Software Engineer (Blockchain)

Job Title:

Block-Builder Engineer

Who we are:

Adaptiq is a technology hub specializing in building, scaling, and supporting R&D teams for high-end, fast-growing product companies in a wide range of industries.

About the Product:

An advanced block construction platform operating on the Ethereum mainnet that processes order flow, transaction bundles, and submits finalized blocks through relay networks in real time. It addresses neutral and efficient block building to unlock new decentralized finance capabilities, including intrablock lending and execution extensions. The system handles high-throughput data pipelines and strict latency requirements, backed by comprehensive observability and analytics to drive iterative improvements based on live production metrics. Strong engineers are essential to maintain system health under real-time load, verify data-driven hypotheses, and innovate on core protocol logic.

About the Role:

The Block-Builder Engineer will join an experienced team in Kraków or Warsaw to develop and maintain a next-generation Ethereum block construction system. You will own pipeline components that ingest order flow and transaction bundles, manage relay submission paths, and ensure stable performance under real-time load. Your work will include building and refining observability platforms, conducting controlled A/B experiments, and driving reliability improvements such as panic mitigation and latency regression detection. As you ramp, you will contribute to optimization-driven block building logic, on-chain intrablock lending protocols, and an execution extension, gaining autonomy and deep technical ownership across the core stack.

Key Responsibilities:

• Integrate and process order-flow ingestion, bundle and transaction handling, back-pressure management, and reintegration of data for block inputs.
• Develop and maintain relay submission paths to ensure end-to-end block delivery under production load.
• Build and enhance telemetry and dashboards using Grafana, Prometheus, Loki and SQL to provide trusted observability.
• Diagnose and correct measurement issues—broken counters, misleading dashboards, and erroneous denominators—to maintain metric accuracy.
• Design, execute and analyze controlled A/B experiments in production, reporting findings objectively, including inconclusive results.
• Identify and resolve system panics, dropped messages, and latency regressions, with automated tests to prevent recurrence.
• Optimize data pipelines and processing systems for high-throughput, low-latency performance.
• Contribute to the development of intrablock lending protocols and associated trusted-execution components.
• Collaborate on an execution extension (BEX) and future protocol and exchange-layer enhancements.

Required Competence and Skills:

• 2–4 years of professional software engineering experience shipping and operating production systems.
• Minimum 2 years working on Ethereum or other EVM-compatible blockchains.
• Proficiency in Rust or strong systems experience in Go, C++ or Java with eagerness to adopt Rust.
• Solid understanding of concurrent and real-time code within large, existing codebases.
• Strong SQL skills and practical experience with Python for data analysis and tooling.
• Familiarity with monitoring and analytics tooling and a drive to ensure metric correctness.
• Rigorous engineering habits, including comprehensive testing and clear distinction between verified and assumed behavior.
• Data-driven mindset with a habit of querying logs and databases to validate change impact.

Nice to Have:

• Exposure to Ethereum block-building protocols (PBS/MEV), smart contract interactions, or trading systems.
• Experience with high-throughput data pipelines, time-series databases, or large-scale analytics.
• Familiarity with Ethereum client internals (reth, geth, revm) or deploying services on Kubernetes and Docker.

Why Us:

We provide 20 days of vacation leave per calendar year (plus official national holidays of a country you are based in).

We provide full accounting and legal support in all countries we operate.

We utilize a fully remote work model with a powerful workstation and co-working space in case you need it.

We offer a highly competitive package with yearly performance and compensation reviews.