Backend Software Engineer

Job Title: Senior Linux Kernel Engineer

Experience: 5–10 Years

Location: Bangalore / Chennai

Domain: Enterprise Linux / Kernel Development

Job Summary

We are seeking a highly skilled Senior Linux Kernel Engineer with deep expertise in kernel development, debugging, and performance optimization. The role involves working on enterprise-grade Linux distributions, kernel lifecycle management, security patching, and low-level hardware integration.

Key Responsibilities

1. Kernel Lifecycle & Maintenance

• Lead kernel upgrade strategies (e.g., LTS migrations such as 5.15 → 6.x) while ensuring stability and compatibility.
• Perform patch porting across kernel versions, resolving API and dependency conflicts.
• Track and mitigate security vulnerabilities by monitoring CVEs and upstream sources (e.g., LKML).
• Backport critical fixes to production kernels without impacting system stability.

2. Debugging & System Stability

• Act as an escalation point for kernel panics and system crashes.
• Perform post-mortem analysis using kdump, crash, and gdb.
• Debug early boot issues (UEFI, initramfs, kernel initialization).
• Conduct performance analysis using eBPF, ftrace, and perf to optimize system behavior.

3. Driver Development & Hardware Integration

• Design, develop, and maintain device drivers (network, storage, GPU, or character devices).
• Work closely with hardware through DMA, interrupts (MSI-X), and register-level programming.
• Maintain out-of-tree drivers using DKMS or similar frameworks.
• Ensure compatibility of drivers across kernel updates.

Required Technical Skills

• Programming: Strong expertise in C (mandatory) and C++
• Kernel Internals: Deep understanding of:
• Virtual File System (VFS)
• Memory Management (MMU, Paging)
• Process Scheduler
• Linux Networking Stack
• Debugging Tools:
• kdump, crash, gdb
• kprobes, trace-cmd, ftrace
• perf, valgrind
• Hardware debugging tools (JTAG, Serial Console)
• Build Systems:
• Kbuild, Makefiles
• Kernel packaging (RPM/Debian)
• Security:
• Experience with CVE patching and backporting
• Knowledge of SELinux/AppArmor
• Kernel hardening (FIPS, KSPP)

Preferred Skills

• Experience contributing to open-source kernel projects
• Familiarity with Linux Kernel Mailing List (LKML) workflows
• Exposure to enterprise Linux distributions (RHEL, Ubuntu, SUSE)
• Experience with performance tuning and system optimization at scale

1. Core Programming (C Language)

• Must have strong hands-on experience in C programming
• Comfortable with pointers, memory management, and low-level concepts

2. Kernel Internals Expertise

• Should have worked in at least one subsystem:
• VFS / File Systems
• Memory Management
• Scheduler / Networking

3. Debugging & Crash Analysis

• Experience handling kernel panics
• Hands-on with vmcore analysis tools

4. Security & Patching

• Understanding of CVE fixes and backporting

5. Driver Development

• Experience in writing or maintaining device drivers

6. Performance & Advanced Debugging

• Exposure to eBPF, ftrace, perf

7. Hardware-Level Understanding

• Knowledge of DMA, interrupts, hardware interaction

Soft Skills

• Strong analytical and problem-solving abilities
• Excellent communication skills
• Ability to work independently and in collaborative environments
• Quick learner with adaptability to new technologies

Required Skills:

• 3+ years of experience with development in JAVA technology.
• Strong Java Basics
• SpringBoot or Spring MVC
• Hands-on experience with Relational Databases (SQL query or Hibernate) + Mongo (JSON parsing)
• Proficient in REST API development
• Messaging Queue (RabitMQ or Kafka)
• Microservices
• Any Caching Mechanism
• Good at problem-solving

Good to Have Skills:

• 4+ years of experience in using Java/J2EE tech stacks
• Good understanding of data structures and algorithms.
• Excellent analytical and problem-solving skills.
• Ability to work in a fast-paced internet start-up environment.
• Experience in technical mentorship/coaching is highly desirable.
• Understanding of AI/ML algorithms is a plus.

