JAVA Software Engineer Expert (Blockchain)

Location:

Remote Work Modality:

100% Remote (Europe & Latin America) About the Opportunity

At

5411 Hub , a headhunting firm specialized in senior and expert-level technology roles across LATAM, the U.S., and Europe, we are partnering with a

leading global company in blockchain infrastructure and decentralized technologies

to recruit a

Software Engineer Expert . This is a

core engineering role , focused on the evolution of a

blockchain client (node/client software)

that supports EVM compatibility, consensus improvements, and secure, high-performance protocol features. The Role (explained clearly)

This is

not

a typical Web3 application or dApp development role. It is a

deep engineering position , centered on: Core blockchain client development EVM compatibility at the protocol level Consensus, execution, and performance improvements Backend, low-level engineering in

Java You will work alongside highly experienced blockchain engineers in a fast-paced, research-driven environment, building

Web3 infrastructure at the foundation level , where architectural and implementation decisions directly impact network security, stability, and scalability. Key Responsibilities

Develop new features for the blockchain client using

Java

as the primary language. Analyze complex technical requirements, which may include: Ethereum consensus changes Bitcoin scripts Internal research papers and protocol proposals Design and implement features following best practices for

security, scalability, and performance . Write clean, modular, well-tested code using solid

object-oriented design principles . Actively participate in peer reviews and technical discussions to continuously improve code quality and development processes. Write

simple Solidity smart contracts

to validate and test client features at the EVM level (testing purposes only, not production dApp development). Share research outcomes and technical insights with distributed, global teams. Maintain and expand

CI/CD automation , including GitHub Actions pipelines. What You Bring (and what it really means)

Strong Technical Background

5+ years of professional experience in

Java , or equivalent experience with JVM-based languages (Kotlin, Scala, Gradle) or

C++ . 3+ years of experience working on

core blockchain components , such as: Node or client development Consensus or execution layers Protocol-level infrastructure Solid understanding of

Ethereum or Bitcoin architecture , including: Smart contract execution models Consensus mechanisms Core protocol design Ability to reason deeply about

security, performance, and edge cases

in complex distributed systems. Strong command of

data structures

(trees, graphs, etc.) and their practical application in system design. Basic experience with

Solidity , with a clear understanding of how to interact with smart contracts (primarily for testing and validation). Familiarity with

CI/CD pipelines

and automation tools such as GitHub Actions. When the role refers to “core blockchain components”, it means

critical infrastructure , not surface-level application development. Professional Profile & Collaboration

Hands-on engineer with strong ownership and accountability. Clear technical communicator and collaborative team player. High standards for code quality, security, and documentation. Comfortable working in a

fully remote, global, and diverse environment . Fluent English

(spoken and written) is required. What’s Offered

Competitive compensation aligned with expert-level seniority. 100% remote work from Europe or Latin America. Access to global coworking spaces. Strong work–life balance, including generous vacation, sick leave, and parental leave policies. Annual learning budget for training, certifications, and language courses. Opportunity to work on

mission-critical blockchain infrastructure with global impact . Monthly allowance for contractors to support connectivity and well-being.