Staff Senior Java Engineer Jobs

Staff/Senior Java Engineer, OKX Wallet (Web3) Who We Are OKX Wallet is OKX's self-custody wallet, built for users worldwide to securely and conveniently store, manage, and use their on-chain assets. The wallet backend operates in a multi-chain, multi-asset, high-concurrency environment shaped by on-chain state uncertainty and strict fund-security requirements — combining the complex-systems challenges of traditional internet backends with the transaction, signing, and on-chain interaction problems unique to blockchain. We're looking for a Senior Java Engineer with roughly 5–10 years of backend experience: someone with strong engineering fundamentals who can independently own core modules, exercise sound judgment on complex problems, and proactively coordinate across upstream and downstream teams to drive work to completion. What You'll Do Own core wallet backend modules. Build and continuously improve address management, asset synchronization, transaction construction, broadcasting, on-chain confirmation, gas estimation, nonce management, and transaction-state tracking. Understand each module's role in the full wallet flow, and keep stability, performance, and maintainability front of mind. For complex requirements, break the problem down before choosing an implementation rather than stacking code or reusing old designs. Build transaction and on-chain interaction scenarios. Work on transfers, token approvals, contract interactions, cross-chain, swaps, DApp connections, and signature-request handling. Understand a transaction's full lifecycle — from initiation through construction, signing, broadcasting, on-chain confirmation, and final state update — and diagnose issues like stuck transactions, duplicate submissions, state inconsistencies, and on-chain success that isn't reflected in the business system, using logs, on-chain data, and call traces. Support multi-chain and new-chain integration. We already support EVM, Tron, and Solana, and continuously onboard new pu

Who We Are At OKX, we believe that the future will be reshaped by crypto, and ultimately contribute to every individual's freedom. OKX is a leading crypto exchange, and the developer of OKX Wallet, giving millions access to crypto trading and decentralized crypto applications (dApps). OKX is also a trusted brand by hundreds of large institutions seeking access to crypto markets. We are safe and reliable, backed by our Proof of Reserves. Across our multiple offices globally, we are united by our core principles: We Before Me , Do the Right Thing , and Get Things Done . These shared values drive our culture, shape our processes, and foster a friendly, rewarding, and diverse environment for every OK-er. OKX is part of OKG, a group that brings the value of Blockchain to users around the world, through our leading products OKX, OKX Wallet, OKLink and more. About the Opportunity Liquidity Platform provides cutting-edge technology that covers all aspects of crypto trading. We build low-latency connectivity to global crypto venues, including both Cefi and Defi venues, strategy services for automated pricing and trading bots, high-frequency data capturing and analysis, and state-of-art micro frontend for trading management. On top of all these infrastructures, we build highly customized strategies to facilitate crypto liquidities. If you are a strong technologist who is excited about the potentials of crypto trading, interested in fully-automated algo bots, we should talk. We are looking for a Java Software Engineer for Liquidity Platform Structured Product Engineering Team. During your tenure with us, you will be working closely with a liquidity manager for strategy development using an in-house build strategy toolkit. You will demonstrate and develop professional capabilities in the following areas: managing inventory & risk of applications, strategic thinking and problem solving, collaborating with product managers, engineers and liquidity managers