We're on a mission to make it possible for every person, team, and company to be able to tailor their software to solve any problem and take on any challenge. Computers may be our most powerful tools, but most of us can't build or modify the software we use on them every day. At Notion, we want to change this with focus, design, and craft.

We've been working on this together since 2016, and have customers like Pixar, Mitsubishi, Figma, Plaid, Match Group, and thousands more on this journey with us. Today, we're growing fast and excited for new teammates to join us who are the best at what they do. We're passionate about building a company as diverse and creative as the millions of people Notion reaches worldwide.

Millions of people use Notion — and this number is increasing every day. That means a million people trust us to deliver a fast, reliable, and secure experience, and we value this more than anything. We want to keep earning trust, while also continuing to amaze our users with the tools they can build in Notion. This is where you come in — to help us forge a performant and reliable path forward to the future.

• Write clean, secure, tested, and documented code.
• Design & enhance the Notion platform with new capabilities, as and when the need arises.
• Contribute to monitoring & scaling the architecture of the platform and the infrastructure.
• Write technical documentation, and contribute to determining internal processes.
• Contribute to recruiting of new backend employees

• 6+ years of experience building scalable platforms. 
• Good understanding of database (Relational Or Nosql) internals like transactions, indexes. Experience in schema design.
• 2+ years of experience working on the AWS platform, and acquaintance with technologies like Elastic Beanstalk, AWS Lambda, Elastic Load Balancer.
• Good understanding of docker internals.
• Good communication skills, good leadership skills, attention to detail, a sound understanding of algorithms, and object-oriented programming.

• You're proficient with any part of our technology stack: React, TypeScript, Node.js, Memcached, Postgres, Docker, and Elasticsearch.
• You've heard of computing pioneers like Ada Lovelace, Douglas Engelbart, Alan Kay, and others—and understand why we're big fans of their work.
• You have interests outside of technology, such as in art, history, or social sciences.

Our customers come from all walks of life and so do we. We hire great people from a wide variety of backgrounds, not just because it's the right thing to do, but because it makes our company stronger. If you share our values and our enthusiasm for small businesses, you will find a home at Notion.

Notion is proud to be an equal opportunity employer. We do not discriminate in hiring or any employment decision based on race, color, religion, national origin, age, sex (including pregnancy, childbirth, or related medical conditions), marital status, ancestry, physical or mental disability, genetic information, veteran status, gender identity or expression, sexual orientation, or other applicable legally protected characteristic. Notion considers qualified applicants with criminal histories, consistent with applicable federal, state and local law. Notion is also committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If you need assistance or an accommodation made due to a disability, please let your recruiter know.

Job Description

Primary Skills

• Server Side (Java) & AWS serverless framework.
• Must have hands-on experience on serverless framework.
• Design knowledge/experience of cloud-based web application. Familiarity with software design representation tools like astah, visio etc.
• Must have good experience on AWS (Overall knowledge, EC2 Volume, EC2 Security Group, EC2 AMI, Lambda, S3, AWSbackup, CloudWatch, CloudFormation, CloudTrail, IAM, SecretsManager, StepFunction, CostExplorer, KMS, VPC/Subnet)
• Understanding business requirements w.r.t UI/UX.
• Working experience on development/staging/production servers.
• Good testing and verification skills
• Knowledge on SSL certificates and encryption.
• Knowledge on Docker containerization.

Soft Skills

• Excellent interpersonal, oral and writing communication skills.
• Strong Analytical and Problem-solving skills.
• Should have skills to understand and analyzecustomers requirements and expectations.
• Must have experience in interaction with customer
• Work experiences with international cross-culture teams (Good to have)

Secondary SKills

• Scripting using Python
• Good to have knowledge of identity management
• UI/UX
• Knowledge of ReactJS/typescript/bootstrap
• Understanding business usecases w.r.t UI/UX
• Fixing issues wrt to integration on cloud(front end/back end/system/services APIs)