Apple is looking for a senior software engineer to build the next generation of inference routing for Private Cloud Compute, the backbone of Siri AI and Apple Intelligence. You'll design distributed systems that direct inference requests across a global fleet of inference servers, balancing latency, availability, and compute efficiency while preserving PCC's privacy guarantees. Your work will directly shape how reliably and efficiently Apple delivers cloud inference at scale.
You'll join iCloud Platform Engineering team. We build the server stack behind Push Notifications, iMessage, FaceTime, iCloud, iCloud Private Relay and Private Cloud Compute. Our internet scale distributed systems deliver real-time experiences with very low latency and very high availability. They reach hundreds of millions of users across a billion devices worldwide and help them connect and share their lives securely and privately. Our work spans identity, messaging, queueing, presence, routing, relays, developer APIs and much more. We're a small, highly collaborative team with a large impact.
Description
Routing LLM inference at Apple's scale requires systems that adapt to changing demand, available capacity, and failures while maintaining low latency and high utilization. PCC adds a fundamental architectural requirement: request content remains encrypted outside trusted compute nodes. You'll develop routing and scheduling strategies within this privacy model, working with inference and security teams to evaluate techniques such as cache aware request placement and prefill/decode disaggregation.
You'll design system architectures, specify custom network protocols and write high performance code. You'll also build scaling strategies for services used by hundreds of millions of people. Our team is small and highly visible, so your chances to make an impact are wide open. If you take opportunities like that and run with them, you'll enjoy working here.
You'll own technical decisions from early design through production, using benchmarks and operational evidence to evaluate tradeoffs. You'll work closely with model serving, infrastructure, security, and SRE engineers to turn new inference requirements into reliable routing capabilities.
Minimum qualifications
3+ years of professional experience designing, building and operating large distributed systems in production
Server development in Java, C/C++, C#, Go or Swift
Knowledge of LLM inference serving, including inference request routing, KV-cache placement and reuse (e.g., prefix-aware routing), prefill/decode disaggregation, and the tradeoffs between latency, throughput and accelerator use
Experience with network protocols, application level networking and client-server architectures, including request routing, load balancing or scheduling at scale
Experience benchmarking, debugging and tuning the performance of distributed systems, plus knowledge of Unix system internals
Experience with cloud deployment and observability technologies such as Kubernetes
Bachelor's degree in an engineering related field or equivalent experience
Preferred qualifications
Experience building LLM inference serving or routing systems such as llm-d, NVIDIA Dynamo, vLLM, SGLang or similar
Familiarity with KV cache aware routing, prefix caching, prefill/decode disaggregation and accelerator capacity placement
Experience with TLS, X.509 certificate evaluation or other secure protocols, and awareness of recent developments in standard protocols
Understanding of cryptographic protocols, encryption, key management and privacy-preserving system design (e.g., Oblivious HTTP, remote attestation)
Experience leading a substantial engineering project from design through production, resolving technical tradeoffs and coordinating across teams.
Ability to explain technical tradeoffs, collaborate across engineering teams, and make progress on problems with incomplete requirements.
Pay & benefits
At Apple, base pay is one part of our total compensation package and is determined within a range. This provides the opportunity to progress as you grow and develop within a role. The base pay range for this role is between $150,400 and $277,600, and your base pay will depend on your skills, qualifications, experience, and location.Apple employees also have the opportunity to become an Apple shareholder through participation in Apple’s discretionary employee stock programs. Apple employees are eligible for discretionary restricted stock unit awards, and can purchase Apple stock at a discount if voluntarily participating in Apple’s Employee Stock Purchase Plan. You’ll also receive benefits including: Comprehensive medical and dental coverage, retirement benefits, a range of discounted products and free services, and for formal education related to advancing your career at Apple, reimbursement for certain educational expenses — including tuition. Additionally, this role might be eligible for discretionary bonuses or commission payments as well as relocation. Learn more about Apple Benefits
Note: Apple benefit, compensation and employee stock programs are subject to eligibility requirements and other terms of the applicable plan or program.