Discover Golang Projects on Upwork with Vollna

Kind of startup company, seeking a new candidate with simple test project, then, move forward to long term opportunity.

Skills:

Golang (Go), REST APIs, SQL databases

Backend architecture and microservices

API development, concurrency, and performance optimization

OpenTelemetry (OTEL), monitoring, and observability

Database transactions, error handling, and high-load systems

Git, automated testing, and production deployment

# Senior Ruby on Rails Engineer for Production Applications

We’re looking for an experienced Ruby on Rails engineer to build and support production applications at enterprise scale. You’ll own features from design through release, working closely with product, QA, and platform teams.

## What you’ll do

- Design, build, test, and maintain Rails features and backend services.
- Design and integrate RESTful APIs.
- Model relational data and improve ActiveRecord and SQL query performance.
- Troubleshoot production issues and help keep applications reliable.
- Participate in code reviews and CI/CD delivery workflows.
- Collaborate across the full product delivery cycle.

## Required qualifications

- Strong, hands-on Ruby on Rails experience supporting production applications.
- Solid Ruby fundamentals and familiarity with Rails conventions.
- Experience designing, developing, and integrating REST APIs.
- Practical relational database experience, including schema design, ActiveRecord, and SQL tuning.
- Automated testing experience with RSpec or Minitest.
- Comfortable with Git, code review, and CI/CD workflows.
- Bachelor’s degree in Computer Science or equivalent practical experience.

## Nice to have

Experience with one or more of the following:

- Go (Golang) backend services or Java enterprise and microservices development.
- Sidekiq or Resque.
- Docker or Kubernetes.
- AWS, GCP, or Azure.
- Redis or Elasticsearch.

Location: Austin Texas

## To apply

Please include:

1. A brief summary of your production Rails experience, including the types of applications you’ve supported.
2. One example of a Rails feature, API, or performance issue you handled, and your role in the work.
3. The testing tools and deployment workflows you’ve used.
4. Any experience with the nice-to-have technologies listed above.

I’m building a brand-new backend in Go to power an online store / booking platform and I’d like an experienced Golang developer to own the API from the ground up. The service must expose clean REST (or GraphQL, if you prefer) endpoints that cover three core areas:

• User accounts with secure sign-up, sign-in, password reset and JWT/OAuth2 session handling
• A catalogue of products or services with searchable listings, real-time availability and basic admin endpoints
• Order / booking flow that accepts online payments (Stripe or PayPal SDKs are fine) and keeps audit-ready records

PostgreSQL or MySQL will sit underneath, accessed through idiomatic Go (GORM, sqlx or raw database/sql—your call). The code should compile cleanly with Go modules, follow standard project layout, and include Swagger / OpenAPI docs so the front-end team can plug in immediately.

Acceptance criteria
– All endpoints return correct data and error codes
– Unit & integration tests pass in CI
– Docker image builds and runs the service with a single command
– README explains setup, env vars and migration steps

Ship the repository (Git) plus any migration files, container scripts and generated docs—once it runs on my DigitalOcean droplet, we’re done.

Skills: PHP, Java, JavaScript, Golang, MySQL, PostgreSQL, RESTful, Docker, Flutter, API Development

Hi Roman,

I hope you are well.

I am launching a long-term, sustainable Matchmaking/Marriage Website tailored for the Middle East, and I am looking for a strong Tech Partner (CTO) rather than just a one-time freelancer.

My Proposal for a Long-Term Partnership:
1. Initial Build: A fixed budget of $6,650 (approx. 25,000 SAR) to design, develop, and launch the MVP (including secure profiles, advanced matching algorithm, secure internal chat, and admin moderation panel).
2. Project Timeline: The complete MVP must be fully developed, tested, and ready for deployment within a timeframe of 3 to 4 weeks.
3. Long-Term Partnership: In exchange for managing, maintaining, and updating the platform continuously after the launch, I am offering a [10% to 20%] share of the monthly net revenue/subscriptions.

This hybrid model ensures you are a true partner in the success of this platform, with a recurring income stream as we scale together.

Please let me know if this model and timeline work for you so we can arrange a brief discussion about the project details.

Best regards,
Motlaq
Saudi Arabia
Madina

Looking for multiple people to work onsite in indore, India. If you’re interested in learning more, please message me. I have Devops roles, telemetry, go, python and many more. This is a full-time Gig and will continuously have the opportunity to grow and earn more.

