Leondrino Exchange, Inc., a FinTech startup with its roots in Berlin/Germany, is a Delaware corporation with an office in New York that was founded in November 2014. We provide Currency-Management-as-a-service (CMaaS) using cryptocurrency and distributed ledger technology.
Leondrino Exchange will be responsible for the issuance and the administrative process of the Leondrino supply and the compliance with the agreed monetary policy and wants to become the most trusted issuer and administrator of private, virtual currencies for corporations with strong brands.
We offer an international working environment and conditions in a very promising startup as well as efficient introduction and continuous training within a supportive and proactive team.


Your Responsibilities:

  • Being part of a team to develop a middleware to integrate external partners and internal systems including blockchain based components
  • Work with cross-functional project teams to design and develop web-based applications
  • Discuss and evangelize best practices with project teams
  • Developing libraries of APIs to provide a sophisticated touch point to our technology
  • Produce high quality, maintainable and scalable software – follow a use case based and test-driven approach
  • Perform maintenance and enhancements on existing or new projects
  • Work on projects either individually or in collaboration with other developers
  • Ensure architectural principals and standards are maintained across your code and project lifecycles
  • Ensure quality of work through development standards and QA procedure
  • Collaborate and work closely with other technical leads and domain experts, such as Blockchain based Infrastructure, Database, Middleware, and Front End (App/ Web) as the team develops features and platform enhancements (defining, building and troubleshooting applications)
  • Capable of leading and contributing to technical discussions (written and oral)

Required Skills and Knowledge:

  • Bachelor’s Degree and 5+ years professional experience in web application development and at least 2 years of related experience with large-scale and enterprise projects
  • Solid understanding of OOP programming and principles
  • Comprehensive experience with .NET (4.5, 4.6, Core 1.0, 1.1), ASP.NET, C#, and ASP.NET MVC Core 1.0
  • Comprehensive experience with modern front-end development techniques using HTML, CSS and Javascript
  • Knowledge and experience building robust back-end web development solutions
  • Knowledge and experience with major internet protocols and methodologies (APIs, web services, AJAX, etc.
  • Knowledge of Web Experience and understanding of SQL Server (or other RDBMs, e.g. MySQL, Oracle, etc.)
  • Good knowledge of Entity Framework 6.0, Core 1.0
  • Good understanding of Dependency Injection and Localization in .NET Core applications
  • Ability to work in a self-directed manner
  • Ability to communicate effectively
  • A love for technical challenges
  • Ability to learn quickly and thrive in a fast-paced and dynamic environment
  • Ability to work in a distributed, international team environment
  • Excellent problem-solving skills
  • Strong analytical skills
  • Strong experience with Microsoft IIS service and security settings
  • Very good English knowledge (written and oral to communicate via e-mail and within the team). Knowledge of other languages will be considered as a plus

Preferred Skills/Advantages:

  • General web sockets communication knowledge, Pub/Sub and RPC knowledge
  • Service Bus technologies
  • REST Services
  • Entity Framework 6+
  • Unit testing
  • Windows Azure services

Experience with:

  • IIS 7+ Administration
  • Source Control: GIT/GitHub
  • Agile development methodology. Experience with Jira
  • An eye for design


Your Responsibilities:

  • Play a key role during implementation of the infrastructure for Leondrino currencies including architectural responsibilities
  • A passion for developing and solving complex issues in virtual currency environment
  • Actively participate in the improvement of the block chain and supporting infrastructure for Leondrino’s currency implementation
  • Development of modules for integration of internal and third-party components like wallet(s), bank software, POS applications, etc.
  • A hands on mentality is strongly preferred; skills and experience are very valued
  • Work with external companies on security audits

Required Skills and Knowledge:

  • Bachelor degree (i.e. at least 3 years degree) or 2+ years of cryptocurrency  experience with High School degree
  • Background and experience in software development
  • Work experience in Git/GitHub
  • Deep Knowledge in Bitcoin, Ripple, Ethereum, Stellar, BigchainDB or another currency implementation incl.
    • experience to develop a sample blockchain
    • peer to peer protocols knowledge
    • basic knowledge of cryptographic and encoding algorithms
  • Fast learner and fast worker (i.e. time and task management)
  • Able to contribute with ideas to improve current processes
  • Very good languages skills in English (written and oral). Skills in other languages will be considered as a plus


  • Work experience in Node.js and Docker
  • Experience with webservice design, distributed systems, virtualization and cloud technology
  • .NET and C# experience is a plus
Your Responsibilities:

  • To adapt and customize open source crypto currency related components and to contribute to open source projects
  • To participate in the product development in the field of processing and data protection
  • To evaluate and measure quality of cryptography and the probabilities of vulnerability in certain situations

Required Skills and Knowledge:

  • Bachelor degree (i.e. at least 3 years’ degree) or 2+ years of cryptocurrency experience with High School degree
  • Mathematical background
  • Knowledge and certain experience in public cryptography infrastructure (PKI), TLS, SSL
  • Knowledge and certain experience in implementing cryptography algorithms and or crypto currency implementation such as Bitcoin, Ripple, Ethereum, Stellar, BigchainDB or others
  • Knowledge and experience with APIs of open source cryptographic software
  • Fast learner and fast worker (i.e. time and task management)
  • Able to contribute with ideas to improve current processes
  • Very good English language skills (written and oral). Other language skills will be considered as a plus


