Senior Back-End Engineer, DeFi Wallet
Paris, France
Full time
Office
Compensation is not specified
Role
Backend Engineer
Description
DESCRIPTION
Blockchain.com is the forefront software platform for digital assets globally. We are seeking Kotlin and Solidity Developers with expertise in blockchain protocols and EVM networks. As a backend engineer on the DeFi team, you will be involved in a variety of projects, such as enhancing our non-custodial wallets network support and developing smart contracts. Additionally, you will be tasked with integrating third-party vendors supplying data for crypto tokens, DApps, and DAOs and centralizing logic from wallet clients into backend services.
In the role of a Senior Back-End Engineer, your responsibilities include leading technical discussions, influencing the approach, and advocating for best engineering practices to positively impact the team's development.
RESPONSIBILITIES
- Develop robust, reliable software to manage multiple networks and support our expanding range of products and users
- Collaborate with an engineering team dedicated to maintaining high standards and deploying secure and high-performing systems
- Engage directly with multiple blockchains in the core of Blockchain.com's solution
- Utilize open source technologies like Docker, Kafka, and MySQL
- Prioritize security in all aspects of the work
- Collaborate with interdisciplinary teams to consistently deliver high-quality products
- Optimize existing systems for scalability, extensibility, and performance while creating reusable, modular code for various Blockchain.com products
REQUIREMENTS
- Integrity, the most essential quality for this role
- Proficiency in Typescript, Solidity, and ideally Kotlin/JVM
- Experience with Blockchain technologies, particularly EVM or non-EVM chains and defi protocols
- Strong motivation, self-driven, and enthusiastic about cryptocurrencies
- Comprehensive understanding of blockchain systems and ideally prior experience working closely with one
- Ability to navigate novel challenges and curiosity to learn new technologies
- Advocacy for best engineering practices, proficiency in multiple programming languages, and a practical approach to solving complex problems
- Commitment to high levels of test coverage, technical documentation, and effective monitoring
- Accountability for all assigned projects
COMPENSATION & BENEFITS
- Competitive salary based on experience and equity in a leading company
- Prime office location in Paris with mandatory on-site work for four days per week
- Work from Anywhere policy
- Opportunity to play a significant role and progress in a rapidly expanding technology company within an emerging industry
- Unlimited vacation policy, inclusive of performance-based bonuses paid in cash
- Company-issued Apple equipment
Skills Required
Blockchain.com
Website
www.blockchain.comCompany size
Not specified
Location
United States
Description
Not specified
bitcastle .
KOL Business Development
City Of Manila, Philippines
City Of Manila, Philippines
Full time
Remote
About the Company
Bitcastle is a cryptocurrency exchange platform which aims to create a new age of exchange where everyone can use it safely and have fun. As we expand and take a more active approach to global expansion, bitcastle is looking to hire a Full-Time KOL Business Development to join our team.
About the Role
We are seeking a dynamic and results-driven KOL Business Development to drive user growth and enhance brand visibility for our exchange. In this role, you will be responsible for identifying, engaging, and nurturing relationships with local KOLs, influencers, communities, projects, and strategic partners to promote our platform.
- Identify and build relationships with local KOLs/influencers/, communities, projects, and other potential partners to promote the exchange in order to achieve user growth.
- As a representative of the exchange, to build and maintain a good relationship with KOLs and marketing channels to achieve long-term partnership
- Be responsible for the execution and performance of KOL marketing strategy, track and analyze results, and make adjustments to ensure optimal performance and maximum ROI.
- Stay updated with local industry developments trends, conduct market research and create strategies when required
- Attend events as a representative of the exchange when required, expand network and bring in more leads for the exchange
Requirements:
- Experience as KOL BD in similar companies/markets
- Understanding of cryptocurrency
- Fluent in English
Preferred Qualification:
- Japanese speaking proficiency
Bitcastle is a cryptocurrency exchange platform which aims to create a new age of exchange where everyone can use it safely and have fun. As we expand and take a more active approach to global expansion, bitcastle is looking to hire a Full-Time KOL Business Development to join our team.
