Software Engineer in Blockchain — Crypto Custody Platform

Company Description DMG Blockchain Solutions is a vertically integrated blockchain and cryptocurrency company that designs, operates, and manages end-to-end digital solutions across the blockchain ecosystem. The organization focuses on building secure, scalable platforms that enable institutions and enterprises to effectively monetize blockchain technologies. DMG combines technical innovation with practical applications, providing products and services that support digital asset management and infrastructure. Team members collaborate in a dynamic environment that values problem-solving, security, and compliance in the rapidly evolving crypto space. About the role We are building a financial technology platform that enables institutional customers to manage fiat accounts, transactional wallets and digital-asset custody wallets. We are looking for a backend-focused a Software Engineer with Blockchain Exposer who can work across our existing web application while helping us build the next generation of our custody infrastructure. You will work primarily with TypeScript, NestJS, Next.js and PostgreSQL. You will also help us evolve from relying entirely on third-party custody providers toward operating more of our own wallet, transaction-policy, blockchain-monitoring and secure-signing infrastructure. This is not a blockchain research or smart-contract-only role. We need a strong engineer who understands how production blockchain systems work for Digital Currency: wallet addresses, transaction construction, signing, broadcasting, confirmations, reorganizations and reconciliation. You will not be expected to invent a new MPC cryptographic protocol. You will be expected to help us safely integrate audited cryptographic components and build the platform around them. What you’ll work on Build and maintain features across our NestJS API, Next.js portal and supporting services.Design provider-neutral custody workflows that can work with third party wallet infra provider and in near future DMG own internal signing infrastructure.Evolve our transaction system from simple quorum approvals into immutable, policy-controlled transaction intents.Implement approval workflows, authorization receipts, segregation of duties, transaction limits and destination policies.Build custody-space, keyset, wallet-address and key-lifecycle management.Integrate secure MPC, HSM or confidential-computing components without exposing key material to the main application.Build chain-specific transaction construction and broadcasting services.Expand blockchain support across EVM networks and eventually other families such as Bitcoin and Solana.Improve Harbor, our blockchain observation and reconciliation service.Integrate blockchain infrastructure providers such as QuickNode for RPC, streams and historical data.Handle deposits, withdrawals, confirmations, finality, failed transactions, replacements and blockchain reorganizations.Build reliable asynchronous workflows using queues, idempotency and transactional outbox patterns.Design secure administrative and disaster-recovery workflows for custody operations.Write unit, integration and end-to-end tests for sensitive financial workflows.Participate in architecture discussions, code reviews, operational planning and incident investigation.Document important technical and security decisions clearly.Our current technology TypeScriptNestJSNext.js and ReactPostgreSQLDrizzle ORMJest and end-to-end testingDockerRedis and background job processingEthers.js and BitcoinJSFireblocksQuickNodeAWS servicesREST APIs, webhooks and blockchain JSON-RPCYou do not need prior experience with every item, but you should be comfortable learning and working throughout this stack. What we’re looking for Approximately 4 or more years of professional software engineering experience, or equivalent demonstrated impact.Strong TypeScript and Node.js experience.Experience building and operating production web applications and backend APIs.Experience working with relational databases, data modelling, migrations and transactions.Ability to work across backend services, integrations and frontend application code.Experience designing asynchronous and failure-tolerant workflows.Good understanding of authentication, authorization, role-based access and secure API design.Experience writing meaningful automated tests for business-critical workflows.Ability to understand an established codebase, follow its patterns and improve it incrementally.Strong communication skills and the ability to explain technical trade-offs clearly.Blockchain experience You should have practical experience with several of the following: Building or integrating blockchain wallets.EVM transactions, chain IDs, gas, nonces and transaction receipts.ERC-20 token transfers and event logs.Blockchain JSON-RPC APIs.Signing and broadcasting raw transactions.Wallet address derivation and hierarchical deterministic wallets.Transaction confirmations, finality and reorganizations.Blockchain indexing, webhooks or event-stream processing.Deposit and withdrawal lifecycle management.Reconciliation between on-chain activity and an internal ledger.Custodial versus non-custodial wallet models.Hot, warm and cold-wallet security concepts.We are looking for practical engineering knowledge. You do not need to be a cryptographer, but you should understand why private keys and MPC shares must remain outside normal application services and databases. Security and custody knowledge Experience in any of the following is valuable: Any Institutional custody platform.MPC or threshold-signature systems.Distributed key generation and key ceremonies.HSMs, cloud KMS products or confidential-computing environments.Secure key backup, recovery, rotation or resharing.Transaction policy engines and multi-user approval workflows.Cryptographic workload attestation.Financial-system audit trails and segregation of duties.AML/KYT or blockchain risk-screening integrations.Security reviews, penetration testing or incident-response exercises.Direct MPC implementation experience is a strong advantage, but it is not required. We expect to use audited cryptographic implementations rather than create our own protocol from scratch. What success looks like Within your first few months, you will: Understand the architecture and contribute production changes across the existing repository.Become familiar with our wallet, transaction, policy and blockchain-monitoring workflows.Help strengthen the boundary between client approvals, custody signing and blockchain execution.Improve the reliability and test coverage of sensitive transaction workflows.As you grow into the role, you will: Help design and implement our provider-neutral custody architecture.Contribute to per-customer keyset and wallet lifecycle management.Help integrate secure signing infrastructure.Expand supported blockchain networks safely.Improve deposit, withdrawal, confirmation and reconciliation reliability.Help us reduce our dependency on Fireblocks through a controlled, auditable migration.Nice to have Experience with NestJS, Next.js or Drizzle ORM.Experience in fintech, banking, payments, custody or regulated financial systems.Experience with Bitcoin UTXOs or Solana transactions.Experience operating high-value or security-sensitive systems.Familiarity with double-entry ledgers.Experience with queues, outbox patterns and distributed state machines.Experience working with external security auditors or cryptography specialists.Familiarity with infrastructure as code, cloud security and production observability.The kind of engineer who will succeed here You are comfortable moving between product requirements, database design, backend architecture, blockchain infrastructure and frontend workflows. You take security seriously without allowing it to become vague or theoretical. You think carefully about retries, duplicate requests, partial failures, auditability and recovery—not only the successful path. You can identify when something belongs in normal application code and when it requires specialized cryptographic or security expertise. You are comfortable collaborating with external auditors and specialists when necessary. Most importantly, you want to build reliable financial infrastructure where correctness and security matter.