How deep tech startup Hartley Ultrafast accelerated their pre-seed target using ThatRound

Investors in this round: Sowing Capital & OVC Ventures

This case study, shared in partnership with ThatRound, highlights how Hartley Ultrafast secured its pre-seed funding in just six weeks by leveraging ThatRound’s network of vetted investors and syndicates.

Hartley Ultrafast: bringing light speed to computing

Hartley Ultrafast develops optoelectronic computing systems that collapse the gap between thought and reaction — effectively bringing intelligence to light speed.

By combining the communication power of photons with the computing precision of electronics, the company is creating a new generation of hardware built for ultra-low-latency AI inference and data processing.

Their technology pushes the boundaries of physics, enabling complex models to run within a single nanosecond and delivering huge energy efficiencies — all achievable with existing technology. With 100x faster inference and 1000x quicker optimisation, Hartley Ultrafast is transforming performance in sectors such as finance, telecommunications, data centres, industrial automation and healthcare — places where every microsecond counts.

Fresh out of stealth mode, the team launched a full rebrand at Microelectronics UK 2025, unveiling their new name and their demonstrator machine, Babbage. The event marked their shift from research project to commercial deep tech company ready for scale and investment.

Finding investor matches, faster

Like many deep tech founders, the Hartley Ultrafast team faced one key challenge — fundraising velocity. Identifying investors who truly understand advanced frontiers like photonics and microelectronics is often a slow, fragmented process.

Using ThatRound’s partner network, the company raised its £500k pre-seed in just six weeks, with investment from Sowing Capital and OVC Ventures, alongside their lead investor, Strange Ventures, a Silicon Valley-based early stage VC.

“The ThatRound platform helped us accelerate our raise — we closed £500k of our pre-seed in just under a couple of months. The ability to easily find, compare, and apply to different investor syndicates and angel groups saved us enormous time and energy.”
— Josh Silverstone, Founder & CEO, Hartley Ultrafast

By focusing on a curated network of qualified fundraising partners, the team was able to:

• Close their round faster

• Identify multiple strong partner fits

• Keep more focus on product and commercial development

Quality deal flow for investors

ThatRound’s infrastructure benefits investors too. By streamlining deal discovery, it surfaces investor-ready startups to the right networks faster.

Sowing Capital and OVC Ventures — angel syndicates and ThatRound partners with a focus on pre-seed and seed-stage startups — both invested in this pre-seed round. Each syndicate has a leader that manages their deal flow and uses ThatRound to source qualified opportunities to their angel members, reducing noise and improving alignment.

“Hartley represents exactly the kind of opportunity we look for: a high-conviction, asymmetric opportunity backed by exceptional IP and a world-class team. The speed and exclusivity of the round reinforced our belief that this is a business with real momentum.”
— Harrison Faull, Managing Director, OVC Ventures

The ThatRound process in action

So what did the journey from sign-up to investment look like?

1. Pitch Page created: Hartley Ultrafast built their ThatRound Pitch Page, outlining sector, round size, valuation, and equity offered.

2. Partner matching: After review, ThatRound provided a list of the most relevant funding partners based on mutual requirements.

3. Targeted applications: The team chose which partners to apply to, granting them access to the Pitch Page — allowing Hartley Ultrafast to stay in stealth mode while raising.

4. Direct engagement: Interested partners could then accept, message, and book calls directly with Founder Josh Silverstone.

“We were hugely impressed by both the scale of the opportunity and the calibre of the team. Accelerating compute efficiency isn’t just a trend — it’s a necessity in a world where AI and crypto are consuming unprecedented amounts of power.”
— Bradley Jones, Syndicate Lead at Sowing Capital

Lessons for early-stage deep tech founders

Fundraising in deep tech at the early pre-seed stages is notoriously slower. Many investors shy away from long paths to revenue or layers of technical risk. And deep tech ventures can take years to validate, making early-stage commitment harder to come by.

Hartley’s success proves that using ThatRound, a specialised, curated platform built to help founders secure funding, can seriously tilt the playing field. What normally takes months of outreach and diligence was condensed to weeks through ThatRound’s curated matching and transparent process.

For early-stage deep tech founders, the lessons are:

• Don’t benchmark timelines against B2B SaaS or consumer tech. The benchmark is around 3–6 months just to secure seed funding. 
• Investor fit matters more than volume. Deep tech raises need domain expertise and patience. Platforms like ThatRound bridge the gap between technical founders and capital-ready investors. 
• Close quickly once traction is visible. Momentum acts as a signal in deep tech rounds.
  

Infrastructure for match & discovery is a game changer. Without friction-reducing tools doing the leg work for them, many deep tech founders drown in admin, not innovation. Not forgetting that a transparent, data-driven approach builds trust on both sides of the table.Hartley Ultrafast’s story demonstrates that deep tech founders no longer need to choose between building and fundraising.

ThatRound is building the infrastructure to make that the norm, so the next generation of founders can spend less time chasing capital and more time focussed on building.

To find out how you can join ThatRound either as a startup looking for funding, or a partner ready to access quality dealflow, visit ThatRound