We’re looking for experienced software engineers to contribute to blockchain and financial infrastructure projects.

We’re interested in engineers with experience in backend development, APIs, payment systems, transaction processing, smart contracts, or blockchain protocol development.

Previous professional experience in blockchain, digital assets, stablecoins, or financial systems is preferred.

Multiple roles are available. Further project details will be shared in chat.

About Us
We’re a software agency that designs and builds web apps and SaaS products for clients around the world. We’re looking for an experienced software professional to represent our technical team on client video calls.

WHAT YOU WILL DO

Join scheduled Google Meet calls with our existing clients
Present project progress and explain technical details in plain, clear language
Answer client questions using the briefing materials we prepare for you
Note client feedback, concerns, and requests during each call
Send us a short written summary after every call, including feedback and action items

WHAT YOU WILL NOT DO

No coding or hands-on development
No sales, cold outreach, or finding new clients

HOW IT WORKS

Before the call: We send you the project status, the agenda, and key talking points.
During the call: You lead the technical discussion and answer questions with confidence.
After the call: You send us a summary within a few hours.

If a client asks something outside the briefing, simply let them know the team will follow up, and pass the question to us.

REQUIREMENTS

7+ years in software engineering, solution architecture, technical leadership, or IT consulting
Fluent spoken English with a clear, professional communication style
Solid understanding of web development and SaaS products (front end, back end, APIs, cloud hosting, release cycles)
Ability to explain technical topics to non-technical people
Reliable webcam, stable internet connection, and a quiet space for calls
Punctual, well-prepared, and dependable

NICE TO HAVE

Experience as a tech lead, architect, or consultant
Direct experience managing client relationships or stakeholder meetings
Master’s degree or PhD in Computer Science, Software Engineering, or a related field
Familiarity with project tools such as Jira, Trello, or Notion

DETAILS

Fully remote
Calls are scheduled in advance; no fixed hours or minimum commitment
Most calls take place during US business hours
Long-term, ongoing work for the right person

TO APPLY
Please answer the screening questions below.

Senior Cosmos SDK / Layer‑1 Blockchain Engineer (Nexus AI Foundation)
About the Project:
We are building , a sovereign Layer‑1 blockchain designed for deterministic AI agent execution, sovereign data capsules, and multi‑agent coordination. We are looking for an elite Cosmos SDK engineer with deep protocol-level experience to architect our core chain and modules.

(Note: This is a protocol-level L1 role. Experience with smart contracts/EVM dApps alone is not a match.)

Key Responsibilities:

Core L1 Chain: Build and configure a sovereign Cosmos SDK chain (staking, governance, bank, genutil, fee modules, fixed supply, custom denom unexus).

Custom Modules: Implement the Agent VM, Data Capsule Module, Coordination Mesh, and fee/burn engines with proper genesis states and parameters.

Genesis Engineering: Build genesis.json, configure token allocations (founders, team, investors, ecosystem, validators), and set initial parameters.

Testnet & Mainnet Launch: Setup validator nodes, keyrings, sentry nodes, and network configuration.

Requirements:

3+ years of Cosmos SDK development experience

5+ years of Go (Golang) experience

Proven track record of launching sovereign chains

Experience writing custom Cosmos modules

Deep understanding of Tendermint/CometBFT consensus and genesis engineering

Strong background in cryptography and distributed systems

Bonus Skills: CosmWasm, IBC, ZK systems

I'm looking for an experienced AI developer to help troubleshoot a small issue with an existing OpenAI API integration in my Node.js application.

The API is already connected, but I'm having trouble getting consistent responses and properly handling the output.

What I need:

Review the existing OpenAI API integration.

Identify and fix the response-handling issue.

Test the integration to ensure it's working correctly.

This should be a quick task for someone familiar with OpenAI APIs, Node.js, and LLM integrations.

Budget: $15 Fixed Price

Timeline: Within 24 hours

Please apply if you've worked with similar AI integrations and can help resolve this quickly.

We are building a multi-tenant SaaS platform with a mobile-first web app, an iOS mobile app, location-based features, subscription billing, a media delivery service, healthcare data integrations and an AI assistant. We have a product spec and an early prototype. We need an engineer, or a small team led by one engineer, to take it through four fixed-price milestones. We care about a working demo at each milestone, not just code we cannot evaluate.