OKX will be prioritising applicants who have a current right to work in Singapore, and do not require OKX's sponsorship of a visa Who We Are At OKX, we believe that the future will be reshaped by crypto, and ultimately contribute to every individual's freedom. OKX is a leading crypto exchange, and the developer of OKX Wallet, giving millions access to crypto trading and decentralized crypto applications (dApps). OKX is also a trusted brand by hundreds of large institutions seeking access to crypto markets. We are safe and reliable, backed by our Proof of Reserves. Across our multiple offices globally, we are united by our core principles: We Before Me , Do the Right Thing , and Get Things Done . These shared values drive our culture, shape our processes, and foster a friendly, rewarding, and diverse environment for every OK-er. OKX is part of OKG, a group that brings the value of Blockchain to users around the world, through our leading products OKX, OKX Wallet, OKLink and more. About the Team The Exchange Middle Platform team develops the core modules of the exchange, including the matching engine, real-time market data streaming, and market data analysis. It is the backbone of our industry-leading trading product, used by millions of users. We are seeking highly motivated Java/C++ Engineers to join our cutting-edge team. In this role, you will design, develop, and optimize our systems, which are critical components of our technology stack. We leverage AI technologies to enhance efficiency and performance, offering a unique opportunity for individuals who are eager to learn and grow in a fast-paced, innovative environment. Candidates with prior experience in large internet companies will excel in this role, as they will bring valuable insights into building and maintaining high-performance, distributed systems. What You’ll Be Doing Design and implement innovative solutions for our full range of trading products including spot, future, perp

Location(s): US (remote), Boston (hybrid), or New York (hybrid) Who We Are Toast is driven by building the restaurant platform that helps restaurants adapt, take control, and get back to what they do best: building the businesses they love. We are looking for a Staff Software Engineer to join the Voice AI Team. On the Voice AI Team, our mission is to build and operate the voice platform that powers Toast and to ship novel applications on top of it that create real value across Toast's customer base. This is a greenfield space where the platform and its use cases are being defined together, and the work you do here will be foundational to how Toast uses voice AI for years to come. As a Software Engineer on this team, you'll take ownership of significant projects end-to-end: designing systems, driving execution across the team, and making the technical decisions that shape how the platform grows. You'll work closely with product, engineering, and stakeholders across Toast to turn ambiguous problems into reliable, scalable systems. About this roll* (Responsibilities) Design, build, deploy, and maintain highly resilient and scalable backend services, applications, and core platform components supporting Toast's Voice AI platform used across teams Conceive and lead complex, cross-cutting projects from design through production, owning outcomes and driving alignment across stakeholders and across a broad range of stakeholders Shape the technical direction on your team and beyond by making architectural decisions, defining patterns, and reducing complexity for the engineers and teams that depend on your work Build and evolve integrations with AI platforms and internal Toast systems, making pragmatic tradeoffs between speed, reliability, and long-term scalability Establish and implement patterns for observability, monitoring, and evaluation frameworks for AI-powered systems, using production data to understand and continuously improve system behavior Set a

OKX will be prioritising applicants who have a current right to work in Hong Kong, and do not require OKX's sponsorship of a visa. Please note that Hong Kong is a group-level service hub, and OKX does not carry on a business of operating a virtual asset trading platform in Hong Kong. Who We Are At OKX, we believe that the future will be reshaped by crypto, and ultimately contribute to every individual's freedom. OKX is a leading crypto exchange, and the developer of OKX Wallet, giving millions access to crypto trading and decentralized crypto applications (dApps). OKX is also a trusted brand by hundreds of large institutions seeking access to crypto markets. We are safe and reliable, backed by our Proof of Reserves. Across our multiple offices globally, we are united by our core principles: We Before Me , Do the Right Thing , and Get Things Done . These shared values drive our culture, shape our processes, and foster a friendly, rewarding, and diverse environment for every OK-er. OKX is part of OKG, a group that brings the value of Blockchain to users around the world, through our leading products OKX, OKX Wallet, OKLink and more. About The Opportunity We are looking for a Senior Staff Mobile Engineer to join our P2P & Fiat team, where you will own the mobile engineering for OKX’s peer-to-peer trading and fiat payment experiences across multiple markets. This is a high-ownership role sitting at the intersection of mobile engineering and cross-border payments—you will work closely with compliance, legal, and regional business teams to build localised, regulation-aware payment flows for users across Southeast Asia, LATAM, MENA, and beyond. You bring deep familiarity with P2P trading mechanics, cross-regional fiat payment integrations, and the compliance considerations that govern them. You are also fluent in AI-assisted development and bring the discipline to build, maintain, and continuously improve your own AI engineering workfl

