremony.
Looking for: Strong Swift experience beyond just UIKit/SwiftUI app dev, comfort with the iOS ecosystem (App Store process, provisioning, StoreKit), and willingness to context-switch between Swift and Dart in the same day. Flutter experience is a strong plus but not required if you pick up frameworks quickly.
Contact: hr@psiphon.ca
Hi all, I’m Yuriy, founder of Puma.tech. Prev. worked at Cloudant (YC S08), Meteor (YC S11), Parse (YC S11, Facebook/Meta), and explored AI/ML (computer vision for self-driving cars).
We have 2 products:
1. https://PumaBrowser.com: iOS & Android mobile browser with built in LLMs & wallets – private local alternative to ChatGPT. 1m+ downloads.
2. https://PumaAI.com: small research lab focused on privacy and reliability of AI based on our experience building Puma Browser.
Open Roles: Eng (iOS/MacOS, Android, Ai/ML, Browser Extensions), Based Social Media Intern; Internships: Eng, Design, Growth
We’ve raised a few rounds from some of the best builders in ai and crypto:
Protocol Labs (YC S14), Chris Larsen (Ripple), Anatoly Yakovenko (Solana), Illia Polosukhin (NEAR Protocol), Sridhar Ramaswamy (Snowflake CEO), Jason Warner (poolside.ai, ex-GitHub CTO), Don Ho (Orange DAO, Quantstamp W18), Evil Rabbit (Vercel), John Phamous (SF Compute) and other amazing builders.
How to Apply: email careers+hn [at] puma.tech with your GitHub, a note on what you're most proud of building and what you'd like to build next.
Thank you!
- Radar 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, other mobile sensors and ML.
- 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 tim@radar.com
We build AI-assisted auditory training for people with hearing loss. Our product is live, in clinics, and growing internationally.
Backend Engineer: Postgres-heavy work on Supabase: PL/pgSQL functions, pgmq queues, Deno edge functions, billing and cron systems. You like databases enough to enjoy writing triggers and RLS policies, and you want to own systems end-to-end rather than just ship tickets.
QA Specialist: Manual testing of our iOS/Android app and web tools, working alongside our head of QA on a clinical product where data quality, platform stability, and accessibility are critical to our mission.
Note: Candidates must be in time zones no further west than EST; Western Europe is fine.
If interested, contact travis AT neurotone.com. Join us in making a difference!
MixRank processes petabytes of data every month through web crawling. Hundreds of customers use our data products, including Google, Amazon, Facebook, Intel, and Adobe, across industries such as finance, recruiting, sales, marketing, and security. We’re a fully remote company with a global footprint across 20+ countries. We’re growing, profitable, employee-owned, and have no dependence on outside funding. Applicants from all geographies and backgrounds are welcome.
We’re looking for passionate individuals for whom programming is not just a job, but something they genuinely love to do. We’re obsessed with computers, programming, big data, databases, compilers, hardware, math, data science, and the internet. Does this sound like you? Please apply to join our team.
Our codebase is friendly to new contributors. You’ll have a fully functional development environment within hours through full automation and will be pushing commits on your first day. Deployments to production happen multiple times per day and finish in under two minutes.Effectively all of our codebase is written in Python, Rust, SQL, JavaScript/TypeScript, and Nix. The core technologies you’ll need familiarity with to be productive are Python, PostgreSQL, Linux, and Git.
We operate at a larger scale than typical startups. We run two datacenters with high-performance servers we’ve built ourselves, capable of handling the volumes of data we process. We’ve implemented our own distributed file system, perform full-scale web crawls, and download and run static analysis on the entire universe of published Android APKs and iOS IPAs.
Unlike a typical startup where you might spend half your time in meetings and the other half fixing Jira tickets, at MixRank you’ll challenge yourself with difficult technical problems that help you grow as an individual. We’re continuously hiring for the positions below; these aren’t singular roles that close once filled. Our philosophy is that the candidate is more important than the position. For each new member of the team, we design a custom role and responsibilities around their interests.
Other companies may create a long list of specific requirements with the expectation that you’ll exactly replace someone on the team or fit a role defined by committee. MixRank is more pragmatic: we first get excited about bringing a unique individual onto the team, then figure out the best way to support their specific talents.
Junior Software Engineer - Remote (Global), Full-Time
We’re looking for remote junior engineers with 0–3 years of professional software experience and 5+ years of curiosity exploring computers, programming, and technical hobby projects.
This is an open-ended entry role with mentorship and diverse opportunities to work across all areas of our product: databases, distributed systems, infrastructure and tooling, data analysis, machine learning, frontend/backend web development, APIs, data mining, data modeling, and more.
To stand out, please highlight what makes you unique: passion for computing, curiosity and side projects, work ethic, niche research, or anything else that shows how you think and build.
Ideally, you’ve already graduated. But if you still have one or more years left of school, please feel free to apply anyway. If you’re the right fit for the team, we’ll figure out a way to accommodate your schedule.
Apply here: https://www.ycombinator.com/companies/mixrank/jobs/Fnwsojk-j
Software Engineer - Remote (Global), Full-Time
We’re hiring generalist software engineers to work on web applications, data mining, machine learning/data science, data transformation/ETL, data modeling, database scaling, infrastructure, DevOps, and more. We’ll tailor the role to the subset of areas that best match your interests.
Beneficial experience includes PostgreSQL, Python, Rust, Linux, TypeScript, Nix, frontend/backend web development, and data mining.
Apply here: https://www.ycombinator.com/companies/mixrank/jobs/RXQspen-s
I’m Kiran, Chief of Staff at MixRank, a fully remote data startup building go-to-market intelligence. We’re US-incorporated but hire globally, and we’re bringing on new teammates to join a fast-moving team with real ownership and impact.