PROJECT SCOPE

Milestone 1: Foundations and Architecture

Review the existing prototype and codebase and give us a written assessment: what exists, what is missing, and the recommended path forward.
Set up dev, staging and production on AWS (ECS, Fargate, EC2, VPC, IAM) with Pulumi for infrastructure as code.
Build CI/CD with GitHub, Jenkins or GoCD, and AWS CodePipeline and CodeDeploy.
Create the data layer on PostgreSQL (Aurora) and Redis, with MySQL, MongoDB and DynamoDB where each fits.
Build authentication: magic-link login, JWT, API keys, role-based permissions, admin MFA and rate limiting.

Milestone 2: Core Product

Web app: Next.js (App Router), React, TypeScript and Tailwind CSS, plus an Angular admin dashboard.
Mobile app: Flutter (Dart) or React Native for iOS, with push notifications and App Store submission.
Backend services: Go 1.20+ (Gin, Gorm, goroutines, channels, gRPC) and a Node.js/NestJS API layer with Prisma.
Real-time features: presence and live updates with Elixir and Phoenix channels.
Location features: interactive map with Leaflet and OpenStreetMap, plus GPS proximity detection.
Admin tools: a content back-office that needs no code changes.

Milestone 3: Payments, Contracts and Integrations

Payments: subscriptions and one-time purchases with Stripe, Paddle and PayPal behind one internal payment interface, including webhooks with signature verification, idempotency, refunds and failure handling.
E-signing: Oneflow or Scrive integration for electronic contracts, with the architecture ready for BankID and ID06.
Healthcare: EHR integration using FHIR and HL7 standards.
Background work: message queues and asynchronous jobs.
Legacy and third-party: a legacy PHP module to integrate with, plus third-party APIs.
Media: a streaming service (HLS and DASH, transcoding) running on a Linux VPS. A Rust worker for the transcoding path is welcome.

Milestone 4: AI, Hardening and Handover

AI service in Python with FastAPI: LLM integration, RAG, and agents using LangChain, LangGraph or the OpenAI Agents SDK. Content ingestion uses Python-Goose, and early workflow prototypes may be done in Stack AI.
Observability: Prometheus, Grafana and Datadog.
Orchestration: Docker and Docker Compose for local and staging, Kubernetes for production (EKS on AWS, GKE and Compute Engine on GCP).
Security and compliance: GDPR workflows, encryption at rest and in transit, EU hosting (AWS Stockholm), audit logs and anti-scraping controls.
Testing: Jest, Playwright and Go tests on core business logic.
Handover: source code in our GitHub, documentation and a walkthrough call.

TECHNOLOGY REFERENCE
Languages: Go, Python, JavaScript, TypeScript, Dart, Elixir, Rust, PHP.
Frontend: React, Next.js, Angular, Tailwind CSS, Leaflet/OpenStreetMap.
Mobile: Flutter, React Native, iOS, push notifications.
Backend: Gin, Gorm, FastAPI, Node.js, NestJS, Prisma, Phoenix, gRPC, REST.
Databases: PostgreSQL, Aurora, MySQL, MongoDB, DynamoDB, Redis.
Cloud and DevOps: AWS (ECS, Fargate, EKS, EC2, VPC, IAM, CodeDeploy, CodePipeline), GCP (GKE, Compute Engine), Docker, Docker Compose, Kubernetes, Pulumi, Jenkins, GoCD, GitHub, Linux.
Payments and contracts: Stripe, Paddle, PayPal, Oneflow, Scrive, BankID, ID06.
AI: LLMs, RAG, AI agents, LangChain, LangGraph, OpenAI Agents SDK, Stack AI, Python-Goose.
Observability: Prometheus, Grafana, Datadog.
Testing: Jest, Playwright.
Media and health: HLS, DASH, FHIR, HL7.

WHAT WE NEED FROM YOU

A short description of a past project that combined at least two of: accounts, maps, payments, real-time features or AI.
Which of the technologies above you have used in production, which you have not, and how you would close the gaps.
Your fixed price and timeline per milestone, your availability and your time zone.
Links to a GitHub profile or live work.

