Inboxbooster

We Fix Email in Spam

JVM Bytecode Engineer (full remote)

$100K - $150K / 0.50% - 1.50%
Location
San Francisco, CA, US / Remote (US)
Job Type
Full-time
Experience
Any (new grads ok)
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Nicolas Toper
Nicolas Toper
Founder

About the role

Shape the Future of Computing

We're building technology that automatically parallelizes Java applications by transforming bytecode post-compilation. Our proof of concept already shows a 2.8x speedup on real workloads without requiring source code changes. Now, we're looking for a brilliant JVM engineer to help turn this into a game-changing product.

For a deep dive into our current approach and early results, check out our recent technical blog post showing 2.8x speedup through automatic bytecode parallelization or here (for a really deep dive).

The Role

You'll work directly with our founding team to evolve our automatic parallelization engine from proof-of-concept to production-ready system. You'll dive deep into bytecode manipulation, control flow analysis, and concurrent execution patterns while helping shape our product strategy.

The Challenge

  • Transform our working prototype into a robust, production-grade system
  • Extend parallelization capabilities to handle complex scenarios (branching, object references, exceptions)
  • Design and implement sophisticated program analysis techniques
  • Build tooling to make parallel execution safe and efficient across diverse codebases
  • Help shape our product roadmap based on real-world use cases

What You Bring

Must Have

  • Comfort with startup "lifestyle" (high expectation, high pressure, uncertainty, instability but a career defining opportunity if it works out)
  • Deep understanding of JVM internals and bytecode manipulation
  • Strong grasp of Java concurrency and thread safety principles
  • Experience with control flow analysis and program transformation
  • Solid background in parallel computing concepts
  • Excellent problem-solving skills and attention to detail
  • Strong written communication skills for remote collaboration
  • Comfort with ambiguity and rapid iteration

Nice to Have

  • Experience with BCEL or similar bytecode manipulation libraries
  • Background in building developer tools or performance optimization systems
  • Familiarity with static analysis techniques
  • Experience turning prototypes into production systems
  • Previous remote work experience
  • Startup experience

Why Join Us

The Opportunity

  • Work on cutting-edge technology that could revolutionize software performance
  • Shape the direction of a foundational product from its early stages
  • Join as an early engineer with significant equity upside
  • Learn and grow rapidly in a fast-paced environment
  • Work remotely with a focused, talented team

Benefits (US-based)

  • Comprehensive health insurance
  • 401(k) plan
  • FSA availability
  • Remote work setup
  • Regular team on-site for collaboration

Our Work Style

  • Fully remote with quarterly in-person team meetings
  • High autonomy and ownership
  • Direct communication and rapid feedback
  • Focus on impact over process
  • Learn and adapt quickly

About Us

We're InboxBooster, an early-stage startup that began by solving critical email deliverability problems - helping companies stay out of spam folders. While building our email platform, we discovered an opportunity to dramatically improve software performance through automatic parallelization.

This new direction emerged from our hands-on experience with high-performance systems. Our proof of concept already shows dramatic speedups on real workloads, and we're now building out a dedicated team to turn this into a transformative product.

We believe computation is a cornerstone of modern society, and making it more efficient can have a massive impact. We're looking for engineers who are excited by both the technical challenge and the opportunity to shape a new direction.

Next Steps

If you're excited about pushing the boundaries of software performance and want to join an early-stage startup with massive potential impact, we'd love to talk. Send us:

  1. Your background (resume, LinkedIn, or just tell us your story)
  2. What interests you about this role
  3. Any relevant projects or experiences you'd like to highlight

We look forward to hearing from you!

About the interview

Our process is straightforward and respectful of your time:

  1. Initial Interview - Get to know each other and discuss your background (10 min)
  2. Technical Assessment - A take-home exercise (2 hours maximum)
  3. Technical Discussion - Review your solution and dive deeper into the technical aspects (1 hour)
  4. Closing Interview - Discuss working together and answer any remaining questions (30 min)

About Inboxbooster

We’re Inboxbooster. We’re building tools to remake email from the ground up. Our first tool is a pixel tracker allowing you to detect deliverability issues; the second is a tool to resolve them. We just closed a $2M funding round and achieved product/market fit, and now we’re looking to build the team. Our two websites: https://inboxbooster.com and https://manycore.io, to learn more

Inboxbooster
Founded:2016
Team Size:3
Location:San Francisco
Founders
Marcus Engene
Marcus Engene
Founder
Nicolas Toper
Nicolas Toper
Founder