
Rhys Bartels-Waller contributed to the input-output-hk/lace and cardano-js-sdk repositories, delivering browser extension wallet features, blockchain integrations, and hardware wallet support. He engineered solutions such as Sentry error monitoring, Blockfrost API integration, and Trezor onboarding, focusing on reliability, security, and user experience. Using TypeScript, JavaScript, and React, Rhys improved CI/CD pipelines, optimized polling and caching, and enhanced cryptographic signing workflows. His work included Docker-based build upgrades, dependency management, and DevOps automation. By aligning release management with robust testing and documentation, Rhys ensured maintainable, production-ready code that addressed both end-user needs and developer efficiency across evolving Cardano projects.

September 2025: Delivered broader hardware wallet support and security improvements across cardano-js-sdk and lace. Key outcomes include Trezor derivation type support and getXpub fix, per-wallet Trezor config in wallet metadata, onboarding derivation type selection for Trezor on Lace, CI and dependency security hardening, and maintainability-focused refactors. Business value: improved wallet interoperability, stronger security posture, faster onboarding, and a more scalable codebase.
September 2025: Delivered broader hardware wallet support and security improvements across cardano-js-sdk and lace. Key outcomes include Trezor derivation type support and getXpub fix, per-wallet Trezor config in wallet metadata, onboarding derivation type selection for Trezor on Lace, CI and dependency security hardening, and maintainability-focused refactors. Business value: improved wallet interoperability, stronger security posture, faster onboarding, and a more scalable codebase.
August 2025 monthly summary focusing on key accomplishments, business value, and technical achievements across two repositories: input-output-hk/cardano-js-sdk and input-output-hk/lace. Delivered major feature work, stability improvements, and UX enhancements that streamline signing workflows, improve interoperability with upstream libraries, and modernize the build and dependency landscape.
August 2025 monthly summary focusing on key accomplishments, business value, and technical achievements across two repositories: input-output-hk/cardano-js-sdk and input-output-hk/lace. Delivered major feature work, stability improvements, and UX enhancements that streamline signing workflows, improve interoperability with upstream libraries, and modernize the build and dependency landscape.
April 2025 monthly summary focusing on business value and technical achievements for input-output-hk/lace. Focused on performance, security, and CI/CD reliability. Delivered two user-facing features and one security fix, plus important DevOps improvements.
April 2025 monthly summary focusing on business value and technical achievements for input-output-hk/lace. Focused on performance, security, and CI/CD reliability. Delivered two user-facing features and one security fix, plus important DevOps improvements.
March 2025 monthly summary focusing on key business and technical outcomes. Delivered KoraLabs Handle Resolution Integration in the cardano-js-sdk stack, enabling Cardano handle resolution via the KoraLabs public API. Implemented KoraLabsHandleProvider with support for handle resolution, health checks, and policy ID retrieval. Added unit tests and updated CI workflows to validate and maintain the feature. No major bugs reported this month; efforts focused on feature delivery and improving maintainability. Overall, this work enhances interoperability for downstream clients and reduces manual lookup friction.
March 2025 monthly summary focusing on key business and technical outcomes. Delivered KoraLabs Handle Resolution Integration in the cardano-js-sdk stack, enabling Cardano handle resolution via the KoraLabs public API. Implemented KoraLabsHandleProvider with support for handle resolution, health checks, and policy ID retrieval. Added unit tests and updated CI workflows to validate and maintain the feature. No major bugs reported this month; efforts focused on feature delivery and improving maintainability. Overall, this work enhances interoperability for downstream clients and reduces manual lookup friction.