We are seeking an experienced Platform Engineer or Software Development Lifecycle (SDLC) Tooling Engineer for a hands-on development and integration project focused on KoineDSL, a tool-agnostic Domain-Specific Language (DSL) for Internal Developer Platforms (IDPs). The goal is to enable platform engineers to define and manage workflows independently of the underlying tools, vendors, and implementations, creating a common language for expressing intent across the SDLC ecosystem.

We are not looking for someone who simply uses or configures CI/CD tools. We need an engineer who understands how these systems work internally and has experience building, extending, or contributing to platform engineering or SDLC tooling. Experience contributing to open-source projects such as Jenkins, Spinnaker, Tekton, Argo, FluxCD, or comparable systems is highly desirable. Only applicantts with serious previous expereince will be considered. We already know what AI agents can do with it. We seek a level of understanding that comes with expereince.

### About KoineDSL

KoineDSL is a tool-agnostic Domain-Specific Language (DSL) for Internal Developer Platforms (IDPs), designed to let platform engineers express workflow intent independently of the tools, vendors, and infrastructure responsible for execution.

Traditional IDPs rely on tool-specific configurations, integrations, and custom automation to coordinate workflows across the Software Development Lifecycle (SDLC). This creates tight coupling between what a platform engineer intends to accomplish and how individual tools implement that intent.

KoineDSL takes a different approach.

By providing a common language for declaring workflow expectations, KoineDSL separates what should happen from how it happens. Platform engineers can define expected outcomes, dependencies, conditions, and responses to unexpected behavior without embedding vendor-specific implementation details into their workflow definitions.

This enables organizations to build IDPs around their own processes rather than adapting their processes to the limitations of individual tools. Workflows remain portable, extensible, and understandable across heterogeneous SDLC environments.

KoineDSL works alongside several supporting components:

Koine: The underlying language model for expressing and resolving workflow intent.

Conduit: A tool-agnostic, proleptic event orchestration engine that interprets declared expectations, correlates real-time events and tool state, and coordinates actions across the SDLC ecosystem.

Plugin Architecture: An extensible integration layer connecting KoineDSL expressions to the underlying SDLC tools, enabling vendor-specific operations without introducing vendor dependencies into the language.

Iron Monkey: A companion SDLC event simulator used to validate workflow definitions against expected, unexpected, and out-of-order events.

Together, these components enable platform engineers to define workflows once, connect them to their existing tools, and validate their behavior under real-world conditions.

The primary implementation language is Go (Golang).

### Scope of Work
The selected engineer will receive access to the necessary source code, libraries, and project documentation.

The engagement includes:
1. Local Environment Setup
- Build, configure, and successfully run Conduit locally.
- Build, configure, and successfully run Iron Monkey locally.
- Demonstrate a working local environment.
2. Koine DSL Development
- Create or extend custom Koine expressions to describe an SDLC workflow.
- Configure Conduit to observe and evaluate the declared workflow expectations.
- Validate the workflow using Iron Monkey.
3. Plugin Integration and Development
- Use the existing Conduit plugin library to integrate the necessary SDLC tool capabilities.
- Extend or implement plugins where necessary to close the operational feedback loop.
- Demonstrate how internal tool state and external workflow events are correlated to detect unexpected behavior and support corrective action.
4. End-to-End Demonstration
- Execute the workflow using Conduit and Iron Monkey.
- Demonstrate expected execution and at least one unexpected condition.
- Show how Conduit detects the deviation and initiates the appropriate action through its plugin architecture.

### Deliverables and Acceptance Criteria
This is a working-code engagement, not a research, consulting, or architectural assessment project.

The expected deliverables are:
- A working local Conduit and Iron Monkey implementation.
- Functional Koine DSL additions or extensions.
- Any necessary plugin additions or modifications.
- A live demonstration of the complete workflow.
- A clean Git diff containing all source code changes.
- Documentation sufficient to reproduce the demonstration.

Final acceptance requires that I can reproduce the demonstrated functionality in my own local environment using the delivered changes.

A successful demonstration on the contractor's machine alone does not constitute project completion.

