Best ML Development Services

XenonStack vs Existek: full comparison for 2026

Last updated: July 2026

Quick verdict

XenonStack (4.4/5) edges ahead of Existek (3.9/5) overall. XenonStack is the better choice for companies building agentic AI or real-time data platforms that want a specialist rather than a general IT outsourcer.. Existek is the stronger option for mid-market companies wanting a Clutch-recognized offshore development firm with AI as an add-on service.. The right choice depends on your project size, budget, and required tech stack.

XenonStack vs Existek: head-to-head summary

Criterion XenonStack Existek
Founded 2016 2012
HQ Mohali, India Bucharest, Romania
Team size 50–100 50–249
Rating 4.4 / 5 3.9 / 5
Best for Companies building agentic AI or real-time data platforms that want a specialist rather than a general IT outsourcer. Mid-market companies wanting a Clutch-recognized offshore development firm with AI as an add-on service.
Pricing model Project-based, retainer Project-based, dedicated team
Min. engagement Not published $25,000+
Primary tech stack Kubernetes, Apache Kafka, AWS Python, TensorFlow, AWS
Industries served FinTech, Manufacturing, Telecom, Retail & E-commerce Healthcare, Oil & Gas, Education, Business Intelligence

XenonStack vs Existek: overview

XenonStack

XenonStack was founded in 2016 by Navdeep Singh Gill and is based in Mohali, India, operating as a technology consulting company centered on real-time data, generative AI, and agentic AI platform engineering. The company has grown from roughly 63 employees in 2023 to about 97 in 2026 and holds AWS, Azure, and Google Cloud partner status, alongside membership in the Cloud Native Computing Foundation and LF AI & Data. Its bootstrapped, revenue-funded growth (reported ~$3.8M ARR) suggests a stable but still relatively small operation for enterprise-scale programs.

Existek

Existek was founded in 2012 and operates with a 50–249 person team split across Bucharest, Romania and Vinnytsia, Ukraine, delivering custom software development, dedicated team staffing, and AI development services for clients in business intelligence, healthcare, oil & gas, and education. The company has been recognized by Clutch as a top developer in both Ukraine and Romania and holds a near-perfect 4.9 rating on the platform, with hourly rates of $50–$99/hr and a minimum project size of $25,000+. Its AI services page is comparatively general, offering less publicly documented technical specificity than boutique ML specialists in this list.

Services and capabilities: XenonStack vs Existek

Capability XenonStack Existek
Custom ML Models
Computer Vision
NLP
MLOps
Generative AI
AI Consulting

Tech stack comparison: XenonStack vs Existek

Framework / platform XenonStack Existek
TensorFlow N/A
PyTorch N/A N/A
AWS
Azure N/A
Google Cloud N/A
LangChain N/A
Hugging Face N/A N/A
Kubernetes N/A

Pricing comparison: XenonStack vs Existek

Criterion XenonStack Existek
Minimum engagement Not published $25,000+
Engagement models Project-based, Retainer, Dedicated team Project-based, Dedicated team
Rate transparency Not public Minimum disclosed
Price tier Mid-market Mid-market

Target audience comparison: XenonStack vs Existek

Dimension XenonStack Existek
Best company size Startup to mid-market Startup to mid-market
Best industries FinTech, Manufacturing, Telecom Healthcare, Oil & Gas, Education
Best use cases Enterprise needs a real-time data platform feeding downstream ML models., Company is building agentic AI workflows and needs specialist platform engineering, not just model development. Mid-market company wants a Clutch-recognized offshore vendor with a $25K+ entry point for an AI-adjacent project., Oil & gas or business intelligence company needs custom software plus AI/ML from a single vendor.
Typical project type Project-based Project-based

XenonStack vs Existek: pros and cons

XenonStack
+ Multi-cloud partner status across AWS, Azure, and Google Cloud gives flexibility on platform choice rather than pushing a single vendor stack.
+ Bootstrapped and profitable growth trajectory (reported ~$3.8M ARR) signals operational stability without dependence on external funding rounds.
+ Cloud Native Computing Foundation and LF AI & Data membership reflects genuine open-source platform engineering involvement, not just marketing claims.
+ Specialization in agentic and real-time AI platform engineering is a differentiated niche versus generalist ML shops.
- Team size of roughly 97 (2026) is small relative to the scale of enterprise real-time data platform programs it targets.
- Conflicting HQ reports (Mohali, India vs. Dubai, UAE across sources) make it worth confirming the primary legal entity before contracting.
Existek
+ 4.9 near-perfect Clutch rating with top-developer recognition in both Ukraine and Romania.
+ $25,000+ minimum project size is more accessible than large enterprise-only vendors like EPAM.
+ 12+ years of operating history (since 2012) with dual-country delivery presence.
+ Serves niche industries (oil & gas, business intelligence) less commonly covered by boutique AI specialists.
- Publicly available technical detail on Existek's specific AI/ML methodology is thinner than boutique specialists like Neurons Lab or Provectus.
- AI development is one of several service lines (custom software, staff augmentation) rather than the firm's exclusive focus.

