Site Reliability Engineer (SRE) / Mobile IOS /observabilité (IT) / Freelance
Free-Work · Paris, Île-de-France, France
- On site
- Full-time
- $100,000 / year
- Paris, Île-de-France, France
Job highlights
- Ensure mobile and backend system reliability and performance.
- Implement and monitor critical user journey SLIs/SLOs.
- Enhance full-stack observability using Splunk, Grafana, CloudWatch.
- Manage incidents, on-call rotations, and coordinate remediation.
- Automate deployments, manage scalability, and secure mobile-backend.
About the role
Site Reliability Engineer (SRE) - Mobile Focus
CONTEXT
Our client is a significant e-commerce company operating high-traffic mobile (iOS and Android) and web applications. To meet increasing demands for service quality and scale, they are expanding their SRE team to ensure end-to-end reliability of their mobile and backend ecosystems.MISSION OF THE PROVIDER
**Reliability, Availability & Performance**- Define and monitor Service Level Indicators (SLI) and Service Level Objectives (SLO) for critical mobile user journeys (login, data loading, payment, push notifications).
- Ensure high availability of backend APIs consumed by the mobile application, collaborating with backend teams.
- Contribute to reducing API response times (target < 100 ms at the BFF level, down from ~3 seconds).
- Implement edge caching and optimize mobile network performance.
- Deploy full-stack observability (backend + mobile) using Splunk, Grafana/Prometheus, CloudWatch (AWS), and APIGEE.
- Correlate technical data with user sentiment (App Store/Google Play reviews).
- Verify production monitoring coverage and identify blind spots.
- Participate in on-call rotations.
- Detect, qualify, and dispatch incidents to the appropriate teams.
- Coordinate remediation actions and write blameless post-mortems.
- Monitor production status and response times.
- Implement progressive deployment strategies (canary, blue/green) and automated rollbacks.
- Utilize feature flags to manage risks on the mobile side.
- Synchronize backend deployments with mobile releases.
- Anticipate and handle traffic peaks (marketing campaigns, mass push notifications, business events).
- Implement dynamic autoscaling for APIs and optimize cloud costs.
- Secure mobile/backend communication (JWT token rotation, rate limiting, secret and API key management).
- Protect APIs against abuse and abnormal traffic.
- Work closely with iOS/Android developers, backend teams (BFF, API), product teams, and customer support.
- Contribute to architectural decisions and integrate reliability from the design phase (reliability by design).
- Produce and facilitate SLO/SLI/SLA dashboards, post-mortem analyses, and a reliability roadmap.
- Participate in product rituals and weekly analysis of user feedback.
REQUIRED PROFILE
**Technical Skills Required**- Solid experience in SRE or MCO for mobile (real iOS/Android) and web application environments.
- Proficiency with observability tools: Splunk, Grafana/Prometheus, CloudWatch (AWS).
- Good knowledge of BFF/REST API architectures, particularly in NodeJS/GraphQL environments.
- Understanding of frontend web (VueJS, NestJS) and mobile (Android/Kotlin, Swift) stacks.
- Experience with JS web servers (e.g., Nginx).
- Knowledge of SLI/SLO/SLA concepts and ability to build and analyze reliability KPIs.
Key skills/competency
- Site Reliability Engineering (SRE)
- Mobile Observability
- API Performance
- Incident Management
- On-Call Rotation
- Automated Deployments
- Scalability
- Cloud Optimization
- Security
- Reliability Engineering
Skills & topics
- Site Reliability Engineering
- SRE
- Mobile SRE
- iOS
- Android
- Observability
- Splunk
- Grafana
- Prometheus
- CloudWatch
- AWS
- APIGEE
- API Performance
- BFF
- NodeJS
- GraphQL
- VueJS
- NestJS
- Kotlin
- Swift
- Nginx
- SLI
- SLO
- SLA
- Incident Management
- On-Call
- Canary Deployment
- Blue/Green Deployment
- Feature Flags
How to get hired
- Tailor your resume: Highlight SRE experience, mobile application reliability, and observability tools like Splunk, Grafana, and CloudWatch.
- Showcase API expertise: Detail your experience with BFF/REST APIs, NodeJS, GraphQL, and performance optimization.
- Demonstrate mobile knowledge: Emphasize your understanding of iOS/Android stacks and mobile-specific SRE challenges.
- Prepare for technical questions: Be ready to discuss SLI/SLO definition, incident management, and deployment strategies.
- Understand the culture: Research Free-Work's focus on e-commerce, mobile, and reliability by design.
Technical preparation
Master Splunk, Grafana, Prometheus, CloudWatch configurations.,Practice defining and measuring SLI/SLO for mobile journeys.,Build and test automated deployment and rollback strategies.,Simulate API performance tuning scenarios, e.g., caching.
Behavioral questions
Describe a complex incident you managed.,How do you prioritize reliability improvements?,Explain a time you collaborated across teams.,How do you handle production issues under pressure?
Frequently asked questions
- What is the primary focus of this Site Reliability Engineer role at Free-Work?
- The primary focus of this Site Reliability Engineer role at Free-Work is to ensure the end-to-end reliability, availability, and performance of high-traffic mobile (iOS and Android) and web applications, with a strong emphasis on mobile observability and API performance.
- What are the key observability tools mentioned for this Free-Work SRE position?
- The key observability tools mentioned for this Free-Work SRE position include Splunk, Grafana/Prometheus, CloudWatch (AWS), and APIGEE, covering full-stack monitoring from backend to mobile experience.
- What is the target response time for APIs in this role?
- The target response time for APIs in this role is less than 100 milliseconds at the BFF level, aiming to significantly reduce the current average of approximately 3 seconds.
- Does this Site Reliability Engineer role involve on-call duties?
- Yes, this Site Reliability Engineer role involves participating in on-call rotations to manage and respond to production incidents.
- What level of experience is expected for this SRE position at Free-Work?
- Solid experience in SRE or MCO (Maintenance in Operational Conditions) for mobile and web applications is expected, along with specific technical skills in observability tools and API architectures.
- What kind of mobile technologies are relevant for this role?
- Relevant mobile technologies for this role include the iOS and Android stacks, with specific mention of Swift for iOS and Kotlin for Android.
- How does this role contribute to user experience?
- This role contributes to user experience by correlating technical performance data with user sentiment from app store reviews and ensuring the reliability of critical mobile user journeys.
- What are the expected collaboration dynamics for the SRE at Free-Work?
- The SRE is expected to collaborate closely with iOS/Android developers, backend teams, product teams, and customer support, integrating reliability from the design phase.