Kamanashis Roy Shuva

KAMANASHIS ROY
641.451.4672 ∙ kamanashisroy@gmail.com
leetcode github blogspot portfolio
https://github.com/kamanashisroy
https://www.linkedin.com/in/kamanashis-roy-40616412

SOFTWARE ENGINEER

I gained over 15+ years of experience in design and development ranging from scalable,distributed (call/text/video) web(JSON,gRPC) or ASN.1(L2,L3) based communication server (Linux C/C++) in a modular testable way. The layering of protocol stack, state-pattern, visitor-pattern, code generation ( refer to swig meta-data and aroop compiler backend), functional-patterns, asynchronous-patterns, multi-tasking, unique-ptr, shared-ptr and reactor-patterns are part of my expertise.

Provided that I have backend professional experience, I am not afraid of writing Javascript, C#,Python,Lua(as extension of C backend) for frontend or simulator purposes.

Last year I did a data-science course in UW that covered basic math and tools like sci-kit learning. This year 2025, I took part in the geometric topcoder marathon challenge 60 which reflects the TCP/SCTP window optimization and congestion control where I did some parameter tuning in the algorithm. Also please refer to my dpdk journey for low-level(L1..L4) data-transmission optimization.

PROFESSIONAL EXPERIENCE

Mavenir Systems, Bellevue, WA, USA ∙ 1/2019-4/2025
Provides telecommunication services.

Principal software engineer

4G 5G Radio Access Network
Develop and maintain realtime 4G 5G infrastructure features where the distributed real-time radio-resource management is done. Developed automated PhyscellId addressing on top of 3GPP containerized cloud architecture X2/S1/RRC in a mobility oriented radio network without the usage of GPU. Also worked on neighbor management and load-balancing and other SON(Self Organizing Network similar to Software Defined Network) features.

Layer 4/3 Technologies: SCTP,L4/L3 layer S1, X2, RRC protocol,MAC,RLC,Scheduler,MIMO
Language and framework: C++14,Go, Python, Lua
Code generation: Python, C++ template
Config and Unit testing: Yang,Yaml,XML,JSON,Whitebox testing,Static/Dynamic Analyzer,Valgrind,Code-coverage
Continuous integration:Jenkins,Kubernetes,k8s, Docker, Helm Chart, Python
Debugging: Wireshark, TCMalloc, GDB scripts, KPI analysis,Kafka
Tools: Jira,Jenkins,gcc,gdb,git,Linux,Vim,Klocwork,Sanitizer

Achievements:

• Automated network addressing in distributed radio network cloud with mobility while avoiding network loop
• Decoupled L3/L4 into container/cloud architecture along with gRpc Services.
• Used persistent interface Protobuf between components to allow change while develop/deployment.
• Convert legacy C code to RAII based C++ code for increased stability and extensibility .
  • Used compile time C++ parameter validation.
  • Forcing abstraction API for increased consistency and reliability.
  • Avoid memory corruption, buffer overflow, pointer-invalidation,circular linked-list
    • by using C++ span and lambda .
• Capture runtime events for debugging or AI analysis/telemetry/kafka.
• Develop memory profiler and in memory protocol dissector, generate pcap from coredump.

KAMANASHIS ROY ∙ Page 2 ∙ 641.451.4672 ∙ kamanashisroy@gmail.com

WebRTC RESTFul Backend

Develop and maintain web based Voice/Video/Screen-share/Text service stack signaling+media (like video,audio,text) gateway-server for protocols like SIP,SDP,RTP,RTCP,MSRP,WebRTC,oAuth in distributed, scalable, virtualized setup (refer to my cool python tool for OPUS, H264 rtp debug/record ).

Achievements:

• Deployed hash-based static load balancing to ensure mutual exclusion in thread level
• Reduced memory+timer leak and crash by using unique-pointer and RAII
• Analysed/debugged SIP audio call flow end-to-end and visualized audio quality using gstreamer.

Technologies: C++14, Python, JSON, REST, WebRTC, SIP, SDP, HTTP, DTLS, Websocket, Message Queue, Event-loop,Protobuf,nginx,microservice,gStreamer
Tools:Chrome-browser, Jira,Jenkins,gcc,gdb,git,Linux,Vim,Satic Analyzer,Valgrind

General Electric Transportation/Wabtec as Quest Global, Erie, PA, USA ∙ 7/2016-12/2018
Provides embedded-software services for the locomotive industry.

