Hào Nguyễn Anh

Software Engineer with 5+ years of experience in VoIP, Contact Center, and Backend Development. Experienced in developing FreeSWITCH, Asterisk, .NET applications, and multi-tenant Contact Center platforms, as well as integrating AI Voicebots, LLMs, CRM, and third-party systems.

VOIP ENGINEER at ODS Join Stock Company (2019-12 – 2023-03)

• Installed, configured, and administered Asterisk and FreePBX systems.
• Deployed PBX systems, including CloudFone PBX, SIM Gateways, and DID platforms for domestic and international telephony.
• Designed and configured IVR call flows using FreePBX and Asterisk dialplans.
• Developed Asterisk dialplans and AGI scripts using Bash and PHP for IVR, outbound calling, last-dial recall, and Zalo OA integration.
• Integrated PBX systems with external platforms via AMI, REST APIs, and Webhooks, including Getfly CRM, 1Office, Bitrix24, Zalo OA, and Google Speech-to-Text.
• Optimized call routing, outbound dialing, and PBX performance.
• Diagnosed and resolved SIP, dialplan, and call routing issues using sngrep, Wireshark, Asterisk CLI, and log analysis.
• Monitored PBX systems using Zabbix (Docker) and Bash automation scripts.

VOIP Implementation engineer at Base Business Solutions (2023-04 – 2025-12)

• Deployed Contact Center solutions across Cloud, Hosted, and On-Premises environments.
• Implemented Cisco Contact Center (CCX/PCCE) infrastructure, including rack installation, Voice Gateway configuration, VMware virtualization, capacity planning, and site readiness.
• Developed and deployed Asterisk outbound auto-dialing solutions using Call Files and AMI for debt collection and customer notification campaigns.
• Deployed IP Telephony (IPT) systems with FreeSWITCH High Availability (HA).
• Operated and maintained Cisco, Asterisk, and FreeSWITCH platforms, including DID connectivity, SIP trunking, and core telephony services.
• Integrated Contact Center platforms with AI Voicebots (FPT AI, Namitech, Biva), CRM systems (HubSpot), Zalo OA, Jira, and Bitrix using REST APIs, Webhooks, and event-driven integrations.
• Developed self-service IVR applications integrated with core banking systems for services such as VIP verification, card activation/deactivation, and credit balance inquiries.
• Built backend logic, reporting, and dashboards using MySQL, Informix, Stored Procedures, and CUIC, while developing core Asterisk dialplans based on business requirements.
• Automated operational workflows using n8n, processing PBX events and delivering real-time notifications.
• Monitored and optimized voice platforms using Grafana, Prometheus, and FreeSWITCH/PJSIP exporters, with automated alerts via Telegram and Webex.
• Diagnosed and resolved complex SIP trunking, voice quality, dialplan, and PBX issues using SIP tracing, Kamailio SBC, and log analysis, collaborating with infrastructure and carrier teams.

AI Contact Center Developer at Base Business Solutions (2026-01 – 2026-06)

• Developed an Asterisk outbound campaign platform with asynchronous AGI processing, using Gemini Live TTS to synthesize dynamic notification messages.
• Developed a multi-tenant SaaS Contact Center platform, supporting deployment across Cloud, Hosted, and On-Premises environments.
• Developed the core FreeSWITCH-based Contact Center platform, including SIP routing, WebRTC, IVR, call processing, XML APIs, telephony integrations, and core modules such as mod_xml_curl, mod_callcenter, and ESL.
• Developed Contact Center applications, including Call Flow Canvas, WebRTC Agent Desktop, Self-Service APIs, rule-based workflow engine, visual flow debugger, QR provisioning, and debt inquiry services.
• Developed backend services and web applications using C#,.NET 8, ASP.NET Core, Entity Framework Core, Dapper, PostgreSQL, Node.js, and REST APIs.
• Contributed to the development and optimization of AI Voicebot capabilities, including LLM integration, Gemini Live, Speech-to-Text (STT), and Text-to-Speech (TTS).
• Leveraged AI coding agents, AI CLI tools, and modern AI development workflows to accelerate code generation, debugging, testing, refactoring, and feature delivery.

Senior Business Analyst – Systems Operations at VPBank - Portfolio Management & Debt Collection Strategy (2026-07 – Present)

• Operated and monitored debt collection platforms, including CRM, Auto Dialer, Callbot, and Contact Center systems, ensuring stable daily operations.
• Developed and executed SQL scripts for campaign preparation, data validation, queue management, parameter updates, and reporting.
• Configured and managed outbound calling campaigns, queue allocation, and system parameters to support debt collection operations.
• Collaborated with business, infrastructure, and vendor teams to troubleshoot incidents, optimize workflows, and improve system performance.

Bachelor's in Telecommunications Engineering – HO CHI MINH CITY UNIVERSITY OF TRANSPORT (2015-09 – 2020-09)