Principal Software Engineer – AMER Payments

Trustly

. Write and merge code on the critical path every week, including reference implementations, contract tests, and the hardest fixes .

Posted 11/2/2026full-timeSan Francisco • California • United StatesLead💰 $260,000 - $390,000 per yearWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates extensive experience in software engineering with a focus on designing and operating payment and banking systems at scale. Capable of leading technical direction and managing cross-domain changes while ensuring robust contract testing and API specifications.

Highest-signal resume keywords

15+ Years Software Engineering ExperienceDistributed Systems ExpertisePayment System Design and OperationTechnical Direction SettingCross-Domain Incident Response

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

Production Code WritingContract TestingAPI Specification ManagementLoad TestingFailure HandlingConcurrency ManagementIdempotencyConsistencyAI in EngineeringTechnical Writing

Soft Skills

Product JudgmentLeadershipCollaboration

Tools & Technologies

CI/CDACHRTPFedNowOpen Banking

Industry Keywords

PaymentsBankingLedger SystemsCross-Domain ChangesEscalation Rotation

Tech Stack

Tools & technologies

Distributed Systems

About the role

Key responsibilities & impact

Write and merge code on the critical path every week, including reference implementations, contract tests, and the hardest fixes
Own contracts between payments, bank connectivity, and risk as versioned repository specifications
Maintain contract tests in CI that fail the build when a contract breaks
Build the first version of difficult cross-domain changes and hand them to the owning team
Own the global API specification with engineers responsible for merchant-facing APIs
Lead the technical response to P0 or P1 incidents crossing domains as part of the escalation rotation
Run peak-event readiness through load tests, failure drills, and capacity calls
Lead the US Platform squad by setting platform priorities and contracts across payments, bank connectivity, and infrastructure
Weigh platform priorities against business squad needs with program support from Core Payments TPMs

Requirements

What you’ll need

Typically 15+ years in software engineering
Principal-level scope across multiple teams
Still writing production code
Experience designing, building, and operating payment, banking, or ledger systems at scale
Record of setting technical direction through code and clear writing
Product judgment to make platform trade-offs with business and product leaders
Deep distributed systems expertise: consistency, idempotency, concurrency, and failure handling
Practical, current use of AI in engineering, with clear judgment on its limits in regulated systems
Experience with ACH, RTP, FedNow, or open banking is nice to have
Must be based out of the San Francisco office and be in the office Tuesday through Thursday
Legal authorization to work in the country where the job is located
Visa sponsorship eligibility is addressed in the application

Benefits

Comp & perks

Flexible paid time off & generous PTO accrual plans
Comprehensive medical, dental, vision, and other insurances
FSA & HSA plans for medical and dependent care
Home office set-up allowance
Internet stipend
Retirement plan match for 401k and RRSP
Gender-neutral paid parental leave
Equity
Bonus