Senior software engineer
As a scrum-team member designed, developed and tested safety-critical locomotive control protocol features for automated driving(I-ETMS) and PTC(positive train control). Emit error-code based on input or state and supervise based on decision-tree model based on Physics equation and geo-location.

Achievements:

• Reduced the maintenance cost by generating code from csv metadata(please refer to swig).
• Maintained Visual C# (CMake) based managed driving simulator with C++/QNX application.
• Provided static lookup-optimization of design by using hash-code of metadata.
• Reduced the bottleneck of nightly-build time by providing parallel-build enhancements that saves three hours for each individual developer.
• Optimized message-queue for OS Performance.

Technologies: Embedded C/C++, C#, Python, Real-time, Shared-memory, Message-passing, TCP/IP, MISRA
Tools: IBM rational, Jenkins, Perforce, Doxygen, Visual-studio(for simulator), LDRA(unit-testing), Qnx (RTOS), Linux, Makefile, Bash,Bison,Yacc,Flex

SYNCHRONOUS ICT, Dhaka, Bangladesh ∙ 2010-2015
Developers of innovative, groundbreaking communications technology, software, and equipment.

Computer Scientist / Head of R\&D
Led design and development of communications technology products, with the goal of enhancing and optimizing the product portfolio. Coordinated the full development lifecycle for a wide range of applications, systems, and hardware.

Achievements:

• Delivered multiple major projects, including a Shotodol-based VoIP server, Next Dialer(android), a user-space Linux driver for Bluetooth, an Asterisk channel for Sync VoIP protocol, customized SIP channel of 32k lines, a confidential embedded development project(dsp and sip board), Cool Dialer(for Symbian), and diverse other client engagements.
• Drove ongoing developments and enhancements in communications protocols, improving technology to achieve stable service, lower bandwidth, and an unparalleled 6-7 months uptime.
• Boosted performance by introducing non-blocking, event-driven, (asynchronous cooperative non-preemptive multitasking) fiber based horizontally scalable server with lock-free message queue.
• Realized strong revenue growth by creating a Symbian VoIP client with a home-grown communication protocol.
• Recognized for exceptional contributions with a promotion to Head of R\&D.

Technologies: AEL, Aroop, C, C++, Java, LUA, Markdown, PHP, Python, SVG, Vala, Drupal, MySQL, Inkscape, Dia, X11,DPDK
Toos: Android, Asterisk, GCC, GDB, GNUMake, Git, Doxygen, Linux, Symbian, VoiP Board

NOTABLE PROJECTS

• ReactDPDK - Personal: https://github.com/kamanashisroy/reactdpdk A protocol suite with kernel bypass.
• NginCC - Personal: https://github.com/kamanashisroy/ngincc It is event-loop based linux server framework in C++.
• Swig-csv - Personal: https://github.com/kamanashisroy/swig It generates csv-metadata out of C++ class/struct. Thus it separates data from code, which is useful in code generation, decoupling modules and in simulation-tools.
• Aroop - Synchronousict: https://github.com/kamanashisroy/aroop It is a source-to-source compiler.
• Opus stream tool(Python) - Record opus from rtp-stream https://github.com/kamanashisroy/opus_stream_tool
• Algorithm - 90 percentile in leetcode (1K solved) hackerrank-contests problem solving
• MinilM – Shahjalal University of Science & Technology: http://miniim.sourceforge.net/ I developed an open-source multi-protocol instant messaging client based in J2ME(MIDP2).

EDUCATION

Maharishi University of Management, Fairfield, IA, USA ∙ 2015-2018
Master’s in Computer Science

Shahjalal University of Science & Technology, Sylhet, Bangladesh ∙ 2001-2005
Bachelor’s Degree in Computer Science & Engineering

PROFESSIONAL DEVELOPMENT
Oracle Certified Java Programmer

ADDITIONAL COURSES
C++ courses in UW.
Architecture courses in UW.
Data-science courses in UW 520 and 530, scikit Learning