
Petr Sedlacek contributed to the trezor/trezor-firmware repository by engineering robust firmware features and protocol enhancements that improved device security, reliability, and developer experience. He implemented secure storage resets, centralized signing key management, and advanced the THP protocol with session-based communication and cryptographic upgrades using C, Python, and Rust. Petr refactored core modules for maintainability, enforced code style and type safety, and expanded test automation to ensure cross-language consistency. His work addressed protocol robustness, error handling, and build optimization, resulting in a more secure, maintainable, and testable codebase that supports evolving hardware and software requirements for Trezor devices.

October 2025 monthly summary focusing on business value and technical achievements across Trezor firmware and suite. Strengthened cryptography, improved request validation, and stabilized infrastructure, delivering measurable security and reliability improvements with cross-repo impact.
October 2025 monthly summary focusing on business value and technical achievements across Trezor firmware and suite. Strengthened cryptography, improved request validation, and stabilized infrastructure, delivering measurable security and reliability improvements with cross-repo impact.
September 2025 monthly work summary focusing on key accomplishments and outcomes across trezor-firmware and trezor-suite.
September 2025 monthly work summary focusing on key accomplishments and outcomes across trezor-firmware and trezor-suite.
In August 2025, the trezor-firmware team delivered security-focused enhancements, robustness improvements, and maintainability gains that strengthen the product’s trust, compliance, and deployment readiness. Key efforts span centralized signing key management with NRF key support, CLI session reliability fixes, encoding refinements with tests, and maintenance of licensing/headers across components.
In August 2025, the trezor-firmware team delivered security-focused enhancements, robustness improvements, and maintainability gains that strengthen the product’s trust, compliance, and deployment readiness. Key efforts span centralized signing key management with NRF key support, CLI session reliability fixes, encoding refinements with tests, and maintenance of licensing/headers across components.
July 2025 monthly summary for trezor-firmware focused on enabling robust THP support, cleaning up protocol messaging, and strengthening reliability across firmware and tooling. Delivered core THP implementation with CPace support and a session/channel cache to improve performance and stability. Cleaned and typed THP messaging (including ThpError, ButtonAck, and a separation of ThpMessageType from general MessageType), and standardized public_key naming. Updated THP credential derivation path and removed THP qstrings from non-THP builds to reduce binary surface area. Upgraded tooling and APIs to support per-session operation (session-based trezorctl), bumped trezorlib to 14.0, and renamed raise_if_not_confirmed to raise_if_cancelled for clarity. Addressed critical reliability issues and advanced QA: BLE pairing flow fixed using interact, screenshot error resolved on t1, WebUSB/write/error handling improvements, enhanced test utilities (MockAsync, await_result_patched), added THP unit tests, and updated OPTIONS/docs. These changes collectively improve security, reliability, performance, and developer productivity.
July 2025 monthly summary for trezor-firmware focused on enabling robust THP support, cleaning up protocol messaging, and strengthening reliability across firmware and tooling. Delivered core THP implementation with CPace support and a session/channel cache to improve performance and stability. Cleaned and typed THP messaging (including ThpError, ButtonAck, and a separation of ThpMessageType from general MessageType), and standardized public_key naming. Updated THP credential derivation path and removed THP qstrings from non-THP builds to reduce binary surface area. Upgraded tooling and APIs to support per-session operation (session-based trezorctl), bumped trezorlib to 14.0, and renamed raise_if_not_confirmed to raise_if_cancelled for clarity. Addressed critical reliability issues and advanced QA: BLE pairing flow fixed using interact, screenshot error resolved on t1, WebUSB/write/error handling improvements, enhanced test utilities (MockAsync, await_result_patched), added THP unit tests, and updated OPTIONS/docs. These changes collectively improve security, reliability, performance, and developer productivity.
June 2025 monthly summary for trezor/trezor-firmware: Delivered major THP protocol enhancements, strengthened cryptographic stack, and expanded test/CI coverage, driving security, reliability, and faster iteration across environments.
June 2025 monthly summary for trezor/trezor-firmware: Delivered major THP protocol enhancements, strengthened cryptographic stack, and expanded test/CI coverage, driving security, reliability, and faster iteration across environments.
