
Mariusz Zak developed cross-chain interoperability features and robust testing infrastructure for the cosmos/solidity-ibc-eureka and anoma/anoma-ci-test repositories. He engineered modular Tendermint light client packages, implemented Solidity-compatible signature handling, and delivered an interchain fungible token standard with end-to-end tests spanning Cosmos, EVM, and Solana. Using Rust, Go, and Solidity, Mariusz refactored codebases for maintainability, introduced deterministic test timing, and enhanced security through improved account validation and access management. His work addressed protocol correctness, reduced CI flakiness, and enabled reliable cross-chain verification, demonstrating depth in distributed systems, smart contract development, and event-driven architecture across multiple blockchain ecosystems.
February 2026: Progress across cosmos/solidity-ibc-eureka delivering cross-chain verification, security hardening, minting enhancements, and stability improvements. Focus on business value: robust cross-chain operations between Solana and Cosmos, safer IBC core, and reliable minting flows; increased test coverage and resilience.
February 2026: Progress across cosmos/solidity-ibc-eureka delivering cross-chain verification, security hardening, minting enhancements, and stability improvements. Focus on business value: robust cross-chain operations between Solana and Cosmos, safer IBC core, and reliable minting flows; increased test coverage and resilience.
January 2026 for cosmos/solidity-ibc-eureka focused on cross-chain interoperability, security, and test automation. Key features delivered include the Interchain Fungible Token (IFT) Standard with cross-chain testing, and Solana interchain security enhancements. A critical encoding bug in anchor-go NewCleanupIncompleteUploadInstruction was fixed to stabilize program IDs and ensure correct instruction discriminators. Together, these efforts improve reliability, security, and testing coverage across Cosmos-EVM and Solana integrations.
January 2026 for cosmos/solidity-ibc-eureka focused on cross-chain interoperability, security, and test automation. Key features delivered include the Interchain Fungible Token (IFT) Standard with cross-chain testing, and Solana interchain security enhancements. A critical encoding bug in anchor-go NewCleanupIncompleteUploadInstruction was fixed to stabilize program IDs and ensure correct instruction discriminators. Together, these efforts improve reliability, security, and testing coverage across Cosmos-EVM and Solana integrations.
December 2025 monthly summary for cosmos/ibc-go focused on interoperability with Ethereum-based clients. Implemented Solidity compatibility for signatures and ABI encoding in attestations, addressing cross-chain verification gaps and enabling seamless integration with Solidity contracts.
December 2025 monthly summary for cosmos/ibc-go focused on interoperability with Ethereum-based clients. Implemented Solidity compatibility for signatures and ABI encoding in attestations, addressing cross-chain verification gaps and enabling seamless integration with Solidity contracts.
Month 2025-10 focused on strengthening interchain test reliability and codebase hygiene for the cosmos/solidity-ibc-eureka repository. Key features and bugs addressed delivered measurable business value and technical improvements.
Month 2025-10 focused on strengthening interchain test reliability and codebase hygiene for the cosmos/solidity-ibc-eureka repository. Key features and bugs addressed delivered measurable business value and technical improvements.
September 2025 monthly summary for cosmos/solidity-ibc-eureka focused on reliability improvements to CI/test infrastructure. Implemented a deterministic test timing mechanism by deriving the test timestamp from trusted_consensus_state plus one hour instead of SystemTime::now(), significantly reducing flaky failures and increasing confidence in test results. This change aligns test timing with consensus semantics, improving CI stability and fostering faster feedback loops for releases.
September 2025 monthly summary for cosmos/solidity-ibc-eureka focused on reliability improvements to CI/test infrastructure. Implemented a deterministic test timing mechanism by deriving the test timestamp from trusted_consensus_state plus one hour instead of SystemTime::now(), significantly reducing flaky failures and increasing confidence in test results. This change aligns test timing with consensus semantics, improving CI stability and fostering faster feedback loops for releases.
August 2025: Delivered a fixture-based testing framework for tendermint-light-client updates and membership verification in cosmos/solidity-ibc-eureka. Enhancements include robust fixture generation and integration into the end-to-end test suite to validate light client operations within the IBC ecosystem. No explicit major bug fixes documented for this period; the focus was on building testing infrastructure to reduce regression risk and improve release confidence.
