Senior Mobile SDK Engineer

MWDN; Warszawa; On-site; PLN 180,000 - 300,000; Full time

Benefits offered by this job

29 days PTO

10 paid recovery days

Free English classes

HR support

Flexible working hours

Legal & financial support for independ

Ind contractor support

Job summary

MWDN is seeking a senior Unity SDK engineer to lead architecture and implementation for a mobile gaming SDK. You will own end-to-end development, including in-game components, app-to-app handoff, and cross-platform bridging to iOS and Android.

The role demands deep Unity knowledge and strong English communication. You will work on a high-impact project with a fast-growing gaming platform, offering flexible hours, and a supportive, people-first culture.

Qualifications

• 5+ years engineering experience with Unity/C# shipped to iOS and Android.
• Built or core-contributed to a library or SDK used by other developers, with API design input.
• Deep knowledge of the Unity mobile build pipeline.
• Comfortable with Kotlin/Java and Swift/Obj-C to bridge platforms.
• Good profiling discipline and strong written English.

Responsibilities

• Design and build the SDK: in-game placement components, app-to-app handoff, deep linking, and the referral identifier that survives the store visit and install.
• Build the native layer: iOS and Android bridges, IL2CPP, Gradle and Xcode plugin plumbing, coexistence with other SDKs in the build.
• Hold size, cold-start and frame-time budgets, enforced in CI.
• Own versioning, UPM/Asset Store distribution, Unity LTS support, and migration paths.
• Build the test surface: sample game, cross-version build verification, integration tests, debug mode, and the docs.

Skills

Unity/C# experience

SDK development

Unity build pipeline

Kotlin/Java

Swift/Obj-C

Profiling

Strong English

Tools

Unity

Job description

MWDN is a global IT outstaffing company with 23+ years of experience that connects exceptional tech talent with leading companies across Israel, the USA, Great Britain, and Western Europe. We offer opportunities to work on international products in a stable and professional environment.

Why does MWDN rock?:

Here’s what you can expect when you join MWDN:

• Security: We carefully vet our clients to minimize risks and ensure reliability and timely payments - no fraud or unpleasant surprises.
• Career support: If a project isn’t the right fit, we support you and actively help find new opportunities that match your skills and career goals.
• Legal assistance: We provide guidance on legal matters, including opening and managing your independent contractor or sole proprietorship status, taxes, and related processes.
• Professional development: We offer English courses and professional growth opportunities, as well as team-building events.

Why choose us? MWDN is ranked among the top 5 IT employers in our region according to DOU. We take pride in our transparency and strong commitment to our team. Curious to learn more? See what our employees say about working with us on DOU.

What is your new project?:

Domain: Gaming

Location: US/Israel

Company size: 11-50 employees

Founded in: 2025

What makes this project exciting?:

Our client is building a groundbreaking loyalty platform for mobile gamers, and we're seeking passionate individuals to form the foundation of the engineering team. Product mission is to empower gamers with a new way to discover games, connect with their friends, and earn fantastic rewards.

Joining us, you will get to build the highest quality consumer app in one of the hottest domains in the gaming industry, and make real measurable business impact.

With tens of thousands of daily active users and over a hundred games on clients platform, there are growing fast. Join us and let's open a whole new market together.

You’ll be the first dedicated engineer on the SDK, owning architecture, public API, releases and the partner experience end to end.

What makes you a great fit:

• 5+ years engineering, substantial Unity/C# shipped to iOS and Android.
• You’ve built or core-contributed to a library or SDK other developers consume, with opinions on API design and backward compatibility.
• Deep knowledge of the Unity mobile build pipeline.
• Comfortable below C# in Kotlin/Java and Swift/Obj-C to build bridges and debug platform behaviour.
• Profiling discipline, and strong written English.

Nice to have

• A monetization SDK — offerwall, rewarded video, mediation — or attribution and deep-linking at an MMP.
• Mobile game development or live-ops
• Reward-fraud work.

Your day-to-day in this position:

• Design and build the SDK: in-game placement components, app-to-app handoff, deep linking, and the referral identifier that survives the store visit and install.
• Build the native layer: iOS and Android bridges, IL2CPP, Gradle and Xcode plugin plumbing, coexistence with the other SDKs in the build.
• Hold size, cold-start and frame-time budgets, enforced in CI.
• Own versioning, UPM/Asset Store distribution, Unity LTS support, and migration paths.
• Build the test surface: sample game, cross-version build verification, integration tests, debug mode, and the docs.

Why work with us?

• People-first management with minimal bureaucracy
• A friendly company culture, proven by employees who choose to return
• Flexible working hours
• 29 days of PTO (18 working days per year pluse all national holidays)
• 10 paid recovery days
• Full financial and legal support for independent contractors
• Free English classes, with native speakers or Ukrainian teachers
• Dedicated HR support