May 2025 development summary for trezor-firmware: Key feature deliveries and stability improvements focused on error handling, protocol support, and storage capacity. Elligator2 error handling standardized using MP_ERROR_TEXT to ensure consistent, maintainable messages across the codebase. THP protocol support integrated by adding a symlink for messages-thp.proto to vendor trezor-common protos, enabling THP messaging in legacy firmware. Storage module presized capacity increased from 12 to 20 items to support more data and future enhancements. These changes reduce debug effort, expand capabilities for legacy devices, and lay groundwork for upcoming features.
May 2025 development summary for trezor-firmware: Key feature deliveries and stability improvements focused on error handling, protocol support, and storage capacity. Elligator2 error handling standardized using MP_ERROR_TEXT to ensure consistent, maintainable messages across the codebase. THP protocol support integrated by adding a symlink for messages-thp.proto to vendor trezor-common protos, enabling THP messaging in legacy firmware. Storage module presized capacity increased from 12 to 20 items to support more data and future enhancements. These changes reduce debug effort, expand capabilities for legacy devices, and lay groundwork for upcoming features.
Monthly work summary for 2025-04 focused on delivering security, observability, and build-optimization improvements in trezor-firmware, with emphasis on business value and maintainability.
Monthly work summary for 2025-04 focused on delivering security, observability, and build-optimization improvements in trezor-firmware, with emphasis on business value and maintainability.
Monthly work summary for 2025-03 focusing on key accomplishments and business value in the trezor-firmware repo.
Monthly work summary for 2025-03 focusing on key accomplishments and business value in the trezor-firmware repo.
February 2025 monthly summary for trezor/trezor-firmware: Delivered targeted improvements in Python code style enforcement and test hygiene, yielding measurable quality and CI benefits. Integrated pb2py into Makefile lint targets and refactored its regex for readability, and removed a debugging print in the Bitcoin device test test_signmessage_pagination to reduce noise without affecting functionality. These changes enhance maintainability, reduce review time, and improve CI signal, aligning with business goals of faster deployments and more reliable releases.
February 2025 monthly summary for trezor/trezor-firmware: Delivered targeted improvements in Python code style enforcement and test hygiene, yielding measurable quality and CI benefits. Integrated pb2py into Makefile lint targets and refactored its regex for readability, and removed a debugging print in the Bitcoin device test test_signmessage_pagination to reduce noise without affecting functionality. These changes enhance maintainability, reduce review time, and improve CI signal, aligning with business goals of faster deployments and more reliable releases.
2024-11 Monthly Summary for trezor/trezor-firmware: Implemented major features to improve secure messaging, buffer handling, async simplicity, modular caching/context, and code quality. Key outcomes include THP messaging enablement with build integration, protobuf wire protocol cleanup and memoryview encoding, async messaging simplification, core caching/context overhaul with enhanced test setup, and documentation/dependencies/code quality improvements. These changes deliver faster feature enablement, more reliable builds, improved performance, and a stronger foundation for future THP and firmware work.
2024-11 Monthly Summary for trezor/trezor-firmware: Implemented major features to improve secure messaging, buffer handling, async simplicity, modular caching/context, and code quality. Key outcomes include THP messaging enablement with build integration, protobuf wire protocol cleanup and memoryview encoding, async messaging simplification, core caching/context overhaul with enhanced test setup, and documentation/dependencies/code quality improvements. These changes deliver faster feature enablement, more reliable builds, improved performance, and a stronger foundation for future THP and firmware work.
October 2024 monthly summary focusing on stabilizing UI-related type stubs and ensuring mocks align with the underlying implementation in the trezor-firmware suite. A targeted bug fix was completed to correct the flow_prompt_backup mock in trezorui2.pyi, preventing mismatches between the Python type stub and the Rust-backed functionality. This reduces test flakiness, improves CI reliability, and strengthens cross-language consistency in the firmware/UI integration.
October 2024 monthly summary focusing on stabilizing UI-related type stubs and ensuring mocks align with the underlying implementation in the trezor-firmware suite. A targeted bug fix was completed to correct the flow_prompt_backup mock in trezorui2.pyi, preventing mismatches between the Python type stub and the Rust-backed functionality. This reduces test flakiness, improves CI reliability, and strengthens cross-language consistency in the firmware/UI integration.
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