Build38 is a mobile cybersecurity startup based in Barcelona, specialized in protection solutions for mobile applications. Its technology helps secure apps in sectors such as banking, healthcare, fintech, digital identity and mobility, protecting millions of devices worldwide.
| Startup | Build38 |
| Sector | Cybersecurity · Mobile application protection |
| Founded | Spain |
| Stage | Series B · acquisition |
| TSCFO services | External CFO · Financial due diligence |
| Main challenge | Supporting the finance function during a strategic corporate transaction |
| Solution | Consolidated reporting · KPIs · cashflow · data room · Q&A · negotiation |
| Key result | Acquisition announced in 2026 |
— 01 · STARTING POINT
A relationship that went far beyond the external CFO role
The Startup CFO started working with Build38 in 2021, supporting the company as a strategic finance partner across different stages of growth.
From the beginning, the work went far beyond the traditional external CFO role. The company needed consolidated reporting, KPI analysis, financial planning, cashflow control and investor communication.
With three entities across different countries and an expanding business, having reliable, structured financial information was key to supporting strategic decisions.
— 02 · WHAT WE DID
Turning the finance function into the source of truth
At The Startup CFO, we took on a central role in Build38’s financial management, generating the data and analysis the company needed to operate, report and make decisions.
Over the years, we helped prepare materials, defend scenarios, structure information and support key meetings with investors and the board. In practice, the finance function became the company’s financial source of truth.
That accumulated work meant that, when the time came for a corporate transaction, the financial information was ready, understood and prepared to be defended in front of third parties.
Consolidated reporting
Development and monitoring of consolidated financial reporting for the group’s three entities, with clear information for management, board and investors.
KPIs and planning
Recurring analysis of KPIs, business evolution, margins, clients, cashflow and financial scenarios to support decision-making.
Transaction support
Data room preparation, Q&A sessions, communication with buyer and advisors, and support on key negotiation items.
— 03 · CORPORATE TRANSACTION
An acquisition that put the numbers to the test
In January 2026, Build38 announced its acquisition by an international company specialized in cybersecurity. For the company, it was a major milestone. For the finance team, it was a direct test of the quality of the work carried out over the years.
All the information shared with the buyer, from projections to cashflow evolution, client-level detail and product-line margins, came from the models, reports and processes built throughout the collaboration.
The Startup CFO also led the financial due diligence, from preparing the information to Q&A sessions, explanations and direct communication with the buyer and the firm in charge of the analysis.
— 04 · RESULTS
A transaction closed on a solid financial foundation
Acquisition 2026
Transaction announced with an international cybersecurity company
Due diligence
Financial preparation, Q&A and communication with buyer and advisors
Negotiation
Support on NWC, waterfall and key financial closing items
The Build38 case reflects the value of building a solid finance function long before a strategic transaction takes place. When the data is properly structured, understood and validated, the company can face demanding processes with much greater clarity.
This case shows how the external CFO role can evolve into a key piece during decisive moments. In an M&A transaction, the numbers do not just explain the company: they also help defend its value.
