Windows Entitlement + Telemetry Platform [Senior C# / .NET Engineer]

Spark is building a subscription-based driver-development platform centered on proprietary, high-fidelity track content for Assetto Corsa. The member experience is straightforward: JOIN + PAY → DOWNLOAD → AUTHORIZE DEVICE → DRIVE THROUGH CONTENT MANAGER → UPLOAD SESSION DATA Content Manager will remain the simulator-side interface. We are not building a custom launcher. We are seeking one accountable senior product engineer [or a compact two-person team with a clearly identified technical lead] to build the software platform surrounding our track files. PROJECT SCOPE 1. Member web platform - Responsive member account area - Managed authentication - Stripe subscriptions, webhooks and customer portal - Protected track downloads - Training/video content - Basic member activity and administrative tools 2. Entitlement backend - Membership and billing states - Device registration and management - Short-lived signed entitlement leases - Offline grace-period behavior - Package/key management - Renewal and revocation - Audit logging and authenticated APIs 3. Windows access and telemetry software - Windows 10/11 - C# on the current .NET LTS release, currently .NET 10 - Signed installer and updater - Background access service and per-user telemetry agent - Browser-based device authorization - Secure local credential storage - Protected payload handling - Crash and reboot cleanup - Content Manager integration 4. Telemetry and data platform Target data includes: - Spark track, layout and build identifiers - Car and session identifiers - Driving days, hours and sessions - Laps, sectors and lap times - Off-track events - 10–20 Hz brake, throttle, steering, speed and position data - Encrypted offline queue and reliable upload - Compressed lap storage and database summaries Some values will come directly from Assetto Corsa, while others must be derived by Spark or combined with track-specific metadata. The developer must produce a field-availability matrix documenting each source and limitation. 5. Production engineering and handoff - Automated tests - Structured logging and support diagnostics - CI/CD and deployment - Threat model - Operating and recovery documentation - Reproducible builds V1 is intentionally focused: this engagement does not include track-file creation, a visible Spark launcher, mobile apps, racing-platform features, or KUNOS/Steam integration. TECHNICAL REQUIREMENTS - The Windows access and telemetry software must use C# on .NET 10 LTS. ASP.NET Core on the same LTS release is preferred for backend services; alternatives require a clear technical and economic justification. - The software must not modify or inject code into Assetto Corsa. Content Manager may help trigger authorization, but cannot be the only entitlement control. - Every authorized member must receive byte-identical runtime track content so standard Assetto Corsa multiplayer checksums continue to match. - The objective is commercially meaningful membership enforcement and deterrence, not a claim of unbreakable DRM. - Telemetry should be collected only while Spark content is active by default, with clear disclosure, pseudonymous analytics identifiers and secure transport and storage. FIRST TECHNICAL MILESTONE Before the full production build proceeds, the selected developer must implement working software that proves: - Detection of an active Spark track session - Live Assetto Corsa telemetry capture - Local offline queuing and subsequent upload - Active, lapsed, restored and offline-grace entitlement states - Protected-payload handling using a synthetic test payload - Service restart and reboot cleanup - Byte-identical authorized runtime output - A field-by-field telemetry availability matrix This is an implementation milestone, not a separate architecture exercise or unpaid take-home assignment. OWNERSHIP Spark will own all deliverables and intellectual property created under the engagement, including source code, raw telemetry, schemas, labels, processed and derived datasets, aggregates, model features, documentation, accounts, infrastructure, cryptographic keys and build pipelines, subject to member privacy rights and applicable law. Spark code, business information and data may not be reused, disclosed or used to train third-party AI models without written authorization. WHO SHOULD APPLY We are looking for one senior product engineer [or a compact two-person team] with demonstrated experience delivering production software across both Windows and web/cloud environments. You should have relevant experience with: - C# on the current .NET LTS release - Windows services or background applications - Windows installers, application updates and code signing - ASP.NET Core APIs and relational databases - Authentication, entitlement or software-licensing systems - Stripe subscriptions, webhooks and account-status changes - Secure local storage, signed tokens and offline-access rules - Telemetry, streaming data or high-frequency event pipelines - Automated testing, logging, CI/CD and production deployment The strongest candidate does not need previous Assetto Corsa experience, but must be comfortable learning a documented simulator telemetry interface and safely integrating with an existing Windows application. Experience with games, simulators, connected devices or desktop SaaS is helpful. AI-assisted development using tools such as ChatGPT Codex or Claude Code is welcome. The engineer remains accountable for system architecture, security decisions, test coverage, maintainability and release quality. Please do not apply if your experience is limited to ordinary websites, WordPress, game artwork or front-end development. We are also not seeking a large agency. We want direct access to the senior engineer responsible for the work. APPLICATION INSTRUCTIONS Please answer every screening question with specific examples of work you personally completed. Generic or AI-generated answers that do not address the questions will not be considered. Please begin your proposal with SPARK10 to confirm that you reviewed the complete posting and attached project brief.