Gurhan Kiziloz
Photo courtesy of Gurhan Kiziloz

There are operators who seek headlines, and those who accumulate scale quietly. Gurhan Kiziloz and Guillaume Pousaz fall into the latter category. Both lead companies that generate hundreds of millions, or in Pousaz's case, billions, in revenue, but neither is closely associated with product launches, press interviews, or public-stage visibility. Instead, they build through systems: revenue engines tuned around private control, low-profile execution, and tightly held operational structures.

Gurhan Kiziloz is the founder of Nexus International, which posted $546 million (£405.3 million) in revenue in the first half of 2025, up 110% year-on-year. Nexus operates across three distinct consumer platforms: Megaposta, a licensed sportsbook in Brazil; Spartans.com, a mobile-first casino; and Lanistar, a financial product with embedded gamified mechanics. All three are managed without external investors or board governance. Kiziloz retains 100% equity, zero dilution, and direct control over all strategic and operational decisions.

Guillaume Pousaz, founder and CEO of Checkout.com, leads one of Europe's largest payment processors. While Checkout.com has raised several billion in institutional funding, most notably a $1B Series D in 2022 at a $40B valuation, Pousaz has maintained a tight hold on governance. He retains majority control and has resisted calls for a public listing or major liquidity event. The company operates with a focus on long-term infrastructure and large-scale enterprise clients. Though its valuation has fluctuated in private markets, Checkout.com continues to process tens of billions in payment volume across more than 150 countries, with hundreds of clients in the enterprise and fintech space.

Both founders made decisions early to isolate their operations from traditional exposure points. Kiziloz avoided capital markets altogether. Pousaz, while participating in them, designed a structure that limited board influence and preserved operating latitude. Their communications strategies are minimal. Neither founder uses media platforms as primary leverage points. Product announcements are issued, not campaigned. Talent recruitment is targeted, not publicised. This restraint is not incidental; it is operational.

Their company architectures reflect their control preferences. Nexus is a multi-brand group, with each product functioning as a standalone entity under a shared ownership umbrella. Checkout.com is monolithic by comparison, with payments infrastructure consolidated under a single global platform. Kiziloz segments markets through brand identity; Pousaz centralises through technical depth.

Execution speed is a differentiator. Kiziloz's compressed hierarchy allows for decisions to be made and deployed within hours, particularly when it comes to entering new markets or launching product iterations. Pousaz, operating within a structurally larger organisation, moves more deliberately, optimised for compliance, integrations, and long-cycle enterprise partnerships. Both approaches yield outcomes; the trade-offs are between coverage and precision.

Financially, the contrast is just as clear. Nexus operates profitably, reinvesting internally with no external reporting obligations. Checkout.com, with significant institutional capital, balances aggressive technical investment with commercial discipline expected by its stakeholders. Each system works because its founder designed it to match their execution environment.

Neither Kiziloz nor Pousaz is especially visible outside of industry circles. Yet each oversees an organisation with scale, cross-border reach, and product relevance. They are not outliers in results, but in posture. While many of their peers operate with external validation loops, these two founders have optimised for independence, predictability, and internal leverage. Whether measured in H1 revenue or global transaction volume, their companies show that visibility and velocity are not always correlated. Some of the most structurally interesting organisations are being built in silence.