The specialist
Two decades of enterprise data work,
applied to litigation
The engineering foundation
Sergio de Sousa is a senior backend engineer with more than twenty years of experience designing, stabilising, and evolving data-intensive systems in some of Canada's most demanding technical environments — banking, telecommunications, and large-scale retail logistics. That career was built on a single discipline: making complex data correct, traceable, and useful under conditions where errors have real consequences.
At Scotiabank, Walmart Canada, and across telecommunications infrastructure serving millions of users, the work was never abstract. Systems had to be right. Data had to be consistent. Processes had to be documented well enough that another engineer — or an auditor — could follow every step. That standard was not optional in those environments. It became the only way of working.
The forensic application
Throughout that engineering career, a specific category of problem recurred: data prepared for investigative or legal purposes that fell far short of what those purposes required. Records presented without context. Chronologies assembled without rigour. Datasets delivered in forms that obscured rather than clarified the underlying facts. The technical work was frequently done by engineers who understood the data but not the evidentiary demands — and the result was material that could not withstand serious scrutiny.
The application was clear. The same discipline that enterprise data environments demand — chain of custody thinking, documented methodology, precision in the treatment of records, clarity in the presentation of findings — is exactly what electronic evidence work requires. SERSO Investigations is the formal expression of that application: engineering standards, brought to bear on litigation support.
Standards and approach
Every engagement is treated as a production system problem. Scope is defined precisely before work begins. Every action taken on evidence is logged, timestamped, and attributable. Findings are documented in a form that can be disclosed, explained, and defended — because evidence that cannot survive disclosure is not evidence.
Scope before work. Every engagement begins with a written scope of work agreed with counsel. Nothing proceeds without a clear and shared understanding of what is being done and why.
Chain of custody from first contact. Evidence handling is documented from the moment material is received. Every step is logged, timestamped, and attributable — because the integrity of the process is inseparable from the integrity of the evidence.
Findings delivered for direct use. Reports and evidence packages are structured for counsel's immediate use — without requiring a technical intermediary to interpret or translate the output.
Methodology available for disclosure. Nothing in the process is proprietary or opaque. Every step can be explained, disclosed, and defended — including under cross-examination.
Public engineering work
Sergio's published engineering work reflects the same standards applied privately to client engagements. Open-source modules authored under the PAUSE identifier SDS include production-grade data preparation and ETL tooling — public, documented, tested, and maintained to the same rigour as any production system.
Engineering work held to that standard does not become less rigorous when the downstream consumer is a courtroom rather than a database.
Published modules focused on data preparation, transformation, and ETL workflows. Production-grade, fully documented, with tests and maintained release history. Includes the Flat::* series for structured flat-file data handling.
metacpan.org/author/SDS →Languages
In matters where source materials, witnesses, or parties involve languages other than English, no intermediary is required. Sergio works directly in English, French, and Portuguese — with professional proficiency in Spanish.
Working on a matter involving electronic evidence?
Let's discuss what you need — and what your case requires.