Who should choose XenonStack?

XenonStack is the right choice for companies building agentic AI or real-time data platforms that want a specialist rather than a general IT outsourcer..

Multi-cloud certified (AWS, Azure, GCP) platform-engineering specialist for real-time and agentic AI.. Minimum engagement starts at Not published. Works best with clients in FinTech, Manufacturing, Telecom, Retail & E-commerce.

Who should choose Existek?

Existek is the right choice for mid-market companies wanting a Clutch-recognized offshore development firm with AI as an add-on service..

4.9 Clutch rating with dual Ukraine/Romania Clutch top-developer recognition and a $25,000+ accessible entry point.. Minimum engagement starts at $25,000+. Works best with clients in Healthcare, Oil & Gas, Education, Business Intelligence.

Decision matrix: XenonStack vs Existek

Your situation Recommended choice
You need full-ownership delivery on a defined project scope Both offer fixed-price models
You need a large dedicated team for an ongoing programme XenonStack
Your budget is at the lower end Compare: XenonStack (Not published) vs Existek ($25,000+)
You need specialist depth in a specific vertical XenonStack
You need production MLOps support after model launch XenonStack
You need consulting before committing to a build Existek

Use case fit: XenonStack vs Existek

Use case XenonStack fit Existek fit Winner
Enterprise needs a real-time data platform feeding downstream ML models. Strong Limited XenonStack
Company is building agentic AI workflows and needs specialist platform engineering, not just model development. Strong Strong Both equally
Mid-market company wants a Clutch-recognized offshore vendor with a $25K+ entry point for an AI-adjacent project. Limited Strong Existek
Oil & gas or business intelligence company needs custom software plus AI/ML from a single vendor. Limited Strong Existek
Fixed-scope ML build Limited Limited Both equally
Ongoing model retraining Limited Limited Both equally

Verdict: XenonStack vs Existek

XenonStack (4.4/5) is the stronger overall choice for most Machine Learning Development projects. Multi-cloud certified (AWS, Azure, GCP) platform-engineering specialist for real-time and agentic AI.. It is best for companies building agentic AI or real-time data platforms that want a specialist rather than a general IT outsourcer..

Existek (3.9/5) is the better choice when mid-market companies wanting a Clutch-recognized offshore development firm with AI as an add-on service.. If your situation matches those criteria, Existek is a competitive option.

Related comparisons

XenonStack vs Existek FAQ

Is XenonStack better than Existek?

XenonStack (4.4/5) scores higher overall, but "better" depends on your use case. XenonStack is better for companies building agentic AI or real-time data platforms that want a specialist rather than a general IT outsourcer.. Existek is better for mid-market companies wanting a Clutch-recognized offshore development firm with AI as an add-on service..

How do XenonStack and Existek differ in pricing?

XenonStack uses project-based, retainer pricing with a minimum engagement of Not published. Existek uses project-based, dedicated team pricing with a minimum engagement of $25,000+. Neither firm publishes a full rate card; a discovery call is required for project-specific quotes.

Which is better for enterprise: XenonStack or Existek?

Existek is the larger team and typically the better enterprise-scale choice. For very large programmes, verify team size and compliance coverage directly with each company before shortlisting.

What are the main differences between XenonStack and Existek?

XenonStack's primary differentiator is: multi-cloud certified (aws, azure, gcp) platform-engineering specialist for real-time and agentic ai.. Existek's primary differentiator is: 4.9 clutch rating with dual ukraine/romania clutch top-developer recognition and a $25,000+ accessible entry point.. They also differ in team size (50–100 vs 50–249), minimum engagement (Not published vs $25,000+), and primary industries served (FinTech, Manufacturing vs Healthcare, Oil & Gas).

Last reviewed: July 2026. Verify all details directly with each company before making a decision.