Full Stack Developers in Springboot, FastAPI, NodeJS and Angular 

Spring Boot Developer: About the Role We are seeking an experienced Freelance Spring Boot Developer to join our team on a contract basis. The ideal candidate has hands-on experience developing Java-based extensions for ThingsBoard loT platform and a strong command of the Maven build ecosystem. Angular development experience is a plus and may be required for certain assignments. Key Responsibilities . Design, develop, and maintain Spring Boot microservices and RESTful APIs. . Build and extend ThingsBoard platform capabilities through custom Java-based rule engine nodes, transport handlers, and service integrations. . Develop and maintain custom ThingsBoard widgets. . Configure and manage Maven build lifecycles, dependency management, and multi- module project structures. . Write unit and integration tests to ensure code quality and reliability. . Participate in code reviews and contribute to architectural decisions. . Document technical designs, APIs, and integration patterns. . (If applicable) Develop and maintain Angular-based front-end components that integrate with Spring Boot backends and ThingsBoard APIs. FastAPI Backend Developer: About the Role We are seeking an experienced Freelance FastAPI Backend Developer to join our team on a contract basis. The ideal candidate has hands-on experience building Python-based backend services that run on embedded edge devices, interface with physical peripherals, and communicate with other services via Unix Domain Sockets (UDS). A strong command of the Dependency Injection (DI) design pattern is essential. Key Responsibilities . Design, develop, and maintain FastAPI backend services targeting embedded edge device environments. . Implement clean, testable code using the Dependency Injection (DI) design pattern throughout the application layer. . Interface with physical peripherals (GPIO, serial, CAN bus, I2C, SPI, etc.) through well- defined service abstractions. . Implement Unix Domain Socket (UDS) communication channels for efficient, low- latency inter-process communication between backend services and peripheral daemons. . Design and expose RESTful and/or async APIs for intra-device and cross-service communication. . Write unit and integration tests to ensure code quality and hardware-in-the-loop reliability. . Participate in code reviews and contribute to architectural decisions. . Document technical designs, APIs, peripheral interfaces, and integration patterns. Node.js Developer: About the Role: We are seeking an experienced Freelance Node.js Developer to join our team on a contract basis. The ideal candidate has hands-on experience building custom Node-RED nodes and developing lightweight Node.js applications optimized for resource-constrained embedded devices. A background in loT edge computing and familiarity with low-level hardware interfaces is highly desirable. Key Responsibilities: . Design, develop, and publish custom Node-RED nodes that extend platform capabilities for loT and edge use cases. . Build and optimize Node.js applications for constrained embedded environments (limited CPU, RAM, and storage). . Integrate with hardware peripherals via serial (UART), 12C, SPI, GPIO, and other low- level interfaces from Node.js. . Develop MQTT-based messaging pipelines and manage broker connectivity, QoS levels, and message persistence. . Profile and optimize memory and CPU usage to meet the constraints of embedded targets (e.g., Raspberry Pi, Beagle Bone, OpenWrt devices). . Write unit and integration tests to ensure node reliability and application stability under constrained conditions. . Participate in code reviews and contribute to architectural and design decisions. . Document custom node APIs, configuration schemas, and deployment procedures.