About the Role
We are seeking a dynamic and results-driven KOL Business Development to drive user growth and enhance brand visibility for our exchange. In this role, you will be responsible for identifying, engaging, and nurturing relationships with local KOLs, influencers, communities, projects, and strategic partners to promote our platform.
- Identify and build relationships with local KOLs/influencers/, communities, projects, and other potential partners to promote the exchange in order to achieve user growth.
- As a representative of the exchange, to build and maintain a good relationship with KOLs and marketing channels to achieve long-term partnership
- Be responsible for the execution and performance of KOL marketing strategy, track and analyze results, and make adjustments to ensure optimal performance and maximum ROI.
- Stay updated with local industry developments trends, conduct market research and create strategies when required
- Attend events as a representative of the exchange when required, expand network and bring in more leads for the exchange
Requirements:
- Experience as KOL BD in similar companies/markets
- Understanding of cryptocurrency
- Fluent in English
Preferred Qualification:
- Japanese speaking proficiency
bitcastle .
Customer Service Executive
City Of Manila, Philippines
City Of Manila, Philippines
Part time
Remote
About the Company
Bitcastle is a cryptocurrency exchange platform which aims to create a new age of exchange where everyone can use it safely and have fun. As we expand and take a more active approach to global expansion, bitcastle is looking to hire a Part- Time Customer Service Executive to join our team.
About the Role
The role involves managing customer inquiries, handling KYC processes, responding to emails, and monitoring messages across platforms like Telegram and WhatsApp. The ideal candidate will have strong Japanese language skills and a customer service background. This role will be fully remote.
- Handle customer inquiries via email and chat support.
- Support customer service operations, including but not limited to user research, handling enquiries, process withdrawal applications, KYC, bug reporting, Q&A updates.
- Understand policies and procedures of global customer support, adhere to policies set, ensuring high quality support is provided to users in accordance with global standard.
- Create and post customer announcements.
- Monitor and respond to messages on Telegram and WhatsApp.
- Provide support related to Forex and Crypto (knowledge is a plus).
- During business hours, in addition to responding to customer inquiries, you will be asked to perform tasks such as operating systems to create support-related systems or help center articles as needed, checking payment status, and editing or revising FAQ page
- Maintain a high level of professionalism in customer interactions.
- Adapt to potential future responsibilities, including chatbot and phone support.
- Work together and support other departments to report and solve any customer queries.
Requirements:
- Minimum 2 years of experience in customer service.
- Japanese language proficiency (mandatory).
- Ability to work 3 weekdays + 2 weekends (at least 1 weekend day required).
- Strong communication and interpersonal skills.
- Available to start immediately.
- Strong written and verbal communication skills.
- Must have a PC available for work (smartphones and iPads are not acceptable).
- Must have an internet environment with no data usage restrictions.
Preferred Qualification:
- Knowledge of Forex and Crypto.
Bitcastle is a cryptocurrency exchange platform which aims to create a new age of exchange where everyone can use it safely and have fun. As we expand and take a more active approach to global expansion, bitcastle is looking to hire a Part- Time Customer Service Executive to join our team.
About the Role
The role involves managing customer inquiries, handling KYC processes, responding to emails, and monitoring messages across platforms like Telegram and WhatsApp. The ideal candidate will have strong Japanese language skills and a customer service background. This role will be fully remote.
- Handle customer inquiries via email and chat support.
- Support customer service operations, including but not limited to user research, handling enquiries, process withdrawal applications, KYC, bug reporting, Q&A updates.
- Understand policies and procedures of global customer support, adhere to policies set, ensuring high quality support is provided to users in accordance with global standard.
- Create and post customer announcements.
- Monitor and respond to messages on Telegram and WhatsApp.
- Provide support related to Forex and Crypto (knowledge is a plus).
- During business hours, in addition to responding to customer inquiries, you will be asked to perform tasks such as operating systems to create support-related systems or help center articles as needed, checking payment status, and editing or revising FAQ page
- Maintain a high level of professionalism in customer interactions.
- Adapt to potential future responsibilities, including chatbot and phone support.
- Work together and support other departments to report and solve any customer queries.
Requirements:
- Minimum 2 years of experience in customer service.
- Japanese language proficiency (mandatory).
- Ability to work 3 weekdays + 2 weekends (at least 1 weekend day required).
