project 01 / 09

The body was never the problem

Turning the four menstrual cycle phases into a calendar you can actually export and use to plan your life around it.

Benchmark AnalysisMarket ResearchProduct StrategyBrand Identity DesignContent StrategyUX WritingPrompt EngineeringAI Web DevelopmentVibe CodingMiroClaude CodeVercel

challenge

The menstrual cycle app category is crowded and fragmented, and almost all of it points the same way: prediction. Fertility windows, period reminders, symptom logs. Very little of it helps someone understand how the four phases affect focus, energy, and work. And the tools that do go deeper ask for a lot of personal data in exchange. I wanted a small, useful thing that sat in that gap: phase education tied to the place people already plan their lives, the calendar, with nothing stored and nothing sent anywhere.

my role

Sole creator. Strategy, market research, product definition, brand, content, and the AI-assisted build and deployment. I owned it end to end.

methodology

Three phases, mirroring the Miro board I built before writing a line of code.

01Plan: benchmarked existing cycle apps and calculators, mapped the functionality an MVP actually needed, and settled the layout references and deployment path before committing to a direction.

02Discovery: defined the business idea to build literacy around the four phases and how each one affects mental, physical, and emotional well-being, plus how to adapt habits and work styles around them. Wrote the drive and character of each phase: menstrual, follicular, ovulatory, luteal. Ran the market research that produced the core finding: the category splits between privacy-first minimalism and feature-heavy suites, and the work and leadership angle is almost entirely unaddressed.

03Create: turned discovery into a PRD and a minimal brand system. Wrote the manifesto and all interface copy in English and Portuguese. Translated the brand guidelines, content architecture, and layout benchmarks into specific, constrained prompts, then built and shipped the site with an AI coding tool, keeping the calculation logic fully client-side so nothing a user types leaves their browser.

outcomes

→Shipped a live, bilingual, fully responsive product in four days, alongside other work.

→More than 50 views in two days.

→Privacy-first by construction: the phase calculation runs entirely in the browser, with no server, no account, and no storage.

→Real export, not a screenshot. Users download an .ics file and import their four phases into Google Calendar, Apple Calendar, Outlook, or Notion.

→Every phase description and the calculation basis is grounded in published research, cited on the page.

→Reused the process from my portfolio build (a human source of truth first, AI as the execution tool) and confirmed it holds for a product with real logic, not just a static site.