OKX will be prioritising applicants who have a current right to work in Hong Kong, and do not require OKX's sponsorship of a visa. Who We Are At OKX, we believe that the future will be reshaped by crypto, and ultimately contribute to every individual's freedom. OKX is a leading crypto exchange, and the developer of OKX Wallet, giving millions access to crypto trading and decentralized crypto applications (dApps). OKX is also a trusted brand by hundreds of large institutions seeking access to crypto markets. We are safe and reliable, backed by our Proof of Reserves. Across our multiple offices globally, we are united by our core principles: We Before Me , Do the Right Thing , and Get Things Done . These shared values drive our culture, shape our processes, and foster a friendly, rewarding, and diverse environment for every OK-er. OKX is part of OKG, a group that brings the value of Blockchain to users around the world, through our leading products OKX, OKX Wallet, OKLink and more. About The Opportunity We are looking for a Senior Staff Mobile Engineer to join our OEX Mobile Growth team — a pure mobile team sitting at the intersection of engineering rigour, consumer growth craft, and product instinct. This is not a feature delivery role. You will own the client-side architecture for new user acquisition, referral and virality mechanics, and the reward and conversion funnels that drive growth for millions of users. You bring deep expertise in mobile attribution — from MMP design and evolution through to anti-fraud, channel revenue sharing, and ROI evaluation — and you know how to turn attribution data into decisions. You are also fluent in AI-assisted development and bring the discipline to build, maintain, and continuously improve your own AI engineering workflows. What You'll Be Doing Own the client-side architecture for core growth conversion flows — new user acquisition, referral and virality loops, reward mechanics, and act

About Appier Appier is an AI-native Agentic AI as a Service (AaaS) company that uses artificial intelligence (AI) to power business decision-making. Founded in 2012 with a vision of democratizing AI, Appier’s mission is turning AI into ROI by making software intelligent. Appier now has 17 offices across APAC, Europe and U.S., and is listed on the Tokyo Stock Exchange (Ticker number: 4180). Visit www.appier.com for more information. The Impact You’ll Make at Appier We’re looking for a Staff/Senior Machine Learning Platform Engineer to join our Machine Learning Platform Team, which powers end-to-end infrastructure for model training, evaluation, deployment, and monitoring at scale. Our platform supports daily execution of hundreds of ML models and processes billions of data records across batch and streaming pipelines. In this role, you’ll shape the architecture and core components of our ML platform—covering batch (Spark), streaming (Flink), job orchestration (Argo on Kubernetes), and infrastructure tools—while ensuring the platform remains robust, scalable, and developer-friendly. You’ll also champion best practices and modern development tools including LLM-based programming assistants. What You’ll Work On Architect, implement, and scale batch (Spark) and streaming (Flink) pipelines that process billions of records daily for ML training and evaluation. Design and operate robust ML job execution frameworks for training, inference, and post-processing. Build and maintain internal API servers and developer tools to orchestrate ML jobs on Kubernetes (via Argo Workflows, Helm, Terraform). Design and monitor data infrastructure using ClickHouse and PostgreSQL. Ensure high availability and observability through monitoring tools like Prometheus and Grafana. Collaborate with data scientists, product managers, and engineers to deliver reliable and efficient ML platform capabilities. Actively adopt and promote the use of LLM-based tools (e.g.,