- Strong communication and interpersonal skills.
- Available to start immediately.
- Strong written and verbal communication skills.
- Must have a PC available for work (smartphones and iPads are not acceptable).
- Must have an internet environment with no data usage restrictions.
Preferred Qualification:
- Knowledge of Forex and Crypto.
OpenCover
Backend Blockchain Engineer
London, UK
London, UK
Full time
Hybrid
👋 GM
We are OpenCover — our mission is to keep the world safe onchain.
OpenCover.com operates at the intersection of blockchain security and insurance. Working in tandem with leading underwriters and industry players, we protect individuals, businesses and institutions against onchain risks such as malicious transactions, smart contract exploits and depegs.
Founded by Y Combinator alums, our team is backed by Tier 1 investors including Alliance, Coinbase Ventures (Base Ecosystem Fund), NFX, Village Global and Orange DAO, with support from the Lloyd’s of London Lab.
Want to join a high-performance, high-integrity team taking onchain safety to the next level? Read on.
🚀 Your role
You would join the founding team to develop core backend infrastructure working closely with our CTO. Your role would focus on expanding the first transaction security layer to insure billions in value. The work involves collaborating with top protocols and industry players to prevent incidents like the ByBit hack from ever happening again.
Areas you’ll work on
Soft auditing and semantic modelling of leading protocol designs and functions.
Designing, implementing and backtesting transaction validation checks.
Developing asset pricing and transaction risk models.
Tracking exposure and other insurance metrics in real-time.
Iterating and expanding our API based on customer feedback.
Staying up to date with industry trends including EIPs and security incidents.
You’d be a great fit if
You’re a generalist who quickly embraces new technologies and challenges with a passion for building products from the ground up in a collaborative, tight-knit team.
You go all out to use your knowledge and work well autonomously but know when to reach out for support.
You have 5+ years of full-time experience developing and shipping backend services with Node.js and TypeScript.
You’ve designed, implemented and/or audited smart contracts on EVM-compatible chains and have hands-on experience using DeFi.
You’re familiar with PostgreSQL, messaging brokers, AWS/GCP, Docker, Bash and Linux.
You are constantly improving your tech stack and use AI tools to accelerate development.
🙌 Our offer
Put your dent in the universe: build products for and with some of the largest players across Web3 and TradFi.
Directly impact company trajectory and play a key role in driving onchain adoption.
Work IRL with the team at Lloyd’s of London 1–5 days a week— your choice!
Flexible hours with 28 days of paid holiday plus company closure days.
Competitive compensation based on experience + 0.1–0.5% equity.
The equipment you need to do your best work + $1,000 for well-being and personal development each year.
Company-paid travel to events and conferences, if that’s your thing!
Ready to apply?
Head to opencover.com/apply/bbe and get shortlisted in 10 minutes or less.
We are OpenCover — our mission is to keep the world safe onchain.
OpenCover.com operates at the intersection of blockchain security and insurance. Working in tandem with leading underwriters and industry players, we protect individuals, businesses and institutions against onchain risks such as malicious transactions, smart contract exploits and depegs.
Founded by Y Combinator alums, our team is backed by Tier 1 investors including Alliance, Coinbase Ventures (Base Ecosystem Fund), NFX, Village Global and Orange DAO, with support from the Lloyd’s of London Lab.
Want to join a high-performance, high-integrity team taking onchain safety to the next level? Read on.
🚀 Your role
You would join the founding team to develop core backend infrastructure working closely with our CTO. Your role would focus on expanding the first transaction security layer to insure billions in value. The work involves collaborating with top protocols and industry players to prevent incidents like the ByBit hack from ever happening again.
Areas you’ll work on
Soft auditing and semantic modelling of leading protocol designs and functions.
Designing, implementing and backtesting transaction validation checks.
Developing asset pricing and transaction risk models.
Tracking exposure and other insurance metrics in real-time.
Iterating and expanding our API based on customer feedback.
Staying up to date with industry trends including EIPs and security incidents.
You’d be a great fit if
You’re a generalist who quickly embraces new technologies and challenges with a passion for building products from the ground up in a collaborative, tight-knit team.
You go all out to use your knowledge and work well autonomously but know when to reach out for support.
