
B2B • Software Engineering
Callstack is a leading software engineering consultancy that specializes in app development and technological transformation using React and React Native. They provide end-to-end product development services including mobile and web app development, app performance optimization, and tech stack upgrades. Their expertise in the React ecosystem makes them a trusted partner for companies looking to enhance and innovate their software solutions. Callstack also focuses on educating and upskilling development teams, enabling organizations to stay competitive and efficient.
51 - 200 employees
Founded 2016
🤝 B2B
November 12
🗣️🇵🇱 Polish Required

B2B • Software Engineering
Callstack is a leading software engineering consultancy that specializes in app development and technological transformation using React and React Native. They provide end-to-end product development services including mobile and web app development, app performance optimization, and tech stack upgrades. Their expertise in the React ecosystem makes them a trusted partner for companies looking to enhance and innovate their software solutions. Callstack also focuses on educating and upskilling development teams, enabling organizations to stay competitive and efficient.
51 - 200 employees
Founded 2016
🤝 B2B
• Translate product vision into actionable, high-quality user stories for development teams. • Write clear, comprehensive user stories with detailed acceptance criteria, user journeys, and relevant design and architectural specifications. • Define and uphold a strict Definition of Ready (DoR) and Definition of Done (DoD) to ensure clarity and the highest quality throughout the development lifecycle. • Prepare and lead engaging Sprint Demos for stakeholders, showcasing the team's achievements and gathering valuable feedback. • Act as the final gatekeeper for sprint deliverables, signing off on user stories and bugs to confirm they meet all acceptance criteria. • Embrace a data-driven approach by defining success metrics (KPIs, ROI) and aligning with stakeholders on product impact goals. • Lead requirements gathering workshops (Inspect Phase) with technical experts and stakeholders to elicit business needs and mitigate gaps. • Conduct backlog refinement sessions, breaking down epics into manageable, well-defined stories and mapping all dependencies. • Collaborate closely with the Scrum Master and development team during PI Planning and throughout sprints to manage priorities, resolve blockers, and ensure a high story completion rate. • Champion a customer-focused mindset, deeply understanding user pain points and ensuring they are addressed in the product backlog.
• Proven professional experience as a Product Owner, ideally in a software development or corporate environment. • Exceptional communication skills, with the ability to work effectively with cross-functional teams and stakeholders. • Deep understanding of Agile principles and frameworks (SAFe), with hands-on experience in backlog management, refinement, and sprint planning. • A strong analytical and data-driven mindset, with experience in defining and tracking product KPIs. • A genuine passion for understanding customer needs and translating them into functional product requirements. • Demonstrated ability to write clear, concise, and testable user stories and acceptance criteria. • Proactive, curious, and adaptable, with a continuous learning attitude in a fast-paced setting. • Experience with agile management tools such as Jira. • Strong command of business English language (C1), both written and verbal. • Ability to communicate in Polish language (B2/C1). • Independence and proactiveness in daily work. • Nice to have: Professional Scrum Product Owner (PSPO) or Certified Scrum Product Owner (CSPO) certification. • Experience working directly with end-users and conducting user research. • A background in business analysis or a related field.
• 24 paid days off & 30 days paid sick leave for B2B contractors • Fully-covered life insurance • Private healthcare for you and your family • Free access to mental health platform - Helping Hand • Multisport Card or monthly allowance for other sports activities • Individual Wellbeing & Development Budget • Monthly lunch allowance • Flexible working hours and the possibility of remote work • Accounting costs refund for B2B contractors • Cool office in Wrocław city center • Magnificent team events and activities • Company-wide workation and team building workshops • Top-notch hardware - Apple devices • Possibility to participate in React Universe Conf
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