Fractional CTO

Technical ownership, without the full-time hire

I'm Saša Tančev, founder and CTO of Smartnet Technologies, and Fractional CTO to companies that need a CTO's judgement and an engineering team that can act on it. 30+ years in software, 20+ leading engineering organisations.

350,000+
Users on a platform I architected and ran in production
<3%
Consultation failure rate at peak load
25+
Senior engineers in the company I founded
30+
Years in software, 20+ in technical leadership
CET
4h+ daily US East Coast overlap
The role

What I take ownership of

Not a monthly advisory call. Accountability for the technical outcome.

Architecture from zero to production

Target-state architecture, decision records, environment topology, and a production-readiness roadmap that names the gaps instead of hiding them. That means monitoring, backup and recovery, rollback, and disaster recovery.

Azure cloud ownership

Infrastructure design, IaC, identity and access, network isolation, secret management, CI/CD, cost and scaling, from first provisioning through production operations and incident response.

Security, compliance & data protection

OAuth 2.0 / OpenID Connect, RBAC and managed identities, webhook validation, auditability, and GDPR-conscious handling of clinical and customer data.

Engineering team & delivery practice

Building and running cross-functional teams across backend, web, mobile, QA and PM. Architectural standards, delivery practices, quality expectations. With or without a Smartnet team attached.

Technology selection & due diligence

Build-versus-buy decisions across cloud, identity, real-time communications, payments, AI and mobile, judged on security, scalability, operational complexity, vendor lock-in, maintainability and total cost.

AI, real-time and IoT/OTA systems

Where the hard parts live: PII anonymisation ahead of LLM processing, provider-agnostic AI layers, video and chat at scale, and controlled software delivery to fleets of devices.

The difference

Most fractional CTOs advise. I can also deliver.

I founded and lead Smartnet Technologies, a 25+ engineer nearshore company in Niš, Serbia, built entirely on referrals. 80%+ of our engineers hold MSc or BSc degrees in Computer Science. That means a roadmap I own does not have to wait for you to hire.

You can engage me with a Smartnet delivery team behind the plan, or purely as your CTO, working alongside engineers you already have. Both models are on the table, and I will tell you honestly which one your situation calls for.

My background is engineering, not management theory. I still design the architecture, review the code, own the deployment pipeline, and get the call when production breaks.

Track record

Current and past mandates

Every claim above comes from one of these. Most have a published case study.

Eclipse hawkBit OTA Update Platform on Azure

2026 – present

Fractional CTO and platform architect for an industrial IoT client in Germany. Controlled software delivery to Linux and future Windows devices, built on Azure Container Apps, MySQL Flexible Server, Key Vault, Entra ID, Bicep, and an automated 14-scenario DDI acceptance suite. Proof of concept to production readiness.

VetCloud, veterinary telemedicine & EHR

2018 – present

Acting CTO for the platform's architecture, real-time layer and AI. Designed the GDPR-compliant reporting layer. PII anonymisation, then LLM summarisation, deliberately provider-agnostic across ChatGPT, Claude and Azure AI. Report-writing time cut by 56%.

PawSquad, part of IVC Evidensia

2020 – 2026

Fractional CTO to a UK veterinary telemedicine service inside one of Europe's largest veterinary groups. Owned the end-to-end architecture and personally built and operated the full Azure estate across isolated DEV, QA, UAT and PROD. Scaled to 350,000+ pet owners and 120+ veterinary professionals at under 3% consultation failure rate.

ProfitOptics, Inc. (USA)

2018 – present

Software development partner leading Smartnet's teams across a rolling portfolio of B2B platforms for US enterprise clients, covering quoting and pricing engines, contract management, AI-assisted support over Salesforce, Snowflake, SAP and MuleSoft, and AWS ETL pipelines.

Workango & WorQeez (UK)

2014 – 2019

Co-founder and CTO of a UK HR-tech startup. Architected a fully cloud-based, highly available jobs platform on Azure, with real-time notifications, background ETL workers, and integrations with the largest UK and global job portals.

Technology

Where I'm hands-on

Not a list of things I've read about. This is what I design, review and operate.

Cloud (Azure)
App Service · Container Apps · Azure SQL · MySQL Flexible Server · Key Vault · Managed Identity · Entra ID · RBAC · VNet · Bicep · CI/CD · isolated DEV→PROD
Backend
C# · .NET 10 (LTS) / ASP.NET Core · EF Core · REST & OpenAPI · OAuth 2.0 / OIDC · Hangfire · Redis · multi-tenant architecture
Real-time
Twilio Video · SignalR · WebRTC · virtual queues & intelligent routing · session monitoring and recovery
AI / LLM
PII anonymisation pipelines · provider-agnostic LLM summarisation · document AI · embedding vectors and vector storage
IoT / OTA
Eclipse hawkBit · SWUpdate · DDI · signed artifacts · staged rollouts · Docker
Data
SQL Server & T-SQL · MySQL 8.4 · ETL pipeline design · Snowflake · Python / Pandas
Direction
Angular · React · TypeScript · Flutter · native iOS and Android. I set the direction, the team writes the code
Engagement

How we'd work

Fractional CTO

Typically 1–3 days per week, remote, CET. Ongoing ownership of architecture, cloud, security and the engineering practice, with or without a Smartnet delivery team.

Short-form mandates

Technical due diligence, architecture review, or a production-readiness assessment, scoped in weeks, not quarters, with a written verdict you can act on.

Evaluating a fractional CTO?

Tell me what you're building and where it's stuck. The quickest way to start is a short call.

Let's talk →