You have 5+ years of full-time experience developing and shipping backend services with Node.js and TypeScript.
You’ve designed, implemented and/or audited smart contracts on EVM-compatible chains and have hands-on experience using DeFi.
You’re familiar with PostgreSQL, messaging brokers, AWS/GCP, Docker, Bash and Linux.
You are constantly improving your tech stack and use AI tools to accelerate development.
🙌 Our offer
Put your dent in the universe: build products for and with some of the largest players across Web3 and TradFi.
Directly impact company trajectory and play a key role in driving onchain adoption.
Work IRL with the team at Lloyd’s of London 1–5 days a week— your choice!
Flexible hours with 28 days of paid holiday plus company closure days.
Competitive compensation based on experience + 0.1–0.5% equity.
The equipment you need to do your best work + $1,000 for well-being and personal development each year.
Company-paid travel to events and conferences, if that’s your thing!
Ready to apply?
Head to opencover.com/apply/bbe and get shortlisted in 10 minutes or less.
Astra Byte Sync
Web3 Gaming Platform Development Team
Full time
Remote
Company Overview
A fastest growing Blockchain company is looking to create a decentralized gaming platform that empowers players and developers alike. We are currently seeking to build a talented team to bring their vision to life.
Position Overview
We are looking for skilled professionals to join our development team for a Web3 gaming platform. The ideal candidates will be passionate about blockchain technology and gaming, and possess the expertise to contribute to various aspects of our project. We are hiring for the following roles:
1. Frontend Developers
Responsibilities: Design and implement user interfaces for the gaming platform using modern frameworks (e.g., React, Vue.js). Collaborate with UX/UI designers to create engaging and intuitive user experiences.
Qualifications: Proficiency in HTML, CSS, JavaScript, and relevant frameworks. Experience with Web3 technologies is a plus.
2. Backend Developers
Responsibilities: Develop and maintain server-side logic, database management, and API integration. Ensure the platform's performance, security, and scalability.
Qualifications: Strong knowledge of Node.js, databases (e.g., MongoDB, PostgreSQL), and experience with cloud services. Familiarity with blockchain technology is advantageous.
3. Blockchain Developers
Responsibilities: Design and implement smart contracts, manage blockchain integrations, and ensure the security of decentralized applications. Collaborate with the team to optimize blockchain performance.
Qualifications: Expertise in Solidity, JavaScript, Rust, or Python. Experience with Ethereum and other blockchain platforms is essential.
4. Technical Leader
Responsibilities: Oversee the technical direction of the project, mentor team members, and ensure best practices in development. Collaborate with stakeholders to align technical goals with business objectives.
Qualifications: Proven experience in leading development teams, strong problem-solving skills, and a deep understanding of blockchain technologies.
5. Project Manager
Responsibilities: Manage project timelines, resources, and deliverables. Facilitate communication between team members and stakeholders, ensuring that the project stays on track and within budget.
Qualifications: Strong organizational and leadership skills, experience in project management methodologies (Agile, Scrum), and familiarity with the gaming and blockchain industries.
What We Offer
Competitive salaries and benefits
A dynamic and collaborative work environment
Opportunities for professional growth and development
The chance to be part of an innovative project that shapes the future of gaming
How to Apply
If you are passionate about gaming and blockchain technology and are excited to contribute to a groundbreaking project, we would love to hear from you! Please submit your resume and a cover letter detailing your relevant experience and why you would be a great fit for our team.
Join us in creating the next generation of gaming experiences!
A fastest growing Blockchain company is looking to create a decentralized gaming platform that empowers players and developers alike. We are currently seeking to build a talented team to bring their vision to life.
Position Overview
We are looking for skilled professionals to join our development team for a Web3 gaming platform. The ideal candidates will be passionate about blockchain technology and gaming, and possess the expertise to contribute to various aspects of our project. We are hiring for the following roles:
1. Frontend Developers
Responsibilities: Design and implement user interfaces for the gaming platform using modern frameworks (e.g., React, Vue.js). Collaborate with UX/UI designers to create engaging and intuitive user experiences.
Qualifications: Proficiency in HTML, CSS, JavaScript, and relevant frameworks. Experience with Web3 technologies is a plus.
