Technical Support Engineer (L2)

Contract: Permanent (Full-time)
Location: Bucharest/Paris (Hybrid)
Department: Customer Care – Technical Support
Languages: English (Mandatory), French (Strong Plus)
Seniority: Junior to Experienced
Range: 9800 to 14000 RON/NET monthly

🚀 About Onoff

Onoff is a unique mobile application that allows users to instantly add multiple phone numbers to their smartphones.

We are scaling our B2B solution, Onoff Business and expanding our Technical Support (L2) team to strengthen technical investigations, improve incident resolution and ensure seamless collaboration between Customer Care and Engineering.

🎯 Your Mission

As a Technical Support Engineer (L2), your mission is to investigate and resolve technical issues escalated by Customer Care (L1), identify potential root causes and ensure complex incidents are properly documented and escalated when necessary.

You'll work closely with the Technical Support Team Lead, Engineering, Product and external telecom partners to troubleshoot issues across mobile applications, VoIP, APIs, databases and business integrations.

We're looking for someone with a structured troubleshooting mindset, strong ownership and a genuine curiosity to understand how things work.

🔧 What You'll Do

Technical Investigations: Troubleshoot issues involving voice calls, SMS, mobile applications, Web App, subscriptions and third-party integrations. Reproduce problems, analyze technical evidence and identify possible causes.

API & Database Troubleshooting: Investigate HTTP requests, API responses, JSON payloads, authentication issues and webhooks. Use SQL queries to retrieve and validate information.

Log Analysis: Analyze application logs, error messages and system events to understand failures, correlate information and reconstruct incident timelines.

Expert Escalations: Handle issues escalated by L1, collect relevant technical evidence and prepare structured Jira tickets for Engineering when deeper investigation or code changes are required.

Incident Management & Communication: Participate in investigating production incidents, assess customer impact and collaborate with relevant teams to support resolution. Provide clear, timely technical updates to Customer Care and internal stakeholders, helping ensure consistent and accurate customer-facing communication.

Status Page Monitoring: Monitor internal and public service status pages, validate reported service disruptions against available technical evidence and help maintain accurate incident status information in coordination with the responsible teams.

Post-Incident Reviews & Prevention: Contribute to post-mortem reviews and Root Cause Analysis (RCA) by documenting incident timelines, technical findings, customer impact and resolution steps. Help identify corrective and preventive actions to reduce incident recurrence.

Process Improvement & Continuous Improvement: Maintain a continuous improvement mindset by proactively identifying recurring issues, operational bottlenecks and opportunities for automation. Contribute to troubleshooting guides, runbooks and knowledge-base articles; and help improve workflows while reducing unnecessary escalations between L1, L2 and Engineering.

Cross-Team Collaboration: Work with Engineering, Product, DevOps and Carrier Relations to investigate technical problems and improve service reliability.

🧠 What We're Looking For

Experience: Previous experience in Technical Support, Application Support, QA, SaaS or a similar technical role is an advantage. We welcome candidates at different experience levels who demonstrate strong technical reasoning.

API Knowledge: Understanding of HTTP/HTTPS, REST APIs, JSON, common status codes and basic request/response troubleshooting.

SQL Fundamentals: Ability to retrieve and investigate data using SQL queries, including filtering, joins and basic aggregations.

Log Analysis: Familiarity with reading technical logs, identifying errors and correlating events across different systems.

Networking Basics: Understanding of TCP/IP, UDP, DNS and client-server communication.

Troubleshooting Mindset: Ability to investigate technical issues systematically, identify missing information, test hypotheses and document findings.

Communication & Ownership: Clear communication, attention to detail, willingness to collaborate and responsibility for following issues through to resolution.

⭐ Nice to Have

• Experience with VoIP, SIP, RTP, WebRTC or telecom systems.

• Familiarity with browser Developer Tools, Postman, Jira, Axiom, Kibana or Sentry.

• Experience investigating third-party integrations such as HubSpot, Zoho or other CRM platforms.

• Exposure to cloud services, AWS, webhooks and asynchronous processing.

• Basic scripting or automation knowledge.

• French language skills.

🌱 What We Value

We don't expect every candidate to know all the technologies from day one.

For less experienced candidates, we value curiosity, analytical thinking and willingness to learn.

For experienced candidates, we expect greater technical independence, deeper investigations and the ability to own complex issues end-to-end.

Above all, we value people who don't simply forward problems, but actively investigate, communicate clearly and work toward meaningful resolutions.