Senior Software Engineer, Trust & Safety

Replit2 days ago

Location

Foster City, CA

Type

Full Time

Salary

USD 210,000 – 265,000

Level

Senior

Role

Senior Software Engineer

Posted

May 26, 2026

Full TimeSenior

The role

Summary

Replit is seeking a Senior Software Engineer for its Trust & Safety team, focusing on building advanced AI-powered detection systems to protect the platform from various cyber threats and abuse. The ideal candidate will develop innovative guardrails for AI-generated code, create sophisticated abuse detection mechanisms, and work at the intersection of AI, security, and platform protection.

What you'll do

AI Security Design: Design and implement LLM guardrails to detect abuse scenarios in AI-generated code and agent interactions

Threat Detection Systems: Build AI-powered detection systems using LLMs to identify malicious patterns, classify threats, and automate response decisions

Abuse Prevention: Develop and operate comprehensive abuse detection systems to identify phishing, cryptomining, account takeover, and financial fraud across millions of daily user actions

Automated Response: Design and implement automated response mechanisms to enforce platform policies without manual intervention

Incident Lifecycle Management: Manage the full abuse response lifecycle including detection, investigation, enforcement, and handling appeals in collaboration with Support and Legal teams

What we look for

Technical

Programming LanguagesProficiency in Python and TypeScript for building detection systems and automation

Data AnalysisAdvanced SQL skills and experience with large-scale data analysis using BigQuery, Snowflake, or similar platforms

Machine LearningExperience building or fine-tuning ML/LLM-based classifiers for security or abuse detection

Education

Computer ScienceBachelor's degree in Computer Science, Cybersecurity, or related technical field preferred

Experience

Security Engineering4+ years of experience in security engineering, anti-abuse, trust & safety, or fraud detection

Attack Pattern AnalysisDemonstrated ability to investigate complex abuse patterns and translate findings into automated defenses

Skills

Required skills

PythonStrong programming skills for building detection systems

TypeScriptProficiency in TypeScript for developing security solutions

SQLAdvanced data analysis and querying skills

LLM SecurityUnderstanding of prompt injection, jailbreaking, and LLM-specific attack vectors

Nice to have

Platform SecurityExperience with user-generated content or compute abuse platforms

Cloud InfrastructureKnowledge of container security, Linux internals, and GCP

Compensation & benefits

Salary

USD 210,000 – 265,000 (annual)

Stock options

Available

Benefits

Competitive Compensation

Competitive salary with equity options

Retirement Planning

401(k) program with 4% company match (US Only)

Healthcare

Comprehensive health, dental, vision, and life insurance

Leave Policies

Paid parental, medical, and caregiver leave

Time Off

Flexible Time Off (FTO) with additional holidays

Wellness Benefits

Monthly wellness stipend and commuter benefits

Interview process

1
Initial Screening — Preliminary review of application and resume
2
Technical Phone Screen — Detailed discussion of technical skills and experience in security engineering
3
Technical Interview — In-depth technical assessment of security and AI detection system design skills
4
Team Interview — Collaborative interview with Trust & Safety team members
5
Final Interview — Meeting with hiring manager to discuss role alignment and team fit