# Leonardo Raponi — Application Support Engineer

> Application Support Engineer with ~10 years across IT infrastructure, networking, and SaaS platform support. Specializes in disciplined, evidence-based troubleshooting, root cause analysis (RCA), and designing internal tooling and automations that permanently eliminate recurring operational failures.

## Quick Facts
- **Name:** Leonardo Raponi
- **Primary Title:** Application Support Engineer
- **Alternative Titles:** Technical Support Engineer (L2/L3), Systems Support Engineer
- **Location:** Sorocaba, São Paulo, Brazil (UTC-3)
- **Availability:** Open to remote opportunities worldwide (async-first, full-time/contract)
- **Languages:** Portuguese (Native), English (B2 Professional Working Proficiency — strong written/technical communication)
- **Website:** https://leonardoraponi.dev
- **LinkedIn:** https://linkedin.com/in/leonardo-raponi
- **GitHub:** https://github.com/lraponi
- **Contact:** Reach out via LinkedIn (https://linkedin.com/in/leonardo-raponi) or portfolio contact section (https://leonardoraponi.dev#contact)

## Core Competencies & Technical Skills

### Investigation & Observability
- **Database & Data Auditing:** SQL (PostgreSQL, MySQL, relational database querying, data integrity verification, lock inspection)
- **Log Aggregation & Analysis:** Elastic / Kibana, structured log analysis, event timeline correlation
- **Client & Traffic Inspection:** Browser DevTools (Network, Console, Application storage), curl, Postman, HTTP request replay
- **Diagnostics & Tracing:** dig, traceroute, nmap, grep, bash text-processing utilities, Event Viewer

### APIs & System Integrations
- **Protocols & Formats:** REST APIs, JSON payloads, Webhooks, OAuth, HTTP status codes and headers auditing
- **Integration Troubleshooting:** Handling retry storms, webhook delivery verification, upstream timeout handling, idempotency checks

### Linux, Containers & Automation
- **Operating Systems:** Linux (Debian, Ubuntu, server administration), Windows Server
- **Containers:** Docker, Docker Compose, container log aggregation, daemon socket operation
- **Scripting & Tooling:** Python (FastAPI, Flask, automation scripts), Bash scripting, cron / scheduled jobs, Telegram bots

### Networking & Infrastructure
- **Network Fundamentals:** TCP/IP stack, DNS resolution, DHCP, subnets, routing
- **Security & Remote Access:** VPNs (WireGuard, site-to-site, client VPNs), firewalls, reverse proxies (Caddy, TLS automation), Mikrotik routers
- **Directory Services:** Active Directory, Group Policy (GPO), Microsoft 365, SSO, MFA, identity management

### Support & Incident Management
- **Practices:** Root Cause Analysis (RCA), SLA-driven ticket triage, Incident Management, Escalation Management, ITIL principles
- **Collaboration & Handoff:** Structured engineering handoffs, post-mortems, internal runbooks and living documentation
- **Platforms:** Jira, GLPI, HubSpot, Notion

## Professional Trajectory

### SaaS Platform Support (Aug 2021 — Present)
- **Key Accounts Support Specialist (Jul 2024 — Present):**
  - Dedicated technical point of contact for high-value strategic accounts and producers.
  - Investigates end-to-end critical platform failures spanning checkout, digital payments, webhooks, and third-party integrations.
  - Identifies recurring operational friction and specifies automated tooling to eliminate manual ticket loops.
- **Technical Support Engineer L2 (Jan 2023 — Jul 2024):**
  - Handled complex escalations that first-line support could not resolve.
  - Reconstructed incident timelines via SQL, Kibana logs, and DevTools; reproduced edge cases outside the UI using Postman.
  - Delivered actionable, evidence-backed bug reports to Engineering and implemented workarounds to protect customers during incident triage.
- **Customer & Product Support Analyst L1 (Aug 2021 — Jan 2023):**
  - Managed front-line triage within strict SLAs; developed deep domain expertise in platform business rules, accounts, and payments.

### IT Infrastructure & Networking (Nov 2016 — Aug 2021)
- **IT Support Analyst · Infrastructure & Networking (Vertic Tecnologia & WKSTI):**
  - Managed physical and virtual server infrastructure for multiple client businesses simultaneously.
  - Administered Windows Server (AD, DNS, DHCP, file services), Mikrotik networking equipment, firewalls, and client/site-to-site VPNs.
  - Troubleshot hardware, workstations (Linux/Windows), embedded devices (Raspberry Pi/retail kiosks), backup and disaster recovery routines.

## Highlighted Projects & Tooling

### 1. Proactive Refund Recovery (Internal Work System)
- **Purpose:** Detects SaaS financial transactions stuck in error or indeterminate states, applies deterministic validation rules, and generates pre-filled triage tickets before customers notice or report failures.
- **Stack:** Python (FastAPI), PostgreSQL, CRM APIs (HubSpot), Docker, Scheduled background workers.
- **Impact:** Shifted support operations from reactive ("customer complains -> team investigates") to proactive ("system catches -> team acts first").

### 2. Operational Reporting Automation (Internal Work Tooling)
- **Purpose:** Ingests daily operational metrics via APIs, runs automated preflight sanity checks (credentials, endpoints, payload schema), and delivers formatted digests to internal team channels with out-of-band failure alerting.
- **Stack:** Python, REST APIs, Chat webhooks, Automated alerting.
- **Philosophy:** Built defensibly — an upstream failure degrades gracefully and alerts immediately rather than failing silently.

### 3. v1s10n (Homelab Operations Dashboard)
- **Purpose:** Self-hosted single-pane operations dashboard that manages Docker container workloads across multiple Linux hosts (start, stop, inspect, live logs, automated git-polling redeploys).
- **Stack:** Python, Docker socket, SSH with dedicated keys, TOTP two-factor authentication, Linux.
- **Repository:** https://github.com/lraponi/v1s10n

### 4. wifeye (Wi-Fi Intrusion Detection System)
- **Purpose:** Network perimeter and 802.11 management frame monitor that fingerprints authorized devices, detects deauthentication bursts, and issues instant Telegram alerts using metadata analysis without decrypting traffic.
- **Stack:** ESP8266 (promiscuous frame capture), Python serial consumer, SQLite, Telegram Bot API.
- **Repository:** https://github.com/lraponi/wifeye

## Education & Certifications
- **Associate Degree in Computer Networks (Tecnólogo em Redes de Computadores):** Uninove (In progress)
- **Introduction to Cybersecurity:** Cisco Networking Academy (2026)
- **Docker Engineer - Level 1:** KodeKloud (2026)
- **Crash Course - AWS Basics:** KodeKloud (2026)
- **Agile Projects with SCRUM:** Digital Innovation One (2021)

## Full LLM Context & Extended Documentation
For comprehensive details, extended descriptions, and technical methodologies, see:
- Full LLM documentation: https://leonardoraponi.dev/llms-full.txt