Secure Every Identity, from AI to Human Identity is the key to unlocking the potential of AI. Okta secures AI by building the trusted, neutral infrastructure that enables organizations to safely embrace this new era. This work requires a relentless drive to solve complex challenges with real-world stakes. We are looking for builders and owners who operate with speed and urgency and execute with excellence. This is an opportunity to do career-defining work. We're all in on this mission. If you are too, let's talk. Access Management Engineering Team The Okta Access Management Team builds the foundation for authentication and authorization across Okta-protected resources. Our mission is to enable customers to access these resources securely. We develop Okta cloud services and client software that allow users to seamlessly login to devices and use Okta authenticators to access applications securely. Learn more about Okta’s Engineering on our blog . About You We seek a passionate Java Senior Software Engineer to join our dynamic team. The ideal candidate should possess: Solid experience in Java web development. Enthusiasm for developing high-quality, secure, and performant applications. A keen interest in learning about cutting-edge security and identity management challenges. A collaborative mindset and excellent communication skills to work effectively with cross-functional teams. This role offers an exciting opportunity to join a team building innovative identity and security products from the ground up. You will have the chance to work on challenging problems, contribute to the product roadmap, and continuously expand your skills in a rapidly evolving industry. Job Duties and Responsibilities: Collaborate with cross-functional teams (QA, Product, Support, UX) for seamless integration. Following best practices, contribute to technical designs, proposals, and architectural decisions. Develop high-quality, maintainable software components with comprehensive unit/functio

Secure Every Identity, from AI to Human Identity is the key to unlocking the potential of AI. Okta secures AI by building the trusted, neutral infrastructure that enables organizations to safely embrace this new era. This work requires a relentless drive to solve complex challenges with real-world stakes. We are looking for builders and owners who operate with speed and urgency and execute with excellence. This is an opportunity to do career-defining work. We're all in on this mission. If you are too, let's talk. Access Management Engineering Team The Okta Access Management Team builds the foundation for authentication and authorization across Okta-protected resources. Our mission is to enable customers to access these resources securely. We develop Okta cloud services and client software that allow users to seamlessly login to devices and use Okta authenticators to access applications securely. Learn more about Okta’s Engineering on our blog . About You We seek a passionate Java Senior Software Engineer to join our dynamic team. The ideal candidate should possess: Solid experience in Java web development. Enthusiasm for developing high-quality, secure, and performant applications. A keen interest in learning about cutting-edge security and identity management challenges. A collaborative mindset and excellent communication skills to work effectively with cross-functional teams. This role offers an exciting opportunity to join a team building innovative identity and security products from the ground up. You will have the chance to work on challenging problems, contribute to the product roadmap, and continuously expand your skills in a rapidly evolving industry. Job Duties and Responsibilities: Collaborate with cross-functional teams (QA, Product, Support, UX) for seamless integration. Following best practices, contribute to technical designs, proposals, and architectural decisions. Develop high-quality, maintainable software components with comprehensive unit/functio

This is Adyen Adyen provides payments, data, and financial products in a single solution for customers like Meta, Uber, H&M, and Microsoft - making us the financial technology platform of choice. At Adyen, everything we do is engineered for ambition. For our teams, we create an environment with opportunities for our people to succeed, backed by the culture and support to ensure they are enabled to truly own their careers. We are motivated individuals who tackle unique technical challenges at scale and solve them as a team. Together, we deliver innovative and ethical solutions that help businesses achieve their ambitions faster. Staff Java Engineer - Merchant Fraud Prevention As a Staff Software Engineer in the Merchant Fraud Prevention group, you will serve as the core architect and strategic engineering partner for our fraud detection and mitigation ecosystems. You will define the long-term technical vision across 2–3 engineering teams, ensuring our Platforms can detect and prevent evolving fraud vectors at scale. Beyond technical leadership, you will be a key force multiplier, acting as a strategic advisor to engineering leadership, bridging the gap between business strategy and execution, and actively mentoring and growing our senior Individual Contributors (ICs). What you'll do Technical Strategic & Architecture: Own the multi-year technical north star vision for the group, together with the technical leads of each team in the group. Design and evolve high-throughput, low-latency distributed systems capable of processing real-time merchant transactions, integrating complex machine learning models, and handling massive big data pipelines. Leadership Partnership: Partner closely with the Director of Engineering to assess organizational health, surface systemic engineering bottlenecks, and align long-term technical investments with Merchant protection goals. Product Strategy: Shape the strategic roadmap alongside the Director of Engineer

