Smart Contract Developer

OneAPPS Consulting (www.oneapps.com) is a Technology consulting firm based out of London and offices across Europe. We are working on various projects involving diverse, multicultural teams with clients across the Europe. We are an invaluable partner and our teams have collaborated to support the growth of our clients. With more than 7 locations worldwide we help our clients to deliver their projects smoothly. We look forward to getting to know you and working with you.

We are seeking an experienced Smart Contract Developer to join our Digital Asset Development team. This is a hands on, security focused role responsible for designing, developing, testing, and deploying smart contracts that underpin institutional digital asset capabilities such as tokenisation, smart contract management, wallet management, and integration with blockchain infrastructure (public, permissioned and private EVM / non-EVM networks). You will work closely with cross-functional teams to build robust, scalable, and secure digital asset products that meet our business and technical requirements.

Role Description

• Design and implement robust, efficient, and secure smart contracts for EVM and non-EVM networks, aligning contract behaviour with product and platform requirements.

• Collaborate with product and engineering stakeholders to translate business logic into decentralized logic, ensuring correctness, resilience, and clear operational semantics.

• Develop and maintain smart contracts supporting tokenization and lifecycle operations, including patterns used for institutional needs (e.g., permissioning / whitelisting and proxy / upgrade approaches where required).

• Build comprehensive unit and integration tests, and contribute to quality gates for contract releases. Perform internal security reviews and support external audits, proactively identifying and mitigating common smart contract vulnerabilities (e.g., re-entrancy and front running classes of issues).

• Own and evolve the smart contract toolchain (development environments, linting/static analysis, dynamic analysis, testing and audit readiness), ensuring tools are approved, integrated into the SDLC tollgates, and support consistent coverage and secure-by-design outcomes.

• Build and maintain smart contract CI/CD workflows using existing build processes, integrating the contract repositories and pipeline stages needed to automate build/test/analysis artefacts and support controlled deployments in line with enterprise SDLC governance.

• Contribute to engineering excellence through code reviews, documentation, and maintaining a high standard of security and quality in an iterative delivery environment.

• Coordinate and partner with third party smart contract auditors by preparing audit-ready packages (scope, threat model context, code freeze/tag, and supporting artefacts), facilitating walkthroughs and Q&A, triaging findings with engineering, and driving remediation and re test cycles through to audit sign off and release readiness

Core/Must have skills

• Strong, demonstrable experience developing smart contracts in Solidity or a similar language with a security-first mindset.

• Experience across the smart contract lifecycle: design, build, test, deploy, and maintain.

• Experience with token standards and advanced token models, including partitioned or permissioned token approaches and proxy/upgrade patterns.

• Strong knowledge of secure coding practices for smart contracts and ability to identify/mitigate common vulnerability classes.

• Proficiency with smart contract development and deployment tools (such as Hardhat) and modern testing patterns.

• Understanding of EVM / Ethereum fundamentals (e.g., smart contracts and EVM execution model)

• Web3 integration experience, including using libraries such as Ethers.js / Web3.js to interact with smart contracts, sign/send transactions, and integrate contract functionality into dApps and services.

• Blockchain cryptography fundamentals, including strong understanding of public/private key cryptography, signing/verification concepts, and the role of cryptographic mechanisms (e.g., key management requirements and approved algorithms) in securing blockchain transactions and wallets.

Good to have skills

• Experience building dApps and integrating front ends with smart contracts (e.g., Web3 interaction patterns).

• Familiarity with institutional digital asset platform components such as tokenization, smart contract management, wallet management, and integration patterns that connect on chain activity to off chain services.

• Gas optimization and scalability techniques, including awareness of gas-related patterns/protocols (e.g., Gasless transaction approaches such as OpenGSN).

• Exposure to microservices and back-end integration in modern stacks (e.g., NodeJS/Java/C#) and producing technical documentation for architecture and code.

• Experience developing for non EVM smart contract platforms (e.g., Canton/DAML or other non EVM chains such as Stellar or Solana), including adapting designs to different execution models, tooling, and network fee mechanics

If this role sounds like you, we invite you to apply. Thanks.