### Required Qualifications
- Strong Go development experience.
- Direct experience building, maintaining, or contributing code to SDLC or platform engineering tools.
- Experience with CI/CD orchestration, workflow engines, or event-driven systems.
- Experience developing integrations, plugins, or extensions for existing software platforms.
- Strong understanding of software lifecycle automation and distributed systems.
- Ability to work independently with unfamiliar codebases and APIs.
- Experience using Git and delivering clean, reviewable changes.
Important: Experience configuring Jenkins pipelines, managing Kubernetes deployments, or using CI/CD services is not sufficient on its own. We are specifically seeking engineers who understand how these systems are built and extended.

### Preferred Experience
- Contributions to open-source CI/CD or platform engineering projects.
- Familiarity with CDEvents and CloudEvents.
- Experience with event-driven orchestration or workflow engines.
- Experience building DSLs, parsers, or declarative workflow systems.
- Experience with observability, event correlation, or automated remediation.
- Experience building developer platforms or internal developer platforms (IDPs).

### How to Apply
Please include the following in your proposal:
1. Tooling Development Experience: Identify an SDLC or platform engineering tool you have built, extended, or contributed to. Describe your actual code contributions rather than how you used the tool.
2. Code Examples: Provide GitHub links, pull requests, or other evidence of relevant engineering work.
3. Go Experience: Describe a Go project involving plugins, event processing, workflow orchestration, or comparable systems.
4. Approach: Briefly describe how you would approach learning an unfamiliar orchestration engine, extending its DSL, and verifying the behavior through simulation.

Generic proposals listing CI/CD technologies without demonstrating actual tooling development experience will not be considered.

### Future Opportunities
This engagement is an opportunity to work directly with an emerging open-source orchestration platform.

Successful completion may lead to additional development engagements involving Conduit, Koine, and other Sol Duara projects.

We are looking for an engineer who enjoys understanding how systems work, extending their capabilities, and solving problems at the infrastructure level.

We’re building an RWA tokenization marketplace MVP and need a Full-Stack Developer to develop and improve frontend and backend functionality, ensuring the platform is scalable, secure, and reliable. The initial MVP uses Node.js, with plans to evolve the backend architecture as the project grows.

# Senior Ruby on Rails Engineer for Production Applications

We’re looking for an experienced Ruby on Rails engineer to build and support production applications at enterprise scale. You’ll own features from design through release, working closely with product, QA, and platform teams.

## What you’ll do

- Design, build, test, and maintain Rails features and backend services.
- Design and integrate RESTful APIs.
- Model relational data and improve ActiveRecord and SQL query performance.
- Troubleshoot production issues and help keep applications reliable.
- Participate in code reviews and CI/CD delivery workflows.
- Collaborate across the full product delivery cycle.

## Required qualifications

- Strong, hands-on Ruby on Rails experience supporting production applications.
- Solid Ruby fundamentals and familiarity with Rails conventions.
- Experience designing, developing, and integrating REST APIs.
- Practical relational database experience, including schema design, ActiveRecord, and SQL tuning.
- Automated testing experience with RSpec or Minitest.
- Comfortable with Git, code review, and CI/CD workflows.
- Bachelor’s degree in Computer Science or equivalent practical experience.

## Nice to have

Experience with one or more of the following:

- Go (Golang) backend services or Java enterprise and microservices development.
- Sidekiq or Resque.
- Docker or Kubernetes.
- AWS, GCP, or Azure.
- Redis or Elasticsearch.

##Services preferably required in Austin, TX

## To apply

Please include:

1. A brief summary of your production Rails experience, including the types of applications you’ve supported.
2. One example of a Rails feature, API, or performance issue you handled, and your role in the work.
3. The testing tools and deployment workflows you’ve used.
4. Any experience with the nice-to-have technologies listed above.

We are seeking an engineer who has personally built, modified, or maintained a Claude subscription-account integration gateway and operated a working solution. You must be able to demonstrate your contribution and results with existing test or operational evidence. General AI application development, API calls, or MCP usage alone is not sufficient.

We evaluate measured outcomes and practical engineering ability. We welcome different implementation approaches and do not require an identical past technology stack. Your solution must support our customer workflows and be compatible with our platform.

## Engagement Process

### 1. Review your existing experience and evidence

Describe a comparable system you personally worked on, a real stability issue you resolved, your changes, and the outcome. Provide existing redacted reports, logs, screenshots, or code evidence you are authorized to share. Include the running version, observation period, account/user scale, workload, measured reliability and latency, and known limitations. Clearly distinguish actual usage from simulations. No unpaid development or custom testing is required to apply.

