Senior Android SDK Engineer - Network QoE & Speedtest

Ookla; Madrid; On-site; EUR 70,000 - 110,000; Full time

Job summary

Ookla, a global leader in connectivity intelligence, seeks a Senior Android Engineer to own the Android SDKs for CQoE and Speedtest. You will work across Kotlin/Java and the C++ engine, collaborating with partners and internal teams to deliver robust measurement features on millions of Android devices.

You’ll drive architectural decisions and ensure quality across JNI/NDK boundaries. You will engage in design reviews, implement features, and push AI-assisted tooling with proper guardrails for

Qualifications

• 5+ years of software development experience.
• Experience with Android using Kotlin and Java.
• Substantial experience building and maintaining SDKs or libraries.
• Strong data literacy: SQL for production data, Python for analysis.
• Curious, proactive stance toward AI and modern engineering practices.
• Excellent debugging and data analysis skills.
• Strong time management and self-driven work ethic.

Responsibilities

• Design, implement, and maintain network measurement features in the CQoE and Speedtest Android SDKs for external partners and internal apps.
• Work across the JNI/NDK boundary into the shared C++ measurement engine and debug native code.
• Introduce AI-assisted tooling with safety, privacy, security, and verification guardrails.
• Stay hands-on with architecture discussions and deliver end-to-end on features and fixes.
• Roll out SDK changes with feature flags, quality checks, and post-release verification.

Skills

Android development

Kotlin

Java

SDK design

JNI/NDK

C++

Problem solving

Tools

SQL

Python

Git

Job description

Ookla, a global leader in connectivity intelligence, seeks a Senior Android Engineer to own the Android SDKs for CQoE and Speedtest. You will work across Kotlin/Java and the C++ engine, collaborating with partners and internal teams to deliver robust measurement features on millions of Android devices.

You’ll drive architectural decisions and ensure quality across JNI/NDK boundaries. You will engage in design reviews, implement features, and push AI-assisted tooling with proper guardrails for