Backend Engineer · Senior · Transition to Go · Saily

📍 Vilnius, Lithuania
📍 Kaunas, Lithuania

EUR 72,000-86,400 per year

SENIOR

✅ Hybrid

Tech Stack
Tag name is followed by "@" symbol and proficiency level value. About proficiency levels:

1-2 — basic awareness. Minimal hands-on experience, and a rudimentary understanding of the technology's purpose;

3-6 — daily use. Comfortable and regular usage, capable of handling common tasks and challenges related to the technology;

7-9 — you are an expert, you can teach others, you know all the pitfalls and tricks;

10 — exceptional knowledge, comprehensive understanding, and adeptness in all aspects of the technology, including advanced problem-solving. Think twice before claiming or demanding such level.

AI API @ 6 AWS Android CSS Cassandra @ 4 Claude Code Cloudflare Codex Docker Experimentation GraphQL Hilt Jetpack Compose Kafka @ 4 Kotlin Kubernetes @ 1 MySQL @ 4 Next.js NoSQL @ 4 PHP @ 4 PostgreSQL @ 4 Python @ 4 React Redis @ 4 Ruby @ 4 SQL @ 4 Tailwind CSS TypeScript iOS

Details

At Saily, engineers build and maintain products that provide secure mobile data in more than 200 destinations. The company fosters an AI-native Product Engineering culture in which engineers solve customer problems end-to-end, while AI agents support coding and repeatable tasks.

Responsibilities

Enhance the Saily product by developing and maintaining new features.
Create features supporting multi-dimensional personalization, A/B experimentation, and analytics.
Develop and maintain a high-quality codebase.
Continuously improve code quality and performance.
Mentor colleagues on development best practices and provide technical guidance.
Influence the overall vision and long-range goals of the team.
Perform research and development operations when required.
Work as part of a cross-functional team and support effective communication.
Collaborate with engineering, product, and design professionals from other teams.
Attend the office three times per week.

Requirements

More than 5 years of backend development experience.
Experience with Python, PHP, or Ruby.
Strong system design knowledge, including understanding which patterns to use and why.
Experience with SQL databases such as MySQL and PostgreSQL.
Experience with NoSQL solutions such as Cassandra and Redis.
Experience with Kafka.
Passion for building easy-to-use, clearly designed APIs.
A collaborative mindset and willingness to discuss, rethink, and redesign ideas.
Experience with Kubernetes and microservice architecture is a plus.

Tools and Technologies

Backend: Go, MySQL, Kafka, Docker, Kubernetes, AWS, Redis
Frontend: Next.js, React.js, TypeScript, GraphQL, Tailwind CSS, Cloudflare Workers
iOS: SwiftUI, Xcode, Combine, SPM, MVVM Architecture
Android: Kotlin, Android Studio, Hilt, Coroutines, Jetpack Compose, MVVM Architecture
AI tools: Claude Code, OpenAI Codex, OpenCode, Cursor with Composer

Benefits

Online and in-person training programs, access to Coursera and Skillshare, mentorship, and internal career opportunities.
Extra vacation days, additional sick leave, special occasion leave, and parenting-related time off.
Premium private health insurance in Lithuania and Poland.
Subscriptions to Calm, Headspace, and Mindletic, plus resilience and mindfulness training and mental health events.
In-house gyms, Multisport and Urban Sport cards, online workouts, group mobility sessions, fitness guidance, and consultations.
Company workations abroad.
The option to work from anywhere when needed.
Gifts for birthdays, work anniversaries, weddings, and new family members.
Summer camps for children and flexible working arrangements for parents.
Team-building activities and company events.
Access to the Vilnius headquarters, including silent rooms, gyms, a game room, a music room, and a coffee bar.