Twelve years running marketplace operations across nine countries. Everything here is the models I kept rewriting from scratch at every new job. Publishing them means I never have to build them a third time — and neither does the next operator who inherits the seat.
I'm Everton Paula. My background is quality engineering out of aerospace and automotive, with a Lean Six Sigma Master Black Belt, followed by about a decade running operations inside marketplaces at multi-country scale. Most of that work is the same shape whether the marketplace moves parcels, people, or food: build the process before you hire against it, make performance visible so accountability does not depend on your mood, and design tripwires so quality does not break before you notice.
The public bio here is short by design. This is an artifact of the work, not a résumé. If you want the résumé conversation, I'm on LinkedIn.
Every operations leader I know carries a folder of spreadsheets from job to job. Surge calculator. Chargeback tracker. Vendor scorecard. Workforce forecaster. Driver performance sheet. Escalation flowchart. We rebuild them every two years because the last version belongs to the last employer.
The toolkit is a bet that if I put the calculators I kept rebuilding into single-file HTML under an MIT license, other operators can stop rebuilding them too. They live in the browser, phone home nowhere, need no signup, and survive any framework change because there is no framework.
The case studies page is what I would actually read first if I were you. Twenty-two anonymized stories of when each tool moved a real operational number, with setup, problem, what surfaced, and outcome.
Tools ship when a real operator conversation surfaces a gap that fits the toolkit's frame. There is no schedule. The roadmap tracks what is planned and what got de-scoped and why.
Nothing in the toolkit tracks you, sends analytics anywhere, or requires an account. If you find a bug or want to suggest a feature, open an issue on GitHub. If you fork it and build something interesting, I'd like to see it.