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ZERO_OS / QUICK ACCESS

Navigate the lab.

10 results. Selected: Manifesto.

RECRUITER BRIEF. 01 / TECHNICAL PORTFOLIO

Zero.
Product engineer.

Seven systems across different domains, built from problem to operation: SaaS, mobile, quantitative fintech, AI automation, and multiplayer games.

Explore the cases

SNAPSHOT. 02 / A 30-SECOND READ

Breadth with evidence.

07
SYSTEMS
SEVEN STATIC CASE STUDIES
02
PUBLIC DOORS
AUTOWHATS + NEXO
04
LAYERS
INTERFACE / SERVICE / DATA / EDGE
04
QUALITIES
BOUNDARIES / STATE / FAILURE / SIGNAL

QUALITY GATE. 03 / THE SITE IS ALSO A BUILD

Make an impression. And hold up.

Automated contracts accompany the interface. The values below reflect the latest validated cut, not indicators simulated in the browser.

01 / TYPE SYSTEMPASS
STRICT

TypeScript as a contract

Strict types, exact optionals, and defensive indexed access block ambiguity before the build.

02 / STATIC ANALYSISPASS
0 WARN

Lint without amnesty

ESLint and JSX/ARIA rules fail on errors and warnings alike; accessibility is never postponed.

03 / CONTRASTPASS
84 AA

Measured readability

Audited information pairs pass WCAG AA, with dedicated adaptations for contrast and forced colors.

04 / PRIVACYPASS
0 TRACK

No hidden observer

No analytics, cookie, remote font, or background connection enters the institutional experience.

05 / INTERACTIONPASS
27.7 KB

Bounded complexity

Nine custom modules remain isolated and below the 28 KB budget; useful content arrives first.

06 / DISCOVERYPASS
36 URL

Findable and readable

Sitemap, JSON-LD, RSS, canonicals, and JSON Schema connect pages, cases, writing, authorship, and contract.

REVIEWED / AUG 22 2026INSPECT PORTFOLIO.JSON

CAPABILITY MAP. 04 / RESPONSIBILITY

Four layers. One flow.

  1. L1

    Interface & product

    Responsive experiences, complex state, and flows that make the domain visible to operators.

    • React 19
    • Next.js 16
    • React Native
    • Vite
    • TypeScript
    ERP, Auto Whats, AI_VTT, NEXO, Castle Wars, and Our Home
  2. L2

    Services & realtime

    APIs, gateways, and isolated processes that protect boundaries and keep interactions synchronized.

    • ASP.NET Core
    • Fastify
    • Node.js
    • Socket.IO
    • Supabase Realtime
    Renaissance, Auto Whats, Castle Wars, and Our Home
  3. L3

    Data & state

    Relational persistence, cache, event series, and authoritative rules designed around each use case.

    • PostgreSQL
    • Redis
    • ClickHouse
    • Firebase
    • Supabase RLS
    seven architectures with different state strategies
  4. L4

    Integrations & intelligence

    Models, voice, messaging, payments, and external APIs treated as capabilities with explicit limits.

    • AI agents
    • Baileys
    • Asaas
    • ZapSign
    • ProfitDLL
    automation, generative RPG, fintech, and SaaS operations

PROJECT INDEX. 05 / SEVEN SYSTEMS

Each project, a boundary.

Summary of seven projects, stack, stage, and primary technical decision.
CASEPROJECT / DOMAINSTACKSTAGECORE DECISION
01Project RenaissanceQUANT / FINTECH.NET 10 / ASP.NET Core / PostgreSQLV1 / SHADOW + PAPERRun ProfitDLL in its own process and keep live execution behind explicit gates; shadow and paper are the defaults.
02ERPOPERATIONS / SAASReact / Vite / FirebaseOPERATIONAL BASEModel the business flow first and treat payments, signatures, and communication as replaceable integrations.
03Castle WarsSTRATEGY / GAMEReact / Node.js / Socket.IOREALTIME PROTOTYPEValidate the realtime loop in memory and declare persistence as a gap instead of pretending the infrastructure is ready.
04Auto WhatsAUTOMATION / AINext.js / Fastify / PostgreSQLSAAS ONLINETreat AI as a per-conversation controllable mode and keep human handoff as a first-class product path.
05AI_VTTRPG / GENERATIVE GAMETypeScript / PostgreSQL / Voice AIVERTICAL SLICESeparate probabilistic narration from deterministic resolution; AI proposes fiction and the system validates actions.
06Desafio OnlinePUZZLE / SOCIAL GAMENext.js 16 / React 19 / PostgreSQLPLAYABLE MVPKeep solutions and progression authoritative on the server; the browser receives only the state required for the current stage.
07Our HomeMOBILE / HOUSEHOLDExpo SDK 57 / React Native / TypeScriptiOS MVP 1.0Keep authorization and critical transitions close to the database; the app sends intents and reconciles the projection through Realtime.

OPERATING SYSTEM. 06 / HOW I SHIP

From the problem to the next signal.

  1. 01

    Hypothesis

    A question good enough to deserve time, money, and risk.

  2. 02

    Execution

    A prototype in the real world—small, imperfect, and early enough.

  3. 03

    Outcome

    Open data: costs, decisions, wins, failures, and what happened.

  4. 04

    Learning

    The test ends. Experience returns to the system, and the next one begins.

INTERVIEW LENS. 07 / WHAT TO EVALUATE

Four signals to explore.

  1. 01

    System design

    Boundaries, authoritative state, consistency, idempotency, and failures are treated as product decisions.

  2. 02

    End-to-end delivery

    The same reasoning crosses interface, service, data, integration, operations, and the next iteration.

  3. 03

    Applied AI

    Models enter with context contracts, policy, deterministic validation, fallback, and a human in the loop.

  4. 04

    Product judgment

    Scope seeks the smallest flow capable of producing a signal without hiding gaps behind polish.

NEXT STEP. 08 / TECHNICAL CONVERSATION

Have a hard problem?

Direct contact remains optional and is never replaced with fictional data. In the meantime, every case is open for inspection in this portfolio.

CONTACT / PENDINGMeet Zero