PrepCall
An AI voice coach for interview practice.
Product & Design Leader
Gideon Bullock
Most of what I’ve done well in twenty-five years, I’ve done by building a team and giving it room. This year I built two AI products of my own.
Seven years building design at Toyota. Eight at Songkick, from employee seven through Series C.
- Built design at Toyota from two people to 40+ at peak
- £10m internal revenue in its peak year, with full P&L
- Employee #7 at Songkick, from seed stage through Series C
- Shipped an AI voice product this year, now building multimodal emotion middleware
The work
Three cases
At Toyota I built a design organisation from two people to over 40, and the team took the app it was handed from 1.9 stars to 4.6. Before that I designed Songkick and Dopay myself. This year I built two AI products on my own. PrepCall is live, and Emotrix is in a pilot under NDA.
AI
Designing AI behaviour
When a product runs on a model, behaviour is the larger half of the design problem. What the system attempts. What it declines. How it responds to a signal it can't read. What it does once it has been running long enough to have a history. That behaviour is a surface in its own right and it needs designing with the same rigour as anything visible.
I designed how an empathic voice should respond in an interview practice session, then again for a clinical companion where the bounds are tighter. When PrepCall's quality started degrading by the fourth session, the cause was a system prompt that had grown six-fold on accumulated history. Hard character budgets now hold it inside a fixed envelope. Emotrix works a layer below that, on what a system is entitled to conclude from a signal before anything acts on it.
Projects
Things I've built
Verbalised Sampling Skill
A Claude skill that implements the Verbalised Sampling technique, recovering diverse outputs suppressed by alignment training.
Emotrix
Middleware for multimodal emotion intelligence.
Early stage, in a live pilot under NDA
nudge
A Claude Code plugin for the last stretch of building with an agent, the small visual corrections that are painful to describe in words.
Background
Now, and before
Currently
Building and advising at the AI layer, hands-on. Open to the right design leadership role.
- A live AI voice coaching product, designed and shipped end to end
- Emotion intelligence middleware, in a live pilot under NDA
- A venture business building several AI products on one shared set of components. Co-authored its operating model and playbook, covering how an idea gets picked up, how it is tested cheaply, when it earns investment, and how components get built once and reused. I also built and deployed the empathic AI voice demonstrator for one of its ventures, in health. The premise is that AI-assisted development makes building cheap, so the risk moves upstream to building the wrong thing, and the governance has to move with it.
Previously
Seven years at Toyota Connected Europe, building a design organisation from scratch to over 40 people at its peak, across connected vehicle apps, in-vehicle systems and digital services, with full P&L accountability. Employee #7 at Songkick, from seed through Series C. Part of the small design team at Skype during its growth from 11 million to over 200 million users. Six years at the BBC, leading design on the homepage, global navigation, and the project that became iPlayer. Chief Design Officer at a fintech in Egypt, launching mobile payroll for unbanked workers.
Earlier work
Songkick and Dopay are case two, where I designed the product myself. Before them came six years at the BBC (1998 to 2004) on the homepage, global navigation and the project that became iPlayer, and three at Skype (2004 to 2007) on onboarding and the referral loop.
Places I've worked
Approach
How I work
I've spent most of my career in places where design had to prove it was worth having. Early-stage startups with no design function, large organisations where design was seen as a downstream service, environments where the work was figuring out how to make design matter before you could do the design itself.
I ran the Toyota function on a full P&L, and I have sat in investment discussions, governance boards and strategic planning as the person accountable for design's numbers as well as its quality. Design leaders who can't talk about resourcing, utilisation and margin in concrete terms don't get taken seriously at the level where decisions are made.
The part of the job I care most about is developing people. Setting a clear bar, then giving people the context and autonomy to meet it. Several of the team I built at Toyota have told me it was the best team they'd ever worked in. That matters more to me than most metrics.
Craft & Delivery
- Product and service design across app, web, and embedded
- UX research strategy and standards
- Continuous discovery and validation
- Design systems direction
- Accessibility and inclusive design
Organisation & Operations
- Building design teams from scratch
- Operating models and team structure
- Resourcing, utilisation, and financial performance
- Global, distributed teams
Leadership & Influence
- Change leadership and digital transformation
- Embedding design into engineering-led organisations
- Developing design leaders
- Coaching, mentoring, and career development
- Senior stakeholder and executive communication
- Cross-functional alignment
- AI integration into design workflows
About
I studied graphic design in the early nineties, when there was one computer with internet access between forty of us and nobody had a mobile phone. The web arrived while I was learning about typography, print, and communication from Paul Rand and Dieter Rams. I've been working in interactive media ever since, through every wave from CD-ROMs and rave flyers to connected vehicles and AI agents. London has been home throughout.
I'm at a point in my career where the work I find most rewarding is helping other designers grow. Taking chances on people, giving them the room to figure things out, and helping them avoid some of the mistakes I made along the way. Several people I've hired and developed have gone on to lead their own teams, start companies, and do work that's better than anything I could have done alone. That's the part that lasts.
Writing
Thinking out loud
Things I've learned across three decades in design, about teams, organisations, craft, and the wider forces that shape how we live and work.
Contact
I’m open to a VP, Head of Design, or Design Director role at a company where AI is reshaping what it builds and how. I also take on interim design leadership, and I’ve been working on AI that reads emotional signals since 2023, first at Toyota and now in my own products.
Email gideonb@me.com, connect on LinkedIn, or download my CV.