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Provenly
Proof profile

Tomás Ferreira

Ships first versions. Ten years of other people's zero-to-ones.

Remote (Europe)CV title: Freelance DeveloperJoined 7/31/2026
3
Verified proofs
3
Unverified claims
1
Work samples
66
Best role fit

Verified skills

Challenge-verified ×1.0 Self-claimed ×0.3 No evidence ×0

Each of these was earned on a timed challenge and scored against a rubric that was published before the challenge started. The work is attached — you can read it.

API & Systems Integration
Challenge-verified7/31/2026
Level 4Leading

Sets integration patterns and builds abstractions that make correct handling the default for other engineers.

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Level 4 — idempotency, retry scoping, Retry-After handling, and a feedback-loop observation.

Debugging & Diagnosis
Challenge-verified7/31/2026
Level 3Independent

Diagnoses failures where the error is misleading, tests the cheapest hypothesis first, and verifies the root cause before fixing.

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Found both defects and traced them to a common root.

Code Review & Judgment
Challenge-verified7/31/2026
Level 3Independent

Ranks findings by severity, catches security and data-integrity issues, and writes feedback the author acts on.

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Severity-ranked fixes with a mechanism-level verification plan.

Claimed, not yet verified

Self-reported — the same standing as anything on a CV. Shown here for completeness and clearly separated, because a verified section only means something if the unverified one is honest.

most for founders who had a rough idea and no technical team. I'm the person who works out what to build when nobody can tell you
Three of those became real companies
founders who had a rough idea and no technical team

Work samples

Unedited submissions, with the rubric score attached.

Closest role fits

Scored against published role specs. Every number is itemised on the role page.

This profile is evidence, not a CV. Anything marked verified can be checked by reading the work.

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