RAFAEL CARDOSO / RCLABS

Backend engineering. Distributed systems.

I build backend services and data pipelines. At Synchro (2011-2024), I designed fiscal integrations and guided engineering teams. Below are my independent projects.

Selected work Read my resume

For recruiters, engineering managers, and technical interviewers evaluating my engineering work.

A closer look

Professional experience

Roles, contributions, and historical workload.

Selected engineering work

Implementation, failure modes, and regression coverage.

Source and tests

Code, test evidence, and verification gaps.

Professional experience

Synchro

Feb 2011 - Sep 2024

Software Analyst → Senior Staff Software Engineer

I designed fiscal integrations and guided teams of 3 to 8 engineers through architecture decisions and code reviews.

Historical employer work. The projects below were built independently.

Independent projects

Selected engineering work

Search, ingestion, network observations, and SQL change review. Implementation details and evidence live with each project.

Durable ingestion

Octopus

Scala / Cats Effect / PostgreSQL

Persisted ingestion, deduplication, leases, and outbox dispatch for event pipelines.

Workflow and live readings

Delivery may repeat. Saved progress and deduplication support replay across configured streams.

Retrieval & investigation

Atheros Search

Go / PostgreSQL / SolidJS

Semantic, keyword, and fused retrieval across source observations, with leased embedding workers.

Search documentation

Synthetic public sample. An observation does not confirm a current connection or device identity. Identity suggestions are review candidates.

SQL change review

Schema Migrator

Scala / Cats Effect

Ordered SQL-file validation, shortened dry-run previews, and selected catalog checks. Column definitions and nullability are outside drift comparison scope.

Migration walkthrough

SQL-file snapshots preserve source files and checksums. They do not back up database data. The sample executes no SQL.

Network observations

RCLabs VPN / Proxy

Rust / WireGuard

WireGuard ingress, transparent proxy handling, classification, and audit-event publishing.

Proxy walkthrough

Classification is a review aid. It does not prove intent, prevent a connection, or cover traffic outside the configured path.

Public Search, Migrator, and VPN / Proxy samples use synthetic data. Octopus operational readings come from its runtime feed.

Source & tests

The implementation stays visible.

Review failure handling, regression coverage, and known gaps beside the source. Source links do not certify a current passing test run.

View source on GitHub

Worked examples

Technical guides

PostgreSQL migration dry runs

Discovery, validation, and an offline preview before execution.

PostgreSQL schema drift

Expected definitions, observed catalog state, and review boundaries.

Migration checksum mismatches

File integrity, snapshot changes, and what they establish.

Suspected rogue access points

Wireless observations with site and authorized-network context.

Wi-Fi deauthentication indicators

Time windows, capture scope, and corroborating evidence.

Hybrid search for observations

Term, vector, and fused retrieval on synthetic records.

All guides

Before you start

Do the samples use real data or change anything?

The Search, Migrator, and VPN / Proxy samples use synthetic records in your browser. They execute no SQL, open no VPN connection, and change no production systems. Octopus separately loads public production metrics.

How do the projects fit together?

The proxy and sensor produce observations. Octopus records and processes them. Atheros Search indexes and retrieves them. Schema Migrator is companion tooling for reviewing SQL changes.

Can I discuss my own data or deployment?

Email me with the project, environment, and constraints you want to discuss. The contact page has project-specific email links.