# Leonardo Raponi — Application Support Engineer (Full Context Dossier) > Comprehensive technical profile, background, architectural mechanisms, and investigative methodologies of Leonardo Raponi. Formatted for direct consumption by Large Language Models, autonomous recruiting agents, and technical evaluators. --- ## 1. Professional Identity & Positioning - **Full Name:** Leonardo Raponi - **Target Roles:** Application Support Engineer, Technical Support Engineer (L2/L3), Systems Support Engineer - **Professional Experience:** ~10 years in IT (5 years on-premise infrastructure & networking + 5 years SaaS platform technical support) - **Geographic Location:** Sorocaba, São Paulo, Brazil (Timezone: America/Sao_Paulo, UTC-3) - **Work Model:** Remote worldwide (experienced in asynchronous collaboration, hybrid and distributed team setups) - **Languages:** - Portuguese: Native - English: Professional Working Proficiency (B2) — Strong written, architectural, and asynchronous technical communication; spoken English actively maintained and functional. - **Canonical Website:** https://leonardoraponi.dev - **LinkedIn Profile:** https://linkedin.com/in/leonardo-raponi - **GitHub Profile:** https://github.com/lraponi - **Contact:** Reach out via LinkedIn (https://linkedin.com/in/leonardo-raponi) or portfolio contact section (https://leonardoraponi.dev#contact) --- ## 2. Core Technical Philosophy: The 4 Operational Pillars ### Pillar 01: The Boundary is Where the Problem Lives The most elusive production failures rarely stay confined within a single application layer. They manifest at the transitions: the application points to the network, the network points to the database, or the payment gateway blames the client payload. Having spent five years in bare-metal infrastructure followed by five years in SaaS platform support, Leonardo operates seamlessly across both sides of this boundary, tracing failures across networks, reverse proxies, application runtimes, and databases. ### Pillar 02: Guesses Are Cheap, Evidence Is Not Discipline in troubleshooting means rejecting early assumptions or superficial explanations: 1. Inspect the raw state in SQL to see what the database recorded. 2. Correlate timestamps across aggregated logs (Elastic / Kibana) to build an irrefutable incident timeline. 3. Use browser DevTools to inspect actual HTTP headers, request bodies, and response codes. 4. Reproduce the failure outside the user interface using authenticated REST API calls in Postman or curl. If a behavior cannot be isolated and reproduced with verifiable evidence, it is not considered solved. ### Pillar 03: The Same Incident Three Times is an Architectural Signal Closing individual tickets resolves immediate symptoms. However, when the same failure pattern recurs a third time, it ceases to be an isolated incident and becomes an operational defect in the system. Leonardo's approach is to halt manual firefighting and design deterministic tooling or automated monitors that catch, classify, and mitigate the issue before users encounter it. ### Pillar 04: The Incident Ends When the Next Person Understands A thorough diagnostic investigation is wasted if it remains trapped in the investigator's head. Leonardo writes clear, structured Root Cause Analyses (RCAs), internal runbooks, and detailed escalation tickets for Product and Engineering. The handoff includes reproducible curl commands, specific database records, relevant log excerpts, and recommended workarounds. --- ## 3. The 7-Hop Diagnostic Workflow (Incident Traceroute) When auditing a reported platform anomaly, the diagnostic path follows this structured order: 1. **Hop 1: Client Layer** — Capture and validate the reported symptom, user context, and initial payload. 2. **Hop 2: Edge & DNS Layer** — Verify DNS resolution, SSL/TLS certificate validity, and edge CDN routing rules. 3. **Hop 3: Browser DevTools Layer** — Inspect request headers, cookies, payload structure, status codes, and browser console warnings. 