June 2025 performance summary: Across LedgerHQ/ledger-secure-sdk and LedgerHQ/speculos, delivered high-impact features and stability improvements that strengthen security interoperability, reliability, and device variant support. Highlights include U2F/HID security key integration with refined APDU routing; IO subsystem stabilization and heartbeat improvements; BLE Flex UUID support for multiple Ledger targets; and preparatory NFC Power Tag handling to enable future power management. These changes reduce integration risk, improve cross-device compatibility, and position the platform for broader hardware support and future NFC capabilities.

May 2025 monthly summary focusing on key features delivered, major fixes, impact, and skills demonstrated across LedgerHQ/ledger-secure-sdk and LedgerHQ/speculos. Highlights include robustness enhancements to APDU I/O, multi-interface support, and SEProxy protocol improvements enabling more reliable hardware interactions.

April 2025 – LedgerHQ/ledger-secure-sdk: Delivered security, reliability, and scalability improvements across NFC, IO, BLE, and protocol layers. Key features delivered include PIN-Protected APDU Execution to ensure commands are processed only after PIN validation; NFC Reader Mode Enhancements to improve reliability in NFC/ticker events including legacy BOLOS environments; BLE Enhancements providing multi-profile support and optimized initialization to avoid re-fetching a random address; NBGL Data Capacity Expansion to support larger serialized payloads and newer hardware features; Ledger Protocol improvements to avoid transmitting empty MTU chunks. Major bugs fixed include preventing empty MTU chunk transmissions to improve protocol reliability. Overall, these changes strengthen security, connectivity, and UI data handling, reducing failure modes and enabling smoother integration with newer hardware like Flex and Stax. Technologies demonstrated include low-level protocol hardening, secure UX design, cross-interface IO reliability, BLE protocol handling, and NBGL data modeling across devices.

March 2025 performance summary for LedgerHQ/ledger-secure-sdk: focused on reliability and interoperability enhancements. Implemented critical low-level buffer handling fix and reinforced USB HID/WebUSB interaction to prevent disruptions, delivering improved data integrity for APDU processing and more robust cross-class USB support. Business impact includes fewer field-reported buffer issues and reduced USB disconnections during U2F operations.

February 2025: Ledger-secure-sdk delivered IO Stack Modernization with OS IO Integration. Introduced consolidated IO configurations and new defines REVAMPED_IO and USE_OS_IO_STACK, enabling OS-level IO integration across targets. Refactored Makefiles to unify IO handling and streamline build across features. No major bugs reported this month; this work establishes a robust foundation for future IO improvements and cross-target portability. Commit reference: 7968333824480a0a12b9156799e5079ba3378f4d.

Month 2024-11 focused on reliability and correctness in the inactivity shutdown flow within Ledger Secure SDK. Implemented a targeted fix to synchronize ticker data with the layout description to maintain proper inactivity shutdown behavior and prevent state inconsistencies.