The most interactive ELT / data processing tool you have ever used.

Senior Library Developer

$80k - $100k
Job Type
6+ years
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Sylwia Brodacka
Sylwia Brodacka

About the role

Senior Library Developer

Hi, we are looking for an experienced libraries developer to design and implement high-performance data processing libraries for Enso (enso.org, YC S21), a functional, hybrid visual/textual programming language with immutable memory. You will be working in an incredibly talented team with Jaroslav Tulach (founder of NetBeans, co-creator of GraalVM Truffle) and many more.

What is Enso?

From the business perspective, Enso is a no-code interactive data transformation tool. It lets you load, blend, and analyze your data, and then automate the whole process, simply by connecting visual components together. It can be used for both in-memory data processing, as well as SQL analytics and transformations on modern data stack (ELT). Enso has the potential to disrupt the data analytics industry over the next five years. Currently, the market operates using old-fashioned, limited, and non-extensible software which has been unable to keep up with businesses as they transition to the cloud.

From a technical perspective, Enso is a purely functional, programming language with a double visual and textual syntax representation and a polyglot evaluation model. It means that you can mix other languages with Enso (Java, JavaScript, Python, R) without wrappers and with close-to-zero performance overhead.

Who are we looking for?

Enso would be a great place for you if:

  • You're an experienced libraries developer willing to pick up a new language (Enso).
  • You’re any race, color, religion, gender, national origin, political affiliation, sexual orientation, marital status, disability, age.
  • You like to laugh.
  • You want to work hard, have fun doing it, and own projects from end-to-end.
  • You are friendly and like to collaborate.
  • You move fast and ask for help when needed.
  • You value being part of a team and a community.
  • You can set your ego aside because you know that good ideas can come from anywhere.
  • You enjoy working in public, putting yourself out there and showing your learning.
  • You appreciate a competitive salary.


As a Library Developer you'll be helping to shape, define and build the data analytics and blending APIs provided by Enso. Additionally, you will be help mature the language itself with input on the features needed to build out a new programming language.


We have a few particular skills that we're looking for in this role:

  • Experience in implementing libraries in functional languages (especially those with immutable memory model).
  • Solid understanding of basic algorithms and data structures.
  • Ability to pick up new technologies and languages.
  • Strong problem solving skills but willing to ask for help when needed.
  • Passionate about building well-structured and maintainable code.

It would be a big bonus if you had:

  • Interest in functional languages (Agda, Haskell, Idris, OCaml).
  • Interest in data science.
  • Experience in Java language.
  • Experience in SQL and database technologies.

Avoid the confidence gap. You don't have to match all of the skills above to apply!

Apply here!

Tell us a little bit about yourself and why you think you'd be a good fit for the role!

Why you should join Enso

Enso (https://enso.org) is a no-code interactive ETL and data analysis tool. It lets you load, blend, analyze your data, and then automate the whole process, simply by connecting visual components together. At Enso, we have a world-class team, with developers, community managers, and business developers from all walks of life and backgrounds.

Team Size:10
Location:Kraków, Poland
Sylwia Brodacka
Sylwia Brodacka
Wojciech Danilo
Wojciech Danilo