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Alliance for Recruitment, UAB
Senior Full Stack Developer
Alliance for Recruitment, UAB
Alliance for Recruitment, UAB

Senior Full Stack Developer

Alliance for Recruitment, UAB

Job description

About the job

The Senior Full Stack Engineer builds and ships AI product features end to end, from LLM workflows on the backend to intuitive interfaces on the frontend. The role is key to making Sintra's AI helpers reliable, scalable and easy to use. It's a new position in the Engineering department and suits someone who can deliver on their own in a fast-moving team.

Job description

  • Build and maintain AI product features across frontend and backend using TypeScript, Node.js and React.
  • Develop reliable LLM workflows, including tool calling, prompt engineering, error handling and fallback logic.
  • Create user-friendly frontend interfaces for complex AI functionality in collaboration with designers.
  • Implement logging, monitoring and clean architecture to ensure system reliability and scalability.
  • Contribute to code reviews, technical discussions and team collaboration while independently delivering features.

Requirements

3+ years of back-end experience with TypeScript and Node.js (NestJS or Next.js).
Experience in front-end development with React.
Knowledge of SaaS business models.
Experience working in a fast-paced environment.
Proficiency in English.

Nice to have:

Experience with LLM integrations, including tool calling, function definitions and prompt engineering.
Experience implementing payment and subscription systems in web applications.

Company offers

Equity package: a share in the company’s long-term success.
Flexible working model that supports a healthy work–life balance.
Private health insurance.
Workout sessions with a personal trainer.
Free lunch in the office every workday.

€Monthly gross salaryGross/mo  € 5000 - 8000

Location

  • Vilnius, Vilniaus apskritis, Lithuania

Time of work

  • Full-time

Languages

  •  English
  •  Lithuanian
Contact person
Laurynas Lenčiauskas
+37065593361
Sintra AI is a fast-growing tech company building AI helpers for small business owners. Its AI helpers work like teammates: they reply to customers, post on social media, analyze data and more, so people running a business alone finally get help that actually helps. More than 50,000 small business owners use Sintra every day. The company is now growing its Engineering team to make the product even better.

Company website: https://afr.lt/

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