Strength in Trust OneTrust’s mission is to enable innovation through the responsible use of data and AI. We believe that ensuring data is trusted shouldn’t slow teams down—it should accelerate what’s possible. This led us to develop the first technology platform for responsible data use in 2016. Today, with AI representing the latest and most impactful expansion of data yet, OneTrust is once again redefining what responsible innovation looks like. OneTrust, the AI‑Ready Governance Platform™, unifies regulatory intelligence, automation, and connected governance workflows so businesses can continue to move at the speed of AI while ensuring good governance to prevent data misuse at scale. Trusted by thousands of organizations worldwide, OneTrust is shaping the future where trusted data becomes a transformative force for business and society. Strength in Trust OneTrust’s mission is to enable innovation through the responsible use of data and AI. We believe that ensuring data is trusted shouldn’t slow teams down—it should accelerate what’s possible. This led us to develop the first technology platform for responsible data use in 2016. Today, with AI representing the latest and most impactful expansion of data yet, OneTrust is once again redefining what responsible innovation looks like. OneTrust, the AI‑Ready Governance Platform™, unifies regulatory intelligence, automation, and connected governance workflows so businesses can continue to move at the speed of AI while ensuring good governance to prevent data misuse at scale. Trusted by thousands of organizations worldwide, OneTrust is shaping the future where trusted data becomes a transformative force for business and society. The Challenge As a Senior Staff Software Engineer on the AI Governance Engineering team, you will play a critical role in shaping and building OneTrust's next-generation AI Governance platform. You will help transform complex AI governance, compliance, safety, and agent r

Strength in Trust OneTrust’s mission is to enable innovation through the responsible use of data and AI. We believe that ensuring data is trusted shouldn’t slow teams down—it should accelerate what’s possible. This led us to develop the first technology platform for responsible data use in 2016. Today, with AI representing the latest and most impactful expansion of data yet, OneTrust is once again redefining what responsible innovation looks like. OneTrust, the AI‑Ready Governance Platform™, unifies regulatory intelligence, automation, and connected governance workflows so businesses can continue to move at the speed of AI while ensuring good governance to prevent data misuse at scale. Trusted by thousands of organizations worldwide, OneTrust is shaping the future where trusted data becomes a transformative force for business and society. The Challenge As a Senior Staff Software Engineer on the AI Governance Engineering team, you will play a critical role in shaping and building OneTrust's next-generation AI Governance platform. You will help transform complex AI governance, compliance, safety, and agent runtime governance requirements into scalable platform capabilities that enable organizations to confidently build, deploy, and operate AI systems. As a senior technical leader, you will influence architecture, engineering direction, and execution across multiple teams, helping translate product vision into durable, high-quality solutions with meaningful customer impact. Your Mission Serve as a deep technical expert across the AI Governance platform, capable of contributing to and troubleshooting any major component of the system. Drive technical strategy, architecture decisions, and platform evolution based on a strong understanding of AI Governance, distributed systems, and enterprise-scale software. Partner with Product, Architecture, and Engineering leaders to translate long-term vision into actionable technical roadmaps. Lead the design and deliver