2. Backend Developers
Responsibilities: Develop and maintain server-side logic, database management, and API integration. Ensure the platform's performance, security, and scalability.
Qualifications: Strong knowledge of Node.js, databases (e.g., MongoDB, PostgreSQL), and experience with cloud services. Familiarity with blockchain technology is advantageous.
3. Blockchain Developers
Responsibilities: Design and implement smart contracts, manage blockchain integrations, and ensure the security of decentralized applications. Collaborate with the team to optimize blockchain performance.
Qualifications: Expertise in Solidity, JavaScript, Rust, or Python. Experience with Ethereum and other blockchain platforms is essential.
4. Technical Leader
Responsibilities: Oversee the technical direction of the project, mentor team members, and ensure best practices in development. Collaborate with stakeholders to align technical goals with business objectives.
Qualifications: Proven experience in leading development teams, strong problem-solving skills, and a deep understanding of blockchain technologies.
5. Project Manager
Responsibilities: Manage project timelines, resources, and deliverables. Facilitate communication between team members and stakeholders, ensuring that the project stays on track and within budget.
Qualifications: Strong organizational and leadership skills, experience in project management methodologies (Agile, Scrum), and familiarity with the gaming and blockchain industries.
What We Offer
Competitive salaries and benefits
A dynamic and collaborative work environment
Opportunities for professional growth and development
The chance to be part of an innovative project that shapes the future of gaming
How to Apply
If you are passionate about gaming and blockchain technology and are excited to contribute to a groundbreaking project, we would love to hear from you! Please submit your resume and a cover letter detailing your relevant experience and why you would be a great fit for our team.
Join us in creating the next generation of gaming experiences!
Liza BlockDAG
Blockchain Go Developer
Cape Town, South Africa
Cape Town, South Africa
Full time
Remote
BlockDAG Network is revolutionizing the world of distributed ledger technology through Directed Acyclic Graph (DAG)-based infrastructures. Our goal is to create secure, scalable, and high-throughput decentralized networks. We uphold a culture of innovation, excellence, and continuous collaboration, providing an environment where forward-thinking professionals can thrive.
About the Role:
We are seeking an accomplished Lead Go Developer & DevOps Engineer to take on a strategic, cross-functional leadership position. This unique role sits at the intersection of software development and infrastructure operations. You will not only design and implement cutting-edge, Go-based components for our DAG-powered blockchain but also oversee the cloud infrastructure and automation frameworks that keep our platform resilient, secure, and scalable. As a team leader, you will collaborate closely with product, security, and data teams, championing best practices and ensuring cohesive execution across the engineering organization.
Key Responsibilities:
Technical Leadership & Strategy:
Drive architectural decisions, code quality standards, and performance optimizations across Go-based services.
Serve as the technical lead on initiatives that impact the entire platform stack—both software components and cloud infrastructure.
Advocate for and implement industry best practices, guiding team members and stakeholders to adopt efficient, secure, and scalable approaches.
Cross-Team Collaboration & Coordination:
Interface with product managers, security experts, data teams, and other engineering groups to ensure alignment on priorities, timelines, and deliverables.
Mentor and coach junior and mid-level engineers, fostering a culture of learning, professional development, and continuous improvement.
Communicate complex technical concepts clearly to non-technical team members, ensuring that strategic decisions are well-informed and broadly understood.
Infrastructure & DevOps Ownership:
Architect and maintain robust cloud infrastructure for distributed ledger operations, ensuring high availability, low latency, and optimal resource utilization.
Refine and scale CI/CD pipelines, observability systems, and automation scripts to support rapid feature delivery without compromising reliability or security.
Rapidly diagnose and resolve production incidents, proactively implementing preventative measures and incident response best practices.
Qualifications:
Development Expertise:
7+ years of professional software development experience, with at least 3+ years focused on Go in production environments.
Deep understanding of concurrency, memory management, profiling, and optimization in Go.
Proven track record designing, building, and maintaining large-scale, distributed systems.
Infrastructure & Operations Expertise:
5+ years in SRE, DevOps, or infrastructure roles, with demonstrated success managing complex cloud-native systems (AWS, GCP, or Azure).
