Christian Freischlag digital-thinking

Engineer reliable AI systems that run in production.

AI architecture reviews · Technical due diligence · MLOps · Agentic engineering

Portrait of Christian Freischlag

I’m Christian Freischlag, a Machine Learning/AI Engineer with a decade of experience. I help startups move AI from proof-of-concept to production, with the architecture, MLOps discipline and observability to hold up under real traffic, real budgets, and real failure modes. For founders, CTOs and investors I also take an independent look at systems that already exist: is it solid, will it scale, and what should happen next?

The first call is a free conversation. Usual response within 48 hours.

What a review looks at The five questions I hear most, and where in the system the answer sits.
Data Retrieval Model Serving Evaluation Monitoring 1 2 3 4 5
  1. Data Do we own data others can’t simply get?
  2. Model Our own tech, or a thin layer over someone else’s model?
  3. Evaluation How do we know a change made it better?
  4. Serving What does one request cost, and what happens at 10x traffic?
  5. Monitoring Who notices when quality drops, and how fast?
Background
10+ years in software and ML engineering. Lead ML Engineer at Chrono24, then Manager NLP & AI at KPMG.
Today
Main job: MLOps Engineer at Auction Technology Group. Consulting on the side, with limited capacity.
Works with
Founding engineers, CTOs and product leads. VCs and their portfolio companies.
Where
Karlsruhe, DE. Remote-friendly, in English or German.

Services

Where I can actually help.

Four ways to work with me, all based on things I’ve shipped in production, repeatedly. Scoped up front, limited in time, and done by me personally.

AI Architecture & Production Review

For founders and CTOs

An independent look at an AI/ML system that is in production or about to be. Does it stay stable under load and budget pressure, are the right primitives in place (ML, LLMs, embeddings, retrieval, agents), and what needs fixing first?

When it makes sense

  • The prototype convinced everyone. Now it has to survive real traffic, real budgets, and real failure modes.
  • Quality, latency or the inference bill is going the wrong way, and nobody can say exactly why.
  • A bigger build, a re-platforming or a key hire is coming up, and you want a second opinion first.

What I look at

  • Architecture and data flow, from system diagram to deployed service
  • Evaluation: is quality actually measured (offline, A/B tested)?
  • Serving, latency and cost per request
  • Observability, drift monitoring, failure modes
  • Reproducibility, CI/CD, test coverage that means something
  • Build vs. buy, and whether the team can run it

What you get

A written report with prioritised findings and a session with your team to go through it. Concrete enough that your engineers can start on the first item the next day.

Format

Usually two to three weeks, part-time. I read code, docs and dashboards, and talk to the people who build and run the system.

AI Technical Due Diligence

For VCs and investors

A technical assessment of a company whose value depends on its AI. Does the technology match the pitch, and what would it take to scale it?

When it makes sense

  • The AI is the product, and you need to know how much of it is real.
  • Own technology, or a thin layer over someone else’s model? You want to know before you sign.
  • A portfolio company’s AI roadmap keeps slipping, and you want an independent view on why.

What I look at

  • What’s behind the claims: models, data, evaluation
  • Defensibility: what’s hard to copy and what isn’t
  • Scalability and what inference costs per unit
  • Engineering practice and depth of the team
  • Dependencies and risk: model providers, OSS licences, security

What you get

A short memo an investment committee can read: findings, red flags, open questions for the founders and a clear overall call. With realistic feasibility calls, and pushback where the pitch over-promises. The technical detail goes in the appendix.

Format

Under NDA, timeline agreed up front. Based on documents, code access where possible, and conversations with the technical team.

Technical Advisory

For founding engineers and CTOs

A sparring partner for a few hours a month. My philosophy: fast prototypes for validation, robust system engineering for production. Use the right tool, not the existing.

Typical topics

  • Architecture decisions
  • Build vs. buy
  • Roadmap
  • Design reviews
  • Interviewing the ML engineers you want to hire

Agentic Engineering Consulting

For engineering teams

Practical coaching and architecture for teams adopting agentic coding tools — Claude Code, Cursor, Copilot, custom agents. When implementation gets faster, everything piles up before and after it: in decisions, reviews and approvals. So most of the work is around the agent. Same engineering rigour applied to a brand-new toolchain, so you don’t end up with code nobody on the team really understands anymore.

Around the agent

  • CI integration and automated PR review
  • Test generation and QA
  • Refactor agents
  • Guarded production changes: who signs off on what
  • Observability that closes the verification loop. An agent that can read logs is worlds better than one that can’t.

