SPERO

SPERO

AI Reliability Engineering

Ship AI features you can actually measure.

Your LLM feature works in the demo. Then someone changes a prompt, the model provider ships an update, and nobody knows what broke until a customer does. I build the evals, regression tests and release gates that make AI behave like the rest of your software.

15+ years in QA and test automation 路 Master's in Computer Engineering 路 4-8 hours overlapping with any US time zone

Most AI features ship on vibes.

Prompt changes are blind.

Someone tweaks a system prompt to fix one case. Three other cases quietly break. No test catches it because there is no test.

Model updates change behavior.

Your provider ships a new version, or you switch to a cheaper model to cut costs. Output quality shifts and you find out from support tickets.

"Looks good to me" is the eval.

An engineer reads twenty outputs, they seem fine, it ships. That's not a quality process. It's a coin flip with extra steps.

What I build

AI Reliability Audit

A two-week review of your LLM features. I map failure modes, test your current prompts against real edge cases and hand you a prioritized risk report with a concrete fix plan.

Eval Suites & LLM Regression Testing

Golden datasets, automated evals (deterministic checks, calibrated LLM-as-judge, human review loops) and a regression suite that runs on every prompt or model change.

Release Gates in CI

Evals wired into your pipeline. A prompt change that drops quality below your threshold doesn't merge. Same for model swaps.

Agent & RAG Testing

Tool-call correctness, retrieval quality, hallucination checks, cost and latency budgets. Tested per step, not just on the final answer.

Test Automation for the rest of the product

E2E, API and integration testing with Playwright and modern tooling. Because your AI feature sits inside an app that also has to work.

Already have an eval tool? Good. I implement it.

Braintrust, Langfuse and promptfoo are great tools. A tool doesn't decide what to test, build the golden dataset, calibrate the judge against human reviewers or wire the gate into your release process. That's the work I do.

I'm tool-agnostic. If you already use one, I build on top of it. If you don't, I help you pick the one that fits your stack, and everything stays in your account.

Building an eval or observability tool? I'm open to implementation partnerships.

BraintrustLangfusepromptfooLangSmithDeepEvalRagasOpenAI EvalsYour own harness

How an engagement works

  1. 01

    Reliability review 路 30 min, free

    I look at one AI feature with you and tell you honestly whether I can help. If I can't, I say so.

  2. 02

    Audit 路 2 weeks, fixed price

    Failure mode map, baseline eval scores, risk report, fix plan. You own everything I produce, even if you stop there.

  3. 03

    Build 路 3 to 6 weeks

    I implement the eval suite and CI gates inside your repo, working with your engineers, not around them.

After the audit

The audit shows which of these comes next. Same core every time: evals, tests and release gates.

Model Migration Assurance

Pays for itself

Fixed project 路 2 to 3 weeks

Moving to a cheaper model or another provider? I run your golden dataset on both, compare quality, cost and latency per use case and tell you where it's safe to switch and where it isn't.

AI Red Teaming + Evidence Pack

Fixed project 路 paid quarterly retest

Prompt injection, jailbreaks, PII leaks, agent tool misuse. You get a test evidence report ready for security questionnaires, SOC 2, HIPAA and enterprise procurement. QA evidence, not a pentest.

Fractional AI Quality Lead

Monthly 路 defined deliverables

Your part-time head of AI quality until you hire one. I review prompt and model changes, maintain datasets, set metrics and train your team.

SPERO

Why teams work with me

I come from QA, not from AI hype.

15+ years breaking software before customers do. I treat LLMs as one more system that needs tests, metrics and gates.

A senior engineer, directly.

You talk to the person who writes the code. No account managers, no juniors learning on your repo.

Your time zone.

Based in Brazil, 4-8 hours overlapping with any US time zone. Daily async updates, calls when you need them.

You own the work.

Everything lives in your repo, in your CI, documented. No lock-in, no proprietary platform.

15+

years in QA and test automation

2 weeks

from kickoff to prioritized risk report

0

API keys needed to run my public eval harness in CI

100%

of the work delivered in your repo

Don't take my word for it. Read the code.