Proficiency with container orchestration (Kubernetes), infrastructure-as-code tools (Terraform, Ansible), and modern CI/CD pipelines.
Strong observability skill set, including hands-on experience with monitoring, logging, and alerting frameworks (e.g., Prometheus, Grafana, ELK).
Domain Knowledge & Leadership Skills:
Familiarity with blockchain, DAG-based networks, or advanced distributed system concepts is highly desirable.
Exceptional communication skills, with experience facilitating cross-team collaboration and consensus-building.
A proven leader who can mentor engineers, set clear objectives, and cultivate an environment of transparency, accountability, and continuous improvement.
Preferred:
Exposure to cryptographic primitives, P2P networking, and consensus protocols in decentralized systems.
Hands-on experience with performance testing, capacity planning, and advanced debugging in complex, distributed environments.
Experience driving security best practices and governance across application and infrastructure components.
Benefits:
Competitive compensation and comprehensive benefits.
Influence on groundbreaking blockchain technology and the evolution of decentralized networks.
A supportive, dynamic environment that values leadership, innovation, and professional growth.
About the Role:
We are seeking an accomplished Lead Go Developer & DevOps Engineer to take on a strategic, cross-functional leadership position. This unique role sits at the intersection of software development and infrastructure operations. You will not only design and implement cutting-edge, Go-based components for our DAG-powered blockchain but also oversee the cloud infrastructure and automation frameworks that keep our platform resilient, secure, and scalable. As a team leader, you will collaborate closely with product, security, and data teams, championing best practices and ensuring cohesive execution across the engineering organization.
Key Responsibilities:
Technical Leadership & Strategy:
Drive architectural decisions, code quality standards, and performance optimizations across Go-based services.
Serve as the technical lead on initiatives that impact the entire platform stack—both software components and cloud infrastructure.
Advocate for and implement industry best practices, guiding team members and stakeholders to adopt efficient, secure, and scalable approaches.
Cross-Team Collaboration & Coordination:
Interface with product managers, security experts, data teams, and other engineering groups to ensure alignment on priorities, timelines, and deliverables.
Mentor and coach junior and mid-level engineers, fostering a culture of learning, professional development, and continuous improvement.
Communicate complex technical concepts clearly to non-technical team members, ensuring that strategic decisions are well-informed and broadly understood.
Infrastructure & DevOps Ownership:
Architect and maintain robust cloud infrastructure for distributed ledger operations, ensuring high availability, low latency, and optimal resource utilization.
Refine and scale CI/CD pipelines, observability systems, and automation scripts to support rapid feature delivery without compromising reliability or security.
Rapidly diagnose and resolve production incidents, proactively implementing preventative measures and incident response best practices.
Qualifications:
Development Expertise:
7+ years of professional software development experience, with at least 3+ years focused on Go in production environments.
Deep understanding of concurrency, memory management, profiling, and optimization in Go.
Proven track record designing, building, and maintaining large-scale, distributed systems.
Infrastructure & Operations Expertise:
5+ years in SRE, DevOps, or infrastructure roles, with demonstrated success managing complex cloud-native systems (AWS, GCP, or Azure).
Proficiency with container orchestration (Kubernetes), infrastructure-as-code tools (Terraform, Ansible), and modern CI/CD pipelines.
Strong observability skill set, including hands-on experience with monitoring, logging, and alerting frameworks (e.g., Prometheus, Grafana, ELK).
Domain Knowledge & Leadership Skills:
Familiarity with blockchain, DAG-based networks, or advanced distributed system concepts is highly desirable.
Exceptional communication skills, with experience facilitating cross-team collaboration and consensus-building.
A proven leader who can mentor engineers, set clear objectives, and cultivate an environment of transparency, accountability, and continuous improvement.
Preferred:
Exposure to cryptographic primitives, P2P networking, and consensus protocols in decentralized systems.
Hands-on experience with performance testing, capacity planning, and advanced debugging in complex, distributed environments.
Experience driving security best practices and governance across application and infrastructure components.
Benefits:
Competitive compensation and comprehensive benefits.
Influence on groundbreaking blockchain technology and the evolution of decentralized networks.
A supportive, dynamic environment that values leadership, innovation, and professional growth.
Payment in Crypto