Not my thing: full-time contracting, or bringing a whole team to build the product. If that’s what you need, I’ll tell you in the first call, and I usually know who to ask.

Work

My engineering work.

What I did before, and still do, bundled by topic instead of by employer. This comes from my jobs as an employed engineer, not from client projects. It’s here as background; no endorsement by these companies is implied.

ML/AI projects

From the idea to production. For example the Chrono24 Watch Scanner: custom image classification models (CNNs, TensorFlow) and a dedicated, auto-scaling AWS architecture capable of handling 20,000+ daily requests at peak. Or an end-to-end anti-fraud system from before the LLM era, using SVMs and Random Forests alongside LSTMs and Transformers to analyse behavioural patterns and linguistic cues. And at KPMG: LLM-agent-based evaluation of document extraction results, to raise the straight-through processing rate.

Chrono24 · KPMG

ML platform & MLOps

Architected and deployed end-to-end ML platforms: on Docker, Airflow, Terraform and Snowflake, and as a containerised NLP SaaS platform (Python · .NET · Kubernetes · RabbitMQ). With everything that belongs to it: dependency management, build system, a DevOps / CI/CD initiative and a performance & scaling roadmap. ML platform and MLOps are also what I’m responsible for in my current job.

Chrono24 · KPMG · Auction Technology Group

Search, recommenders & GenAI

Integrated Learning to Rank within Solr, with rigorous NDCG benchmarking to quantitatively prove and optimise search relevance. Recommendation architectures from classic collaborative filtering through transformer-based systems, including the NLP-inspired deep recommender presented at Rework AI London 2022. Led the internal adoption of LLMs, OpenAI APIs and vector search, moving from experimental prototypes to productionised generative use cases.

Chrono24

Operations & compliance

Escalation engineer for production incidents, root-cause analyses and post-mortems. Owned enterprise compliance topics (OSS licensing, CVE and vulnerability management) at the security bar expected at a Big Four firm.

KPMG

Hiring & leadership

Technical hiring lead and mentor: interviewing, onboarding and professional development of Machine Learning and Data Engineering teams, at Chrono24, at KPMG and in my current job. Led a cross-functional team of 5 to 10 across ML, backend and DevOps.

Chrono24 · KPMG · Auction Technology Group

Feasibility & strategy

Technical SME for NLP / ML / GenAI in strategic sales and management rounds, supporting proposals with realistic feasibility calls and building trust by pushing back on over-promised commitments. Advised leadership on ML prioritisation and topic selection in line with business goals.

KPMG · Chrono24

Consulting work

Advisory, confidential.

US Luxury eCommerce Platform

Advising the founding engineers on the AI foundations of a luxury eCommerce platform (US). Helped shape a hierarchical, recommendation-friendly catalog and listing data model built to outlast the first wave of features, and guided the integration of visual embeddings into retrieval so the platform can surface similar items across a highly aesthetic catalog — keeping the production ML stack debuggable.

Applied AI Architecture Advisor · 2025–2026

Marketplace, ClimateTech

Consulting and AI-assisted implementation.

Agentic Engineering and Software Architecture · 2025–2026

Employers

Auction Technology Group (now), KPMG, Chrono24, CERN

Education

M.Sc. Machine Learning (2016–2018) and B.Sc. Computer Science (2011–2015), Karlsruhe University

Speaking

“NLP-inspired deep recommender for out-of-catalog items”, RE•WORK AI Summit, London 2022

Certifications

Learning to Rank (2024) and Solr Search (2023), Opensource Connections

How it works

How an engagement runs.

  1. First call

    A free conversation, about 30 minutes. You describe the problem, and I’ll tell you honestly whether I’m the right person for it.

  2. Scope

    We write down the questions to answer, the access I need, timeline and price. Before any work starts.

  3. The work

    I read code, docs and dashboards, and talk to the people who build and run the system.

  4. Findings

    Written down, prioritised and walked through together. Clear enough for management, detailed enough for the engineers.

Still an engineer

I’m an engineer and want to stay one. Consulting runs alongside my main job: part-time and only a few engagements at once, but advice from someone who builds and runs this stuff every week.

Independent

No agency behind me, no follow-up project I need to sell. “It’s fine, leave it” is a valid result.

Confidential

NDA is standard. I don’t take work that conflicts with my employer.

Describe the problem in a paragraph.

I’ll tell you honestly whether I’m the right person for it — and, if I’m not, who is. Usual response within 48 hours. The first call is a free conversation.

Christian Freischlag Machine Learning/AI Engineer

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Helps, but isn’t required

  • Your current stack & where it hurts
  • Team size & in-house ML capability
  • What you’ve already tried

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