Deputy CTO

Joi AI is a platform for AI-lationships — personalized, emotionally intelligent connections between people and AI characters. We build characters that have their own personality, mood, and voice: they can ignore you, argue with you, miss you. If you've seen the film Her — that's roughly where we're headed.

Our platform serves both emotional and intimate needs without judgment, built on the values of rejection-free connection, sex positivity, freedom to be yourself, and ethical integrity. Today we have tens of millions of conversations on the platform. Our goal: 10% of the global population in long-term AI-lationships with our characters.

Joi Lab (joilab.ai) is our open research arm — we build open-source generative models, agent architectures, and training infrastructure. All code, weights, and data are public. We're not chasing the next ChatGPT wrapper; we're working on true AI agency: persistent memory, self-modification, self-authored constraints.

The role

You'll be the person the CTO can hand almost anything to — a gnarly architecture call, a team that's stuck, a feature that has to ship — and trust it gets done right. When the CTO isn't in the room, you're the one who represents technical leadership without missing a beat.

This isn't a title that sits above the work. It's a role for someone who leads from inside it: still writing code, still shaping architecture, still close enough to the details to know when "we can't do this" is real and when it's just hard.

You'll take a small team (5–10 engineers) and a business problem, and own the whole path between them — the architecture, the decisions, the delivery, and yes, the unglamorous infrastructure and operational work that most people would rather someone else handled. The team is small and flat, so your leverage isn't authority. It's the fact that you build, you decide clearly, and you lead by example.

This is a moment where a strong technical second-in-command can genuinely shape both what gets built and how fast it ships.

WHAT YOU’LL DO

• Act as the CTO's second-in-command across backend and ML teams, representing technical leadership in the CTO's absence

• Own architecture and technical decision-making for products and features, end-to-end

• Stay hands-on — dive into the code, ship features yourself, and prototype functionality when it's the fastest way forward

• Translate business problems into technical solutions: take a small team (5–10 people) and a business need, and drive it to a working result

• Lead people: hiring, offboarding, compensation and resourcing decisions, and team syncs

• Own cross-team alignment and synchronization with peers at CTO / CDO level

• Manage infrastructure, architecture, and the operational side without treating any of it as beneath you

• Drive execution in an environment where priorities shift constantly

WHAT WE’RE LOOKING FOR

• Strong backend engineering background — you think in architecture and can build systems in your head (C# / Python preferred; strong Java or other backend experience also welcome)

• Genuinely hands-on: still writing code and able to deliver a feature yourself

• Solid business understanding and the ability to connect technical and business goals

• Real people-management experience: hiring, team leadership, resourcing

• Comfortable across the full spread — architecture, delivery, infrastructure, and operational work

• A startup mindset: you operate in a small, flat team and lead by example

• Curiosity that hasn't faded — even after years in the industry, you still want to try new things

• Clear, structured thinking and communication: you answer the question you're actually asked, and when you're uncertain, you can say exactly what you're uncertain about

• Senior-level experience (8+ years), including:

  • hands-on development experience

  • a technical leadership / management role

WHY JOI

• You're joining the company that's redefining what relationships with AI look like — before the category gets crowded

• We move fast: ideas become live experiments in days, not quarters

• Joi Lab gives you access to frontier model research — open-source, no corporate gatekeeping

• Small team, high trust, high ownership — you'll see the direct impact of your work

• Work from anywhere with our fully remote, full-time setup.

• Standard 28-day annual leave policy.

• 7 yearly wellness days for life admin or recovery—no sick notes needed.

• Referral rewards up to $5000 for helping us hire top talent.

• We cover 50% of costs for training, conferences, and global meetups.

• Subsidized English classes through our corporate discount.

• Health support: receive up to $1,000 annually for medical fees or private insurance if you aren't on the group plan.

• Optimized workspace: we equip you in-office or provide $1000 every three years to perfect your home office or co-working setup.

• Peer-to-peer recognition: earn gratitude bonuses and swap them for swag, massage vouchers, or team adventures.

NEXT STEPS

• Intro call — conversation with the Recruiter

• Technical & experience interview — background, delivery cases, and system design task with CTO

• Final interview — culture fit and strategic alignment