February 2025 ( Lace - input-output-hk/lace ) Key features delivered: - Browser Extension Wallet v1.20.0 release, delivering user-facing features including renaming wallets, governance tab, restored activity feed, improved input focusing, optimized caching, refined landing page, and opt-in debug logging. - Release engineering and documentation completed with version bump to v1.20.0 and release notes published to accompany the release. Major bugs fixed: - A set of release-notes–documented fixes associated with the v1.20.0 rollout, addressing UI consistency, input handling, and caching-related issues to improve reliability and user experience. Overall impact and accomplishments: - Substantial improvement to user experience and governance participation via the feature set in v1.20.0. - Smoother onboarding and day-to-day usage through UI refinements, activity feed restoration, and targeted performance optimizations. - Demonstrated disciplined release engineering and thorough documentation, enabling easier adoption and maintainability. Technologies/skills demonstrated: - Browser extension development (JavaScript/TypeScript), UI/UX improvements, and performance optimization (caching). - Release engineering, semantic versioning, and release-note documentation. - Feature delivery with end-user value and maintainable code changes.
February 2025 ( Lace - input-output-hk/lace ) Key features delivered: - Browser Extension Wallet v1.20.0 release, delivering user-facing features including renaming wallets, governance tab, restored activity feed, improved input focusing, optimized caching, refined landing page, and opt-in debug logging. - Release engineering and documentation completed with version bump to v1.20.0 and release notes published to accompany the release. Major bugs fixed: - A set of release-notes–documented fixes associated with the v1.20.0 rollout, addressing UI consistency, input handling, and caching-related issues to improve reliability and user experience. Overall impact and accomplishments: - Substantial improvement to user experience and governance participation via the feature set in v1.20.0. - Smoother onboarding and day-to-day usage through UI refinements, activity feed restoration, and targeted performance optimizations. - Demonstrated disciplined release engineering and thorough documentation, enabling easier adoption and maintainability. Technologies/skills demonstrated: - Browser extension development (JavaScript/TypeScript), UI/UX improvements, and performance optimization (caching). - Release engineering, semantic versioning, and release-note documentation. - Feature delivery with end-user value and maintainable code changes.
January 2025 (Lace) — Focused on reliability, performance, and release readiness. Delivered three key features with impactful business value and prepared the project for a clean release cycle. No explicit major bugs fixed this month; instead, we consolidated improvements that enhance user experience and developer experience.
January 2025 (Lace) — Focused on reliability, performance, and release readiness. Delivered three key features with impactful business value and prepared the project for a clean release cycle. No explicit major bugs fixed this month; instead, we consolidated improvements that enhance user experience and developer experience.
December 2024 — Lace repository: Delivered release management and UX improvements focusing on stability, test reliability, and groundwork for upcoming features. Key outcomes include version bumps (no functional changes) and a Sign Message Result UX enhancement with tests updated. No major functional bugs were fixed; emphasis on maintainability, release discipline, and user clarity in signing flows.
December 2024 — Lace repository: Delivered release management and UX improvements focusing on stability, test reliability, and groundwork for upcoming features. Key outcomes include version bumps (no functional changes) and a Sign Message Result UX enhancement with tests updated. No major functional bugs were fixed; emphasis on maintainability, release discipline, and user clarity in signing flows.
November 2024: Focused on delivering business-value features, stabilizing production tooling, and simplifying architecture across lace and cardano-js-sdk. Emphasis on performance, reliability, and developer experience.
November 2024: Focused on delivering business-value features, stabilizing production tooling, and simplifying architecture across lace and cardano-js-sdk. Emphasis on performance, reliability, and developer experience.
In 2024-10, the lace repository delivered a key feature: Sentry error monitoring integration for the browser extension, coupled with an enhanced release pipeline. The work strengthens production observability, reduces mean time to detect and fix errors, and improves release quality by aligning source map uploads with the package build step. This was achieved through CI workflow updates and dedicated commits that initialize and configure Sentry in the release process.
In 2024-10, the lace repository delivered a key feature: Sentry error monitoring integration for the browser extension, coupled with an enhanced release pipeline. The work strengthens production observability, reduces mean time to detect and fix errors, and improves release quality by aligning source map uploads with the package build step. This was achieved through CI workflow updates and dedicated commits that initialize and configure Sentry in the release process.
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