August 2025: Delivered a fixture-based testing framework for tendermint-light-client updates and membership verification in cosmos/solidity-ibc-eureka. Enhancements include robust fixture generation and integration into the end-to-end test suite to validate light client operations within the IBC ecosystem. No explicit major bug fixes documented for this period; the focus was on building testing infrastructure to reduce regression risk and improve release confidence.
July 2025 monthly summary: Delivered foundational modularization in cosmos/solidity-ibc-eureka. Refactored shared logic from sp1 and Solana programs into standalone packages and introduced Tendermint light client packages (membership, misbehaviour, update client, and combined update client + membership) to improve organization, reusability, and onboarding. No major bugs fixed this month; focus was on architectural improvements and groundwork for future features. This work reduces maintenance costs, accelerates cross-network feature delivery, and enhances code quality.
July 2025 monthly summary: Delivered foundational modularization in cosmos/solidity-ibc-eureka. Refactored shared logic from sp1 and Solana programs into standalone packages and introduced Tendermint light client packages (membership, misbehaviour, update client, and combined update client + membership) to improve organization, reusability, and onboarding. No major bugs fixed this month; focus was on architectural improvements and groundwork for future features. This work reduces maintenance costs, accelerates cross-network feature delivery, and enhances code quality.
January 2025: Delivered a refactor in the anoma-ci-test repository to expand aliases and enforce alphabetical ordering for alias, require, import, and use statements across modules, improving readability, consistency, and maintainability. Commit 6752be78ddd1039dc857963a1cb45abe3f1eccab.
January 2025: Delivered a refactor in the anoma-ci-test repository to expand aliases and enforce alphabetical ordering for alias, require, import, and use statements across modules, improving readability, consistency, and maintainability. Commit 6752be78ddd1039dc857963a1cb45abe3f1eccab.
December 2024: Focused on improving test reliability for ETransaction examples in the anoma-ci-test repository. Delivered an enhancement to capture and assert expected error logs in tests, verifying messages such as 'nullifier already' and 'not committed'. This change strengthens CI confidence, reduces flaky results, and provides clearer failure signals for ETransaction scenarios.
December 2024: Focused on improving test reliability for ETransaction examples in the anoma-ci-test repository. Delivered an enhancement to capture and assert expected error logs in tests, verifying messages such as 'nullifier already' and 'not committed'. This change strengthens CI confidence, reduces flaky results, and provides clearer failure signals for ETransaction scenarios.
Month: 2024-11 — Delivered the IntentPool Nullifier Tracking and Filtering feature in the anoma-ci-test repository, enabling tracking of known nullifiers and filtering out intents with nullifiers already present to prevent duplicates and invalid intents. Added a new nullifiers function to the Intent protocol and its implementations. This work improves protocol correctness, reliability, and downstream processing by reducing invalid/duplicate intents. No major bugs fixed this month; the focus was on feature delivery and code quality. Key deliverables include a single, well-scoped change with associated verification.
Month: 2024-11 — Delivered the IntentPool Nullifier Tracking and Filtering feature in the anoma-ci-test repository, enabling tracking of known nullifiers and filtering out intents with nullifiers already present to prevent duplicates and invalid intents. Added a new nullifiers function to the Intent protocol and its implementations. This work improves protocol correctness, reliability, and downstream processing by reducing invalid/duplicate intents. No major bugs fixed this month; the focus was on feature delivery and code quality. Key deliverables include a single, well-scoped change with associated verification.
October 2024 monthly summary for anoma/anoma-ci-test: Delivered the Enhanced Event System for the Anoma Node by introducing a defevent macro that supports typed event structs, optional field enforcement, and automatic filter module generation. Implemented end-to-end examples and tests for event subscription and filtering, and updated documentation to clarify event struct usage and macro semantics. This work enhances observability, reliability, and integration readiness for downstream systems, while laying the groundwork for robust event-driven workflows in the node.
October 2024 monthly summary for anoma/anoma-ci-test: Delivered the Enhanced Event System for the Anoma Node by introducing a defevent macro that supports typed event structs, optional field enforcement, and automatic filter module generation. Implemented end-to-end examples and tests for event subscription and filtering, and updated documentation to clarify event struct usage and macro semantics. This work enhances observability, reliability, and integration readiness for downstream systems, while laying the groundwork for robust event-driven workflows in the node.

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