Every repository below is public. Clone it, run it and judge the engineering yourself before you book a call.

Models and tools I test with

OpenAIAnthropicGoogle GeminiOpen-source modelsLangChainLlamaIndexPlaywrightGitHub ActionsGitLab CICircleCI

Recommendations

What people I worked with say

Verify on LinkedIn

Douglas was our first software engineer in test hire at Olly Olly. He was instrumental in getting our testing discipline off the ground. Leveraging his years of experience in DevOps and Test Automation, Douglas helped guide the creation of our testing framework, which was challenging because there were no proven approaches for our stack. Without Douglas, our testing discipline would be severely behind. If you have a unique test automation problem to solve, Douglas has the skills and experience to analyze your situation and build a thorough, scalable solution.

Benjamin De Point

Software Engineering Executive

Managed Douglas directly 路 Mar 2026

Proximo hired Douglas when we were looking for a QA expert to help jump start a quality testing automation project for one of our platforms. I and the rest of the team were impressed with Douglas and brought him on. He was definitely the right choice, as he had us up and running in less than two months. He worked with existing team members and always kept in mind what we were trying to accomplish. He's also very pleasant and energetic, and our people liked working with him. I'd wholeheartedly recommend Douglas for any quality assurance work.

David Ricciardi

CEO of Proximo

Hired Douglas 路 Oct 2021

I had the pleasure of working with Douglas on our team. He consistently demonstrated exceptional attention to detail, a strong commitment to quality and an evangelist for agile best practices that significantly enhanced our product reliability. He is a true asset to any team, bringing not only his technical skills around automation, but also a collaborative spirit that makes working together a pleasure.

Devin Lam

Lead Product Manager

Worked on the same team 路 Apr 2024

I wholeheartedly recommend Douglas for the position of Quality Engineer. During our time working together, he not only excelled in executing quality assurance protocols but also actively contributed ideas for process improvements, displaying a proactive approach to problem-solving. His ability to analyze complex systems and identify potential areas for enhancement greatly contributed to our team's success. I am confident that Douglas will bring the same dedication, expertise, and collaborative spirit to any role in Quality Engineering.

Tapesh Nagarwal

Senior Specialist, Quality Engineer | Founder, TapQuality AI LLC

Managed Douglas directly 路 Apr 2024

I worked with Douglas for a few months during his time at Fabric. He has a lot of knowledge about quality systems and how to bring quality first thinking into your applications. He is great at coming up with new processes that are documented in detail about how you can improve quality and sets up process to measure and check the quality of engineering regularly. Douglas is also willing to take on new things and learn more about new tools and is a good team player!

Pranay Karnany

Manager at Fabric

Managed Douglas directly 路 Oct 2021

Douglas has a natural drive to solve problems. He is really focused and has a broad technical background in software engineering, ranging from dynamic programming and testing to data analysis. Besides that, he always shares his knowledge with colleagues, creating a learning environment wherever he is. If you have a tough problem that needs to be solved, it's better to call Douglas.

Gabriel Gomes

PhD | Applied Machine Learning | Signal Processing | Electrical Engineering

Worked with Douglas on different teams 路 Oct 2021

Douglas is an excellent collaborator. Always thinking ahead and proposing new ideas, he is a great team member. Our time working together was really fun.

Leonardo Kochake Gomes

DevOps Automation Engineer | SAFe庐 4 DevOps Practitioner

Worked on the same team 路 Oct 2021

An outstanding professional who spares no effort to deliver a final result of the highest quality.

Fernando Flor锚ncio da Mata

Owner at NIPN Neg贸cios Digitais

Reported to Douglas directly 路 Oct 2021

Start with the audit

AI Reliability Audit

Two weeks. Fixed price. A clear answer to "how reliable is our AI feature, and what do we fix first?"

From $4,500

  • Failure mode map of up to 2 AI features
  • Baseline eval scores on a starter golden dataset
  • Prioritized risk report
  • Implementation plan with effort estimates
  • 60-min walkthrough with your team
Book a reliability review

FAQ

Stop guessing whether your AI works.

30 minutes, one AI feature, an honest assessment.

Book a reliability review