Remote | Sr. Full-Stack Software Engineer - $50-$100/hour

About the job Remote | Sr. Full-Stack Software Engineer - $50-$100/hour We are sharing a specialised consulting opportunity for experienced Full-Stack Software Engineers with strong expertise across front-end and back-end development, application architecture, debugging, APIs, databases, service integration, and multi-language software engineering to contribute to an advanced AI training and software-evaluation project. Selected professionals will create, solve, review, and validate challenging software-engineering tasks across complete application stacks. The work requires meaningful hands-on experience with both front-end and back-end systems, the ability to navigate unfamiliar repositories, strong debugging skills, and sound judgement when evaluating code for correctness, performance, security, and maintainability. Key Responsibilities Full-Stack Application Development Develop and modify front-end and back-end application components Build user-facing features and supporting services Work across browser applications, APIs, databases, and external integrations Maintain consistency between client-side and server-side behaviour Implement changes that fit existing architecture and coding conventions Front-End Engineering Develop and debug user-facing application features Work with JavaScript, TypeScript, React, or comparable front-end technologies Manage application state and client-side data flows Integrate front-end components with APIs and backend services Diagnose rendering, interaction, and browser-level issues Back-End Engineering Develop APIs, services, and backend application logic Work with technologies such as Python, Java, Node.js, Go, Rust, or comparable languages Design and modify server-side workflows Support authentication, persistence, and service integration Troubleshoot backend failures and data-processing issues API & Service Integration Trace requests across clients, APIs, services, and external systems Diagnose contract mismatches and integration failures Evaluate request and response behaviour Review authentication and authorisation flows Maintain reliable communication between application components Database & Persistence Workflows Work with application data models and persistence layers Analyse interactions between services and databases Troubleshoot data consistency or storage-related issues Evaluate schema or model changes within existing systems Support reliable data access across application workflows Debugging & Root-Cause Analysis Diagnose failures across complex application stacks Investigate application state, API contracts, networking, authentication, and deployment issues Trace execution and data flow across system boundaries Identify underlying causes rather than surface symptoms Develop technically sound fixes Repository Exploration Work effectively inside unfamiliar codebases Understand project architecture, dependencies, and contribution patterns Identify relevant modules and system boundaries quickly Review existing implementation approaches before modifying code Adapt to repository-specific coding and testing practices System Architecture Analyse the architecture of complete software systems Evaluate relationships between front-end, backend, data, and infrastructure layers Identify architectural weaknesses or unnecessary complexity Assess whether proposed changes fit existing design patterns Support maintainable evolution of application systems Multi-Language Engineering Review and modify code written in multiple languages Translate full software implementations from one language into another where required Preserve behaviour and architectural intent during translation Adapt to language-specific tooling and conventions Evaluate implementation trade-offs across language ecosystems Software Testing & Validation Validate changes against expected behaviour Develop or review unit, integration, regression, and end-to-end tests Identify missing test coverage Verify fixes against original failure conditions Reduce regression risk across affected application layers AI-Generated Code Evaluation Review AI-generated solutions for correctness and completeness Evaluate performance and security implications Identify maintainability concerns Assess whether solutions fit repository architecture Provide structured feedback to improve engineering quality Technical Communication & Collaboration Explain technical reasoning clearly Document important implementation decisions Communicate debugging findings and trade-offs Collaborate remotely with engineers and project stakeholders Maintain consistent engineering standards across assigned tasks Ideal Profile Strong professional experience developing production full-stack applications Meaningful hands-on experience with both front-end and back-end engineering Production experience with multiple programming languages Strong knowledge of browser applications and client-side development Strong understanding of APIs and service integration Experience with application state and data flow Strong database and persistence-layer knowledge Experience contributing to complete software-system architecture Ability to work effectively in unfamiliar repositories Strong debugging and technical problem-solving skills Experience with Python, JavaScript, TypeScript, Java, Node.js, Rust, Go, or comparable languages is highly relevant React experience is valuable Ability to evaluate code for correctness, security, performance, and maintainability Experience translating software implementations between programming languages is advantageous No prior AI-training or model-evaluation experience is required Engagement Details Part-time independent contractor engagement Fully remote and open globally Expected commitment: approximately 15 hours per week Flexible schedule; contributors may choose their working hours and days, including weekends, provided there is regular activity Displayed compensation range: $50-$100/hour Actual compensation structure is output-based, with payment made per task that meets project specifications Task completion time may vary depending on individual experience and workflow Minimum weekly submission requirements apply; the source does not specify the exact number of required tasks Work will involve front-end and back-end development, APIs, databases, application architecture, debugging, code review, multi-language engineering, and AI-generated solution evaluation Strong hands-on full-stack experience is central to this engagement Roles are typically filled within approximately 48 hours Selected experts are expected to begin initial tasks within approximately 24-48 hours after onboarding Project scope, repositories, languages, technical tasks, and evaluation standards may evolve depending on project requirements Work must be completed without using confidential or proprietary information belonging to any employer, client, private repository, software organisation, or other third party About the Platform This opportunity is available through 24-MAG LLC. 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