### 2. Prepare a paid pilot in your environment

After agreeing the scope and fee, deploy your existing solution in an isolated environment you manage. We provide a domain. Use our base code as agreed, or a mutually approved compatible integration, focusing on Claude integration and account operational stability.

The pilot must include one-click configuration, one-click installation, and other agreed essentials needed for actual customer use. Adaptation, deployment, and support are paid work. New online-payment development is not required for the pilot; our team will manage test balances through the admin interface.

Preserve existing customer-facing features and business workflows. Any necessary changes require prior agreement on their purpose, impact, compatibility, and regression checks.

### 3. Test with real customers and retain complete data

After functional and readiness checks, we organize real customers to use one solution at a time. We cover Claude test-account and subscription costs, plus other direct testing expenses agreed in advance. Engineering fees are agreed separately.

We will agree on the observation period, workload records, acceptance metrics, and support arrangements before testing. Evaluation includes task completion and quality, reliability, latency, failures, known limitations, and actual costs.

All project-specific user data, test records, runtime logs, metrics, incident records, and analysis reports generated or lawfully collected during the pilot belong to us, subject to applicable user rights and privacy obligations. Retain them in full and provide client access and export for independent verification. Do not delete, overwrite, alter, or selectively withhold records without our written approval. Necessary corrections must preserve the originals, reasons, and audit trail.

### 4. Decide on code acquisition from the results

We decide whether to acquire the code only after reviewing complete real-customer test results. Purchase is not guaranteed. Agree the code price, transferable rights, third-party dependencies, temporary pilot-use license, and handover scope before the pilot. Open-source and third-party components remain subject to their licenses.

Payment for agreed pilot work does not depend on our decision to purchase the code or commission a later phase.

### 5. Integrate, deploy, and revalidate on our servers

If acquisition and the subsequent implementation scope are agreed, integrate the solution with our customized platform and deploy it on our servers. Revalidate existing workflows and stability with comparable workloads and metrics, documenting environment differences. Deliver the agreed source code, change notes, deployment and rollback documentation, and maintenance support.

## Existing Platform

Our team reports a customized platform based on open-source Sub2API v0.2.9, with existing improvements to log analysis, account and network operations, and Claude compatibility and stability. The reported environment is Go 1.27.3, PostgreSQL 18.6, and Redis 8.10.2; actual versions and configuration will be verified at kickoff.

These are compatibility requirements, not restrictions on your previous technology stack or proposed implementation. Alternative approaches are welcome when their compatibility, impact, and validation method are clear and mutually agreed. The pilot does not authorize unrelated feature changes or changes to our existing payment workflows.

## Terms and Application

Each phase will use a paid Upwork milestone with an agreed scope, schedule, fee, and acceptance criteria. Pre-contract communication and all freelancer payments remain on Upwork. Work must use authorized resources and comply with applicable provider terms.

Apply with a relevant project, your personal contribution, existing evidence, availability, and phase pricing. Do not share confidential client material or credentials.

## Screening Questions

1. Which Claude subscription integration gateway did you personally develop, modify, or maintain? Describe the access method, your contribution, and one real operational problem you resolved. Distinguish this from official API-only or MCP experience.
2. What existing evidence can you share for that solution's results? Include the running version, observation period, workload and scale, measured outcomes, and known limitations. Identify simulated results separately.
3. Can you provide a paid pilot in your environment with the agreed customer workflows and complete data access for us? State your availability, phase pricing, and principal dependencies. A free implementation plan is not required.

We are Nana, a female-founded startup building a science-backed nutrition and performance coach for female endurance athletes.

We’re tackling the massive gender bias in sports nutrition and are building a tool that adapts to real women’s physiology, goals, and daily realities. We aren’t building a cycle tracker or a calorie counter. We are building a brain that helps female athletes fuel better. One that learns. One that listens.

We’re looking for an engineer to join us in making this vision a reality. Someone who is comfortable building an adaptive algorithm, as well as a slick Flutter-based mobile app for our users to interact with.

**What you will do**

- Build Nana’s brain. You’ll be the architect and the co-owner of our Flutter mobile app and personalisation engine. This includes building logic to adapt fueling advice to a user’