Freelance Software Engineer
About the role
This short-term contract role is focused on enhancing the security and functionality of RHEL 9 servers by enabling file uploads to Perplexity.ai while maintaining strict egress controls. The position requires a senior Linux and network security engineer to analyze outbound traffic, identify the necessary domains, IPs, and CIDRs for successful uploads, and develop a minimal, auditable, and secure outbound firewall ruleset. The engineer will also be responsible for implementing a command line prototype compatible with Perplexity.ai to validate the solution. The project is urgent and must be completed within 3–5 days, delivering a robust, well-documented solution suitable for enterprise environments.
Responsibilities
- Analyze outbound network traffic on RHEL 9 servers during Perplexity.ai upload attempts
- Identify all required domains, IP addresses, and CIDR ranges, including Cloudflare-backed endpoints
- Develop and document a minimal, secure, and auditable iptables ruleset to enable uploads while maintaining a default DROP policy
- Implement a command line prototype tool to validate file upload functionality to Perplexity.ai
- Ensure the solution is robust, enterprise-ready, and accompanied by clear documentation for future audits and maintenance
- Collaborate with stakeholders to ensure all security and operational requirements are met within the project timeline
Skills And Requirements
- Extensive experience with RHEL 9, Linux networking, and iptables configuration
- Deep understanding of egress firewall policies and best practices for secure server environments
- Proven ability to analyze and troubleshoot network traffic, including the use of tools such as tcpdump and Wireshark
- Familiarity with Cloudflare infrastructure and dynamic endpoint management
- Strong scripting skills for developing command line prototypes (e.g., Bash, Python)
- Ability to produce clear, comprehensive documentation for technical and non-technical audiences
- Experience working in enterprise or high-security environments
- Availability for immediate start and ability to deliver within a 3–5 day timeframe
About Twine Twine is a leading freelance marketplace connecting top freelancers, consultants, and contractors with companies needing creative and tech expertise. Trusted by Fortune 500 companies and innovative startups alike, Twine enables companies to scale their teams globally.
Our Mission Twine's mission is to empower creators and businesses to thrive in an AI-driven, freelance-first world.
About Twine
Twine connects companies to over 750,000 freelance experts across 190+ countries. We enable flexible work opportunities for so many talented people. Twine covers tech, creative and AI – Software development, graphic design, animation, marketing, video products and everything in between.
STARTUPS (www.twine.net) Companies need a flexible and global workforce to keep competitive. However, they struggle to find specific experts to match their needs. If you have niche technical/creative requirements or need a freelancer in a specific location – we can help you.
FREELANCERS and CONSULTANTS (www.twine.net/freelancers) If you're a freelancer or consultant, take control and choose which projects you want to work on. Build your portfolio with Twine and find interesting jobs from all over the world.
AI COMPANIES (www.twine.net/ai) If you're a company that uses machine learning and needs audio-visual datasets, we can use our network of diverse freelancers to build this for you. Text to speech, video, actors, presenters, and more.
Freelance Software Engineer
About the role
This short-term contract role is focused on enhancing the security and functionality of RHEL 9 servers by enabling file uploads to Perplexity.ai while maintaining strict egress controls. The position requires a senior Linux and network security engineer to analyze outbound traffic, identify the necessary domains, IPs, and CIDRs for successful uploads, and develop a minimal, auditable, and secure outbound firewall ruleset. The engineer will also be responsible for implementing a command line prototype compatible with Perplexity.ai to validate the solution. The project is urgent and must be completed within 3–5 days, delivering a robust, well-documented solution suitable for enterprise environments.
Responsibilities
- Analyze outbound network traffic on RHEL 9 servers during Perplexity.ai upload attempts
- Identify all required domains, IP addresses, and CIDR ranges, including Cloudflare-backed endpoints
- Develop and document a minimal, secure, and auditable iptables ruleset to enable uploads while maintaining a default DROP policy
- Implement a command line prototype tool to validate file upload functionality to Perplexity.ai
- Ensure the solution is robust, enterprise-ready, and accompanied by clear documentation for future audits and maintenance
- Collaborate with stakeholders to ensure all security and operational requirements are met within the project timeline
Skills And Requirements
- Extensive experience with RHEL 9, Linux networking, and iptables configuration
- Deep understanding of egress firewall policies and best practices for secure server environments
- Proven ability to analyze and troubleshoot network traffic, including the use of tools such as tcpdump and Wireshark
- Familiarity with Cloudflare infrastructure and dynamic endpoint management
- Strong scripting skills for developing command line prototypes (e.g., Bash, Python)
- Ability to produce clear, comprehensive documentation for technical and non-technical audiences
- Experience working in enterprise or high-security environments
- Availability for immediate start and ability to deliver within a 3–5 day timeframe
About Twine Twine is a leading freelance marketplace connecting top freelancers, consultants, and contractors with companies needing creative and tech expertise. Trusted by Fortune 500 companies and innovative startups alike, Twine enables companies to scale their teams globally.
Our Mission Twine's mission is to empower creators and businesses to thrive in an AI-driven, freelance-first world.
About Twine
Twine connects companies to over 750,000 freelance experts across 190+ countries. We enable flexible work opportunities for so many talented people. Twine covers tech, creative and AI – Software development, graphic design, animation, marketing, video products and everything in between.
STARTUPS (www.twine.net) Companies need a flexible and global workforce to keep competitive. However, they struggle to find specific experts to match their needs. If you have niche technical/creative requirements or need a freelancer in a specific location – we can help you.
FREELANCERS and CONSULTANTS (www.twine.net/freelancers) If you're a freelancer or consultant, take control and choose which projects you want to work on. Build your portfolio with Twine and find interesting jobs from all over the world.
AI COMPANIES (www.twine.net/ai) If you're a company that uses machine learning and needs audio-visual datasets, we can use our network of diverse freelancers to build this for you. Text to speech, video, actors, presenters, and more.