Ready to do the most impactful work of your career? At Coinbase , we are uncompromising on our mission to increase economic freedom. The bar is high, the environment is intense, and we like it that way. This isn't a place for complacency, it’s a place to be pushed past your perceived limits. If you're ready to build the future of finance alongside people who refuse to settle for "good enough," you belong here. Coinbase is a remote-first, but not remote-only company. Expect to get together quarterly for intense in-person working sessions called “surges.” learn more about working at Coinbase . Coinbase is building the future of institutional trading as part of the Institutional Everything Exchange, powering the systems that let the world's largest financial institutions trade across markets with speed, depth, and trust. As a Senior Staff Software Engineer on the Exchange team, you'll set the architectural direction for the matching engine, order management, market data, and unified trading systems that clear billions of dollars in daily volume. You'll operate as the most senior technical voice across multiple teams, making the calls on latency, correctness, and resilience that everything else depends on. It's a rare chance to shape a trading platform from the ground up, with the ownership of a startup and the reach of Coinbase. What you'll do: Own the technical strategy and architecture for a core Exchange domain, driving multi-quarter initiatives from ambiguity through incremental milestones to delivery. Lead the design of ultra-low-latency, event-sourced trading systems spanning matching, risk, and market data across cloud and colocated environments. Drive cross-team technical alignment across Exchange, Prime, and Derivatives, securing commitment from senior engineering and product leadership. Set and inspect the quality bar across teams - deterministic testing, failover design, incident leadership, and operational standards for 24/7 markets. Maintain si

At Ripple, we’re building a world where value moves like information does today. It’s big, it’s bold, and we’re already doing it. Through our crypto solutions for financial institutions, businesses, governments and developers, we are improving the global financial system and creating greater economic fairness and opportunity for more people, in more places around the world. And we get to do the best work of our career and grow our skills surrounded by colleagues who have our backs. If you’re ready to see your impact and unlock incredible career growth opportunities, join us, and build real world value. THE WORK: Ripple is building the Internet of Value: infrastructure that moves money as fast as information moves today. Every payment that flows across our network passes through real-time financial crimes controls: sanctions screening, wallet risk analysis, transaction monitoring, and travel rule compliance. The Financial Crimes Engineering team builds and operates that layer. This is the engineering that determines whether payments clear or hold, whether Ripple meets its regulatory obligations across jurisdictions, and whether the network can scale without compromising on compliance. The problem space is genuinely hard: high-throughput distributed systems, real-time decisioning, multi-source coordination across external compliance data providers, regulator-grade audit trails, and resilience. As a Senior Staff Software Engineer on this team, you will set the multi-year technical direction for the compliance control plane and drive its adoption beyond your own team. You will own the architecture of the vendor-agnostic, resilient, provable system that lets Ripple move value without moving financial crime, and you will shape how compliance engineering works across the company. This is a role for someone who defines which problems the organization solves, not only how they get solved: you will set the technical strategy other teams build against, establish the patt

Join Truecaller – The place where innovation meets impact! Truecaller's mission is to build trust in communication by making it safer, smarter, and more efficient. Born in Sweden, trusted by the world, and here’s why we stand out: We are trusted by over 500 million active users every month across 190+ countries We identify over 15 billion calls daily, helping users avoid spam and scams We are powered by a team of 400+ employees from 45+ nationalities We always look for people who take initiative, own their work, and keep raising the bar. An entrepreneurial mindset matters here, especially when it turns bold ideas into real actions. We stay collaborative and focused, always searching for smarter paths forward. If you want to make an impact and grow with a team that inspires millions, you’ll fit right in. The role: As a Senior Staff Software Engineer, Backend, you will lead multi-team initiatives, leveraging your deep technical expertise to ensure alignment, quality, and long-term maintainability across the organization. You will balance hands-on technical guidance with strategic leadership, establishing engineering best practices that transcend your immediate team. By mentoring experienced engineers and building strong relationships with cross-functional stakeholders, you will drive project delivery and ensure our backend infrastructure remains scalable and robust enough to support millions of users worldwide What you will do Lead the team to ensure we build our product efficiently and effectively. Influence product priorities and scope, offering valuable input in decision-making. Communicate complex decisions clearly, weighing the pros and cons of different solutions. Mentor and guide experienced engineers, helping them develop both technically and culturally. Leverage your experience to establish best practices across the engineering team and beyond. Drive project delivery by aligning with cross-functional stakeholders and ensuring the team has everything ne