  • Knowledge of society processes and the requirements for the completion of data/impacts of errors
  • Experience in virtual currency and blockchain infrastructure
Your Responsibilities:

  • Adjust Smart Contracts for Initial Coin Offerings
    • Adjust Ethereum based smart contracts for ICOs
    • Construct new smart contracts
  • Blockchain & Software Development
    • Involved in development, testing, release, support and maintenance activities of internal / external web applications using Node.js, Express, HTML, CSS & jQuery
    • Prepare to take over responsibilities to povide structure to development activities following proper SCRUM / Agile methodologies (with internal and external developers)
  • Ad-hoc Development Projects
    • Execute and develop ad-hoc technical projects to meet management’s needs
    • Recommend system solutions by comparing advantages and disadvantages of different approaches

Required Skills and Knowledge:

  • Bachelor’s degree in computer science or computer engineering.
  • 3+ years of software development experience required.
  • 1+ years of blockchain application development experience.
  • 1+ years of Javascript, Node.js, Linux/Unix OS, MongoDB, Express, HTML, CSS & jQuery, UI/UX experiences. (idelly also with BigChainDB)
  • Previous involvement in ICO’s
  • Expert understanding of Ethereum and the inner workings of the EVM.
  • Ability (and a track record) to ship high quality, well crafted code running on Ethereum.
  • Strong unit testing culture.
  • Extensive experience working with cryptographic protocols (using GPG/PGP is a plus).
  • Experience writing smart contracts and ERC20 Tokens.
  • Deep knowledge in Node.js, Bitcoin, Ethereum


  • Experience contributing or managing open source projects (link to your github profile).
    • Ideal candidate has built and released distributed applications, has worked with the Ethereum and/or Bitcoin blockchain, and has experience with Solidity, Clojure, or Serpent.
    • Bonus if you have built financial services apps.
Your Responsibilities:

  • Development of the user experience for our Leondrino applications (focus on concept, interaction and interfacedesign)
  • Development of UX concepts, user journeys and user interfaces for different end users, taking into account the requirements of our users / customers and the management
  • Development of userflows, wireframes and prototypes to effectively communicate user guidance, interaction and design ideas
  • Planning, implementation and evaluation of usability tests and user research methods
  • Create visuals, how-to videos, and artwork for our Help / FAQ pages and social media campaigns, and design and implement social media games related to our Leondrino applications
  • Close collaboration with product management, development and marketing
  • To communicate concepts and ideas within the team and to stakeholders

Required Skills and Knowledge:

  • Successfully completed university studies (design, media information or a comparable discipline)
  • Professional experience in the design of responsive web applications and mobile apps
  • Deep knowledge and experience with UI / UX Design
  • Profound theoretical and practical knowledge in user-centered design
  • Deep practical knowledge in Responsive Design
  • Profound experience and safe handling of tools such as Adobe Creative Suite and Balsamiq
  • Knowledge of HTML 4/5 and CSS 3
  • You enjoy a cooperative, goal-oriented and interdisciplinary teamwork
  • Incisive qualityconsciousness and love to solve complex problems
  • Very good communication skills and an independent, result-oriented way of working
  • Very good English language skills (written and oral). Other language skills will be considered as a plus


  • Knowledge and experience with mobile platform design guidelines
  • Knowledge in Javascript
  • Ability to provide the design results in suitable HTML and CSS format
  • Experience with an agile product development and a Lean startup environment will be considered as a plus
  • We are also looking for:
    • Innovative power, creativity and knowledge
    • Enthusiasm and self-initiative
    • Enthusiasm for new technologies
    • Solution-oriented thinking
    • Good analytical skills
    • Team spirit and social skills

Start Date: September 2017

Recruitment: initially as freelancer/part time with full time perspective

We are looking for an office assistant starting at the earliest possible date.

Your Responsibilities:

  • general secretarial work and office management
    (telephone, correspondence, mail, travel co-ordination and reservations, travel expense accounting, etc.)
  • support for customer acquisition including preparation of presentation material and event co-ordination
    (CRM care and other back-office activities)

Required Skills and Knowledge:

  • vocational training as a European secretary, office clerk or graduate in language studies is a plus
  • minimum of 2 years work experience (e.g. law firm, accountancy firm) preferred
  • very good language skills in German and English (oral and written) absolutely necessary. Other languages skills will be considered as a plus
  • sound Microsoft Office skills
  • experience with CRM and CMS tools
  • reliable and autonomous working method
  • friendly and confident manner, well-groomed appearance


  • You will work directly for the management team (CEO/COO)
  • Opportunity to gain project management skills
  • initially part time with full time perspective

We offer:

  • An international work environment in an aspiring startup
  • The opportunity to get involved in the core team and to contribute pro-actively with ideas
  • Flexible working hours, because good ideas need space to breathe


If so, we are looking forward to your application. To be part of our adventure, please send us your application (motivation letter, CV and certificates) stating your earliest possible start date and your salary expectations via email to We are very much looking forward to your candidature.
All announcements are regulated to all eligible candidates (f/m) regardless of age, gender, disability, religion, belief, ethnic origin or sexual orientation.