Speakers : � Mr. Varad Patil | Mr. Sumanto Kar | Ms. Shanthi Priya | Mr. Aditya Minocha

Prof. Prabhu Ramachandran (Aerospace Dept. , IIT Bombay)� Prof. Kannan Moudgalya (Director EduPyramids, Former Professor IIT Bombay)

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• FOSSEE stands for Free/Libre and Open-Source Software for Education.

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• It’s a project based at IIT Bombay and supported by the National Mission on Education through ICT (Ministry of Education, Government of India).

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• The main goal of FOSSEE is to promote the use of open-source software in academia, research, and industry, especially in India.

About FOSSEE

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• Why? Because commercial software in engineering and science (like MATLAB, OrCAD, Ansys) is often very expensive and creates dependency. Open-source alternatives are free, customizable, and community-driven.

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FOSSEE contributes by :

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• Creating textbook companions (where solved examples from standard textbooks are recreated using open-source tools)
• Conducting workshops, hackathons, and internships for students

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About FOSSEE

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• eSim is an open-source Electronic Design Automation (EDA) tool developed by FOSSEE at IIT Bombay.

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• It helps with circuit design, simulation, and analysis — basically what commercial tools like OrCAD or PSpice do, but in a free and open way.

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Key Features of eSim:

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• Schematic capture: draw circuits using a graphical interface

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About eSim

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• Simulation: run simulations using Ngspice (analog circuits) and Verilator (digital/HDL simulation) Co-simulation: integrate analog + digital in the same design.
• OpenModelica support: model and simulate complex systems

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eSim integrates multiple open-source components:

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• KiCad → for schematic capture and PCB design Ngspice → for circuit simulation
• Verilator → for HDL co-simulation OpenModelica → for system modeling

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About eSim

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• Problem Statement & Rationale
• Technical Context
• Process Design Kit (PDKs)
• Containerization Frameworks
• Methodology
• Constraints and Limitations
• Findings and Significance
• Concluding Remarks

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Structure of Discussion

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Problem: Complex setup procedures, along with platform dependent libraries, act as barriers to wider adoption.

• Linux software distribution: fragmented, dependency hell.
• Traditional package managers (.deb, .rpm) tied to OS versions.
• Students/researchers often lack admin privileges in labs.
• eSim integrates KiCad, Ngspice, Verilator, OpenModelica.

Problem Statement & Rationale

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Technical Context

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eSim’s Window

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Lets Look for some example

• Voltage regulator

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Lets Look for another example with�RISC - V

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8-bit MIPS (Microprocessor without Interlocked Pipeline Stages) Processor: A Verilog-Based Approach

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• Integration with open silicon PDKs such as SkyWater130, IHP Open PDK (Ongoing Marathon 2025 and GF180(Work in Progress).
• Unified through Ubuntu-based toolchains — enabling reproducible builds and version-pinned package isolation.

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• Each PDK container encapsulates:
• Device models
• Layout rules
• Technology files for Ngspice/Verilator interfaces
• Managed via Python bindings and deployed as modular Snaps.

Process Design Kit (PDKs)

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• Snapcraft Integration:
• Secure, confined environments with auto-updates via Ubuntu Store.
• Eliminates dependency drift and supports multi-channel versioning.
• Best for multi-user academic labs.

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• Docker Framework:
• Offline availability during workshop/exams.
• Creates a pre-configured runtime environment.

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• Both frameworks facilitate immutable, reproducible design environments, reducing onboarding friction in academic and research labs.

Containerization Frameworks

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Methodology

• Define reproducible simulation environment on Ubuntu LTS.
• Containerize eSim core modules using Snapcraft and Docker.
• Integrate open PDKs via Python-based middleware.
• Validate designs on Ubuntu CI pipelines with automated regression tests.
• Benchmark performance, portability, and build consistency across architectures.
• Deploy AI layer for design parameter optimization and predictive fault analysis.

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Constraints and Limitations

• Limited GPU acceleration for Ngspice within confined Snap environments.
• Incomplete multi-arch support for certain PDK toolchains
• Snap sandboxing restricts direct file system access during complex hierarchical simulations.
• AI-assisted modules currently experimental; require external compute nodes.

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Findings and Significance

• Ubuntu LTS provides unmatched reproducibility and CI integration for EDA workflows.
• Snap and Docker deployment models reduced environment setup.
• Cross-architecture portability achieved without manual dependency resolution.
• Demonstrated feasibility of fully containerized open EDA stack for academia and industry.
• Established foundation for cloud-based simulation on Ubuntu Server.

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Our Activity at FOSSEE

• Research Migration Project(Newly started)
• Reproduce already published work using eSim.
• Work must be the outcome of a peer-reviewed process in reputed journals, conferences, or workshops
• The proposed published work is the outcome of commercial tools viz. PSpice, Multisim, etc. use.
• Circuit Simulation Project
• The contributor gets
• Recognition on the website,
• A certificate from FOSSEE, IIT Bombay
• We have 360+ verified submissions throughout the country
• Lab Migration Project
• The contributor gets
• Recognition on the website,
• A certificate from FOSSEE, IIT Bombay
• We have migrated 8 Institutional Labs to Open Source

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What we offer ?

• FOSSEE Fellowships & Internships

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• Winter Internship 2025 ( Ongoing )
• FOSSEE Semester Long Internship 2025 ( Ongoing )
• FOSSEE Summer Fellowship 2025
• Winter Internship 2024
• FOSSEE Fellowship 2024
• FOSSEE Semester Long Internship 2024
• Winter Internship 2023
• Semester Long internship 2023
• Summer Fellowship 2022
• Spoken Tutorial Fellowship 2022
• And before 2021 as well …

Marathon Statistics:

2000+ registrations�Over 100 winners�Around 9 designs sent to Fab�Published Papers

Conducted Webinars/Workshops with various institutions for promoting eSim

Fellowship/Internships Statistics in 2025:

• 30+ Fellows
• 29 Semester Long Interns

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eSim Hardware Workshop

with 3000 participants in 2019

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A repository of 600+ circuits contributed from India and abroad

Postal campaign to reach out to many people!

Our Outreach

• FOSSEE Team Members
• Undergraduate, graduate and researchers from all over the country and abroad
• Various industry partners
• Coordinating with the teams of Swadeshi Processors (like AJIT, SHAKTI and VEGA)
• Earlier collaborated with the Google SkyWater
• Connecting with IHP Fab, Germany
• Part of the Indian Semiconductor Mission
• Reaching out to many other Open Source Fabs!!!

Our Collaborators

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Concluding Remarks

• The synergy between Ubuntu’s container ecosystem and eSim’s modular architecture establishes a sustainable model for open hardware development.
• Standardizing EDA pipelines on Ubuntu enhances collaboration, reproducibility, and global accessibility.
• Future work:
• AI inference directly within Snap containers
• RISC-V optimized PDK builds
• Integration with Ubuntu Core for edge EDA systems
• eSim on Ubuntu demonstrates how open infrastructure can scale precision design tools for the next generation of researchers.

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Thank you!

Q U E S T I O N S ?

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November 15, 2025

Project Link: https://github.com/FOSSEE/eSim

Contact: varadpatilofficial@gmail.com, � sumantokar@iitb.ac.in, contact-esim@fossee.in

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Speaker: Mr. Varad Patil , Mr. Sumanto Kar

Contributors:

Ms. Shanthi Priya | Mr. Aditya Minocha

Prof. Prabhu Ramachandran (Professor IIT Bombay)�Prof. Kannan Moudgalya (Director EduPyramids, Former Professor IIT Bombay)