Security Engineer | Square Global Negotiation Guide

Negotiation DNA: Equity-Heavy (Block RSUs) + Bonus | AI-Powered Commerce Tools | $45B+ Market Cap | 56M+ Sellers | COMMERCE AI PREMIUM

Region	Base Salary	Stock (RSU/4yr)	Bonus	Total Comp
San Francisco	$178K–$228K	$165K–$292K	12–18%	$245K–$342K
New York	$178K–$228K	$165K–$292K	12–18%	$245K–$342K
Remote US	$168K–$215K	$155K–$272K	12–18%	$228K–$322K

Negotiation DNA

Square Security Engineers protect the commerce infrastructure processing billions of transactions for 56M+ sellers — owning application security, infrastructure security, fraud prevention systems, and compliance frameworks across Square's payment platform. At the IC2-IC4 level within Block's $45B+ ecosystem, you defend one of the largest financial attack surfaces in fintech, ensuring PCI-DSS compliance, SOC 2 attestation, and protection against increasingly sophisticated payment fraud. With Square's 2026 AI-powered commerce initiative, Security Engineers now secure the AI model pipeline — protecting ML models from adversarial attacks, ensuring AI-driven recommendations cannot be manipulated, and preventing data poisoning of training datasets. Block RSUs with NYSE liquidity reward security engineers who protect the financial trust of 56M+ sellers. [Source: Square SecEng Comp 2025-2026]

Level Mapping: Square SecEng (IC2-IC4) = Stripe SecEng = Shopify SecEng = Toast SecEng = Google L3-L5 Security Commerce

🏗️ Square AI-Powered Commerce Tools Lever

As a Security Engineer during Square's AI commerce transformation, you secure the entire AI pipeline — from training data integrity to model serving security to output validation. You protect against adversarial ML attacks that could manipulate pricing recommendations, poison demand forecasting models, or exploit AI-driven automation to commit fraud at scale.

AI security for commerce is a new frontier. Your work ensures that AI-powered tools are trustworthy, that model outputs cannot be manipulated, and that seller data feeding ML models is protected throughout the entire pipeline.

Global Levers

1. AI Commerce Security: "I secure the AI pipeline powering intelligent tools for 56M+ sellers — protecting against adversarial ML attacks, data poisoning, and model manipulation. AI security for commerce is a new frontier requiring specialized expertise that commands premium compensation."
2. Financial Attack Surface Protection: "I defend one of the largest financial attack surfaces in fintech — billions of transactions across 56M+ sellers. PCI-DSS compliance, fraud prevention, and payment security at this scale demand premium security engineer compensation."
3. Stripe/Shopify SecEng Competition: "Stripe and Shopify offer $330K+ TC for Security Engineers protecting AI commerce infrastructure. Square must match competitive compensation to retain security engineers who can defend both financial systems and AI pipelines."
4. AI Model Security Pioneer: "I'm pioneering security for AI-powered commerce — protecting ML models from adversarial manipulation, securing training data pipelines, and validating model outputs. Security engineers with AI/ML security expertise are exceptionally rare in fintech."

Negotiate Up Strategy: "I'm targeting $222K base and $282K RSUs over 4 years with 18% performance bonus for this Security Engineer role. I secure the AI pipeline powering commerce tools for 56M+ sellers — protecting against adversarial ML attacks, data poisoning, and model manipulation across Square's payment infrastructure. I have competing offers from [Stripe at $330K TC / Shopify at $318K TC / Toast at $305K TC]. Security Engineers who can protect both financial systems and AI pipelines are the rarest security talent in fintech." Accept at $198K+ base and $238K+ RSUs.

Evidence & Sources

• [Square AI Commerce Tools — 2026 Strategic Initiative]
• [Square SecEng Comp — Levels.fyi 2025-2026]
• [Block Inc $45B+ Market Cap — NYSE: SQ]
• [Square vs Stripe/Shopify — Security Engineer Competition]