4. **Hop 4: Application Log Layer** — Trace correlation IDs and reconstruct timeline sequences in Elastic/Kibana. 5. **Hop 5: Database / SQL Layer** — Verify persisted database state, index contention, deadlocks, and table consistency. 6. **Hop 6: Isolated Reproduction Layer** — Replay the exact HTTP transaction via Postman/curl using clean authentication outside the UI. 7. **Hop 7: Root Cause Layer** — Isolate the exact failing component, formulate permanent remediation, and author living documentation. --- ## 4. Technical Skills & Capability Matrix ### Investigation & Observability - SQL: Complex relational queries, schema auditing, transactions, index and lock checks (PostgreSQL, MySQL). - Log Analysis: Elastic / Kibana, structured log parsing, filtering by trace IDs, syslog, systemd journals. - HTTP & API Inspection: Browser DevTools (Network tab, WebSocket inspection, storage), Postman, cURL. - Network Diagnostics: dig, nslookup, traceroute, ping, nmap, netstat, tcpdump, Wireshark packet capture. - System Diagnostics: Event Viewer (Windows Server), grep, awk, sed, top/htop, free, journalctl. ### APIs & Web Technologies - Protocols & Standards: REST APIs, JSON, Webhooks, HTTP/1.1 and HTTP/2, TLS/SSL, OAuth2, JWT. - Integration Troubleshooting: Webhook signature verification, payload serialization, retry storm prevention, rate-limiting response handling (HTTP 429). ### Linux, Virtualization & Containers - Linux Server Administration: Debian, Ubuntu, user permissions, systemd services, SSH key hardening, cron. - Containers: Docker, Docker Compose, Docker daemon socket architecture, multi-container orchestration. - Virtualization: VMware vSphere / ESXi, Hyper-V, virtual switch configuration, snapshot management. - Scripting: Python (FastAPI, Flask, requests, automation scripts), Bash scripting, Telegram Bot API. ### Networking & Identity - Network Protocols: TCP/IP, DNS, DHCP, NAT, VLANs, static and dynamic routing. - Security & VPNs: WireGuard, IPSec, OpenVPN, firewall rule authoring, Mikrotik RouterOS. - Identity & Access: Active Directory, Group Policy Objects (GPO), Microsoft 365, SSO, MFA, digital certificates. ### Support Platforms & Frameworks - Tools: Jira, GLPI, HubSpot CRM, Notion, Confluence. - Methodologies: ITIL, Agile / Scrum (Certified), SLA-driven operational cadence. --- ## 5. Work Experience ### Eduzz (SaaS Digital Products & Checkout Platform) *Period: August 2021 — Present | Location: Sorocaba, SP, Brazil (Hybrid / Remote)* #### Key Accounts Support Specialist (Black) | July 2024 — Present - Serves as the primary technical point of contact for high-value strategic accounts and digital producers. - Leads end-to-end critical incident investigations across platform checkout, payment processing, webhooks, and partner integrations. - Balances high-stakes client relationships with deep technical rigor, providing accounts with transparent, actionable incident reports. - Designs and deploys internal tools and Python automations that eliminate manual triage loops. - Facilitates team agile ceremonies to keep engineering and operational stakeholders aligned. #### Technical Support Engineer L2 | January 2023 — July 2024 - Owned complex escalations that first-line support was unable to diagnose. - Conducted exhaustive investigations using SQL queries, Kibana log queries, DevTools inspection, and Postman API replays. - Formulated temporary workarounds to safeguard client continuity while Engineering prepared permanent hotfixes. - Acted as a technical reference within the support organization, creating pattern guides and standard operating procedures. #### Customer & Product Support Analyst L1 | August 2021 — January 2023 - Resolved high volumes of tier-1 support requests within stringent SLA targets. - Mastered the platform's core business logic, permissions, financial flow, and account management rules. --- ### Vertic Tecnologia Ltda. (IT Managed Services Provider) *Period: January 2020 — August 2021 | Location: Sorocaba, SP, Brazil (On-site & Remote)* - **Role: IT Support Analyst · Infrastructure & Networking** - Maintained production infrastructure across multiple simultaneous corporate client environments. - Administered Windows Server deployments (Active Directory, DNS, DHCP, File Services). - Configured and troubleshot client/site-to-site VPN tunnels, Mikrotik routing equipment, and firewall security policies. - Managed Microsoft 365 migrations, endpoint security solutions, and disaster recovery backup jobs. --- ### WKSTI (IT Solutions & Support Provider) *Period: November 2016 — January 2020 | Location: Sorocaba, SP, Brazil (On-site & Remote)* - **Role: IT Support Analyst · Infrastructure & Networking** - Provided hands-on on-site and remote technical support across diverse hardware, network, and software environments. - Installed, repaired, and hardened Windows and Linux workstations and servers. - Troubleshot networking gear (switches, access points, routers), digital certificates (e-CPF/e-CNPJ), and retail point-of-sale Linux devices. --- ## 6. Projects & Systems Architecture ### Work Project 1: Proactive Refund Recovery System - **Context:** Internal system created to solve transactions stuck in indeterminate states across payment gateway retries. - **Mechanism:** Periodically scans transactional databases, classifies edge cases using deterministic rules, and creates pre-filled triage tickets in the CRM before customers or support agents notice issues. - **Architecture:** `Scheduled Worker --> Detect Stuck Records --> Classify via Deterministic Rules --> Pre-fill CRM Ticket --> Team Acts BEFORE Customer Reports` - **Stack:** Python (FastAPI), PostgreSQL, HubSpot CRM API, Docker. ### Work Project 2: Operational Reporting Automation - **Context:** Automated daily metrics digest with defensive safeguards against silent upstream failures. - **Mechanism:** Pulls operational KPIs via REST APIs, runs preflight verification (tokens, database reachability), formats digests for team channels, and triggers out-of-band alerts if upstream data is unavailable. - **Stack:** Python, REST APIs, Chat Webhooks, Scheduled cron jobs. ### Homelab Project 1: v1s10n (Multi-Host Docker Operations Panel) - **Context:** Self-hosted web interface to observe and control Docker container workloads across separate physical Linux servers without manual SSH sessions. - **Mechanism:** Interacts directly with the local Docker socket for host A, and connects via secured SSH key execution for host B. Monitors git branches to trigger automated stack redeploys. Requires password + TOTP 2FA. - **Repository:** https://github.com/lraponi/v1s10n - **Stack:** Python, Docker Socket, SSH, TOTP, Linux. ### Homelab Project 2: wifeye (802.11 Wi-Fi Intrusion Detection System) - **Context:** Packet-level perimeter monitoring for home/lab wireless environments. - **Mechanism:** ESP8266 microcontroller operates in promiscuous mode to capture 802.11 management frames and stream them over USB serial. A host daemon enriches frame data (OUI vendor lookup, ARP IP resolution, mDNS hostname), detects deauth bursts, and sends Telegram notifications. Traffic is analyzed by metadata only without decrypting payload content. - **Repository:** https://github.com/lraponi/wifeye - **Stack:** ESP8266 C++, Python, SQLite, Telegram Bot API, Linux. --- ## 7. Education & Certifications - **Academic Degree:** Associate Degree in Computer Networks (Tecnólogo em Redes de Computadores) — Uninove (In progress) - **Cisco Networking Academy:** Introduction to Cybersecurity (2026) - **KodeKloud:** Docker Engineer - Level 1 (Credential: 745b3f3d-10dc-4a60-8b73-46b4787b9cb2, 2026) - **KodeKloud:** Crash Course - AWS Basics (Credential: ce43d2b8-3385-4429-a8fe-57c57f622741, 2026) - **Digital Innovation One:** Agile Projects with SCRUM (2021) - **LinkedIn Skill Assessment:** Cybersecurity (Passed badge) --- ## 8. Verification & Contact - **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) - **LLM Compact Index:** https://leonardoraponi.dev/llms.txt - **LLM Full Context:** https://leonardoraponi.dev/llms-full.txt