Backend Engineer Senior Go Product & Startup Experience Saily

At Saily, we're removing the hassle of staying connected while traveling 6 no roaming fees, no plastic SIM cards, just lightning-fast, secure mobile data in 200+ destinations. Millions of paying customers trust us, and hundreds of thousands of travelers browse Saily at any given moment. We're not looking for someone to close tickets. We're looking for a builder 6 someone who has shipped products real people use, felt the pain of a 2 AM incident on something _they_ care about, and gets a kick out of seeing a metric move because of something they built.

Main Responsibilities

• Own product features end-to-end: from shaping the idea with Product and Design to shipping, measuring, and iterating
• Build features supporting multi-dimensional personalization, A/B experimentation, and analytics
• Make technical decisions with a product lens 6 you'll know the "why" behind every "what"
• Develop and maintain a high-quality, high-performance codebase in Go
• Mentor colleagues and raise the bar on engineering best practices
• Influence your team's vision and long-range goals 6 your opinion on _what_ we build matters as much as _how_
• Run R&D spikes when the path forward isn't obvious
• Collaborate across engineering, product, and design in a cross-functional team

• 5+ years of backend development experience, with strong skills in Python, PHP, Ruby, or similar 6 and readiness to work in Go daily
• Product company experience, ideally startup or scale-up 6 you've worked where speed, ambiguity, and ownership are the norm, not the exception
• B2C experience strongly preferred 6 you understand what it means to build for millions of users you'll never meet, where small UX details and performance directly hit revenue and retention
• Solid system design skills: you know which patterns to use, when, and why
• Experience with SQL (MySQL, PostgreSQL) and NoSQL (Redis, Cassandra) solutions
• Experience with Kafka or similar event-driven systems
• Passion for building APIs that are easy to use and simple to understand
• A collaborative mindset 6 you love discussing, rethinking, and redesigning ideas toward shared success

Nice to have

• You've built your own product 6 a side project, a startup (successful or not), an indie app, anything you took from zero to real users. We find that people who've carried a product themselves think differently: they obsess over the user, they ship, they own outcomes. If that's you, tell us about it 6 it matters more to us than logos on your CV
• Experience with K8s and microservice architecture
• A track record of experiments shipped, hypotheses tested, and impact measured (not just features delivered)
• Comfort working AI-native: Claude Code, Codex, Cursor 6 you see AI as a multiplier, not a threat

• Growth is built into how we work. Extensive online and in-person training programs, access to platforms like Coursera and Skillshare, a mentorship program, and internal career moves when youre ready for something new 6 your development has no ceiling here.
• Rest isnt a reward 6 its part of the deal. Enjoy extra vacation days that grow with your time here, plus additional days off for sick leave, special occasions, and parenting.
• We provide premium private health insurance so you have peace of mind and fast access to care whenever you need it. Available in Lithuania and Poland.
• We provide free subscriptions to top-rated Calm and Headspace apps, offer resilience and mindfulness trainings, and run dedicated mental health events.
• We offer in-house gyms, Multisport and Urban Sport cards, and online workouts. Need something tailored? Our Physical Well-Being experts are here with group mobility sessions, fitness guidance, and one-on-one consultations.
• The entire company flies out abroad. The days are packed with workshops, activities, concerts, and real time together.
• When you need a reset, switch location and work from wherever keeps you sharp, creative, and in the zone.
• Birthdays, work anniversaries, weddings, new family members 6 each is marked with a special gift.
• We organize summer camps for the little ones and offer flexibility that lets you show up both for your family and your team.
• Get ready for team buildings that bring people closer, year-round company events that are equal parts educational and energizing, and the highlights everyone waits for 6 our iconic summer and winter celebrations.
• Whether Vilnius-based or visiting from remote, our Vilnius HQ is fully yours to enjoy. Need focus? Silent room. Need energy? Open gyms. Need a break? Game room, music room, coffee bar. Its a modern workspace built with your comfort in mind.