Alexander Holodny Email & Phone Number

San Jose, California, United States

AI Group

• Led the development of cross-platform, remotely controlled system service, deployed on thousands of employee’s machines and mobile devices, ensuring compliance with government standards and fail-safety requirements.• Architected various frameworks and components that boosted team performance by 50% through encapsulating common code with clear abstractions and defining standardized interfaces.• Optimized data processing with a constant-memory-usage streaming approach, significantly enhancingperformance and memory efficiency while eliminating critical business constraints.• Successfully outsourced implementation of a large class of features to an external vendor, reducing product support costs by 30% and increased overall efficiency and velocity.• Designed an improved secure communication protocol and implemented high-throughput gateway backend servers for a new fast backend communication approach used across multiple products developed by other teams.

Working in Anoto Host Team at the Software Engineer and Mac Team Lead positions.Team's responsibility is all host development for Windows, Linux and Mac platforms like daemons/services, drivers, SDKs, frameworks and end-user applications.My personal responsibility is launching full stack of Anoto projects for Mac OS providing same functionality as on Windows platform.A lot of legacy projects were rewritten in highly maintainable cross-platform manner, and covered with tests. Some UI projects were written in Swift from scratch.Main programming languages: C++, Swift, C, Obj-C.Anoto projects involved in:IPC (high-speed interprocess communication library) — implemented high quality replacement of SOAP used by all client-server projects.PenDriver (USB and Bluetooth low-level driver) — implemented new universal cross-platform driver and mac-specific part for digital pens.Pen Access Framework (system daemon + API) — implemented new cross-platform pen device multiplexer allowing multiple clients to safely interact with different digital pens.HID Driver (system daemon + API) — implemented new cross-platform service and mac-specific part for some HID-enabled pens to provide Wacom-like functionality.Ink Router (system daemon + API) — implemented new fully cross-platform service used to distribute data from digital pen to different third-party software in background.Screen Driver (system daemon + API) — ported on mac; used to manage some Anoto-enabled screens.Screen Pattern Calibration (library + UI) — implemented from scratch; turns any screen into Anoto Pen-compatible.Ink Framework (library) — designed & implemented to work on host & mobile platforms; used to work with private digital ink formats; also can renders PDFs, MP4 etc.License SDK (library + server) — designed & implemented; PKI-based licensing solution for host projects.Paper SDK (legacy library) — ported on mac; renders pattern as postscript and prints.Also participated in many more projects.

Most interesting and challenging personal tasks were: — implement USB device sharing & virtualization software for macOS;— design and implement PKI-based authentication and secure communication system;— cross platform implementation of secure P2P channel between any peers even when both peers are behind firewall and NAT;— develop internal licensing library for macOS.I've also participated in more macOS & iOS projects.Main programming languages: C++, Obj-C, Swift.USB sharing & virtualization:There was no documented way neither to somehow seize nor to simulate USB devices on macOS.So digging deep into USB specification and sources of USB subsystem (IOUSBFamily) and kernel (Darwin) was required for that task. It was twice-tricky to make that work because when Apple changes something in USB subsystem we've got into troubles like BSODs. Since they did some breaking changes on almost each major release, I've had to fix or sometimes rewrite drivers ASAP. Initially drivers were simulating IOUSBDevice objects. After subsequent macOS release I've had to implement fake IOUSBController simulation. At some point Apple any kind of USB simulations. As a result I've had to implement USB simulation by simulating EHCI controller via fake PCI device at fake PCI bus even with fake Interrupt Controller. It was really tricky to force system to attach bundled EHCI driver to fake PCI device and perform PCI IO. Of course I've had to dig deep into PCI-related docs and sources.I've also implemented two macOS apps using that drivers (via system daemons) — USB Network Gate and Flexihub.Also remote kernel debugging was daily work.PKI implementation:It was also challenging to design system that meets Flexihub requirements like single sign on and secure communication.OpenSSL was used to: issue & validate certificates, run OCSP service, authorize and authenticate both users and servers, communicate via TLS and even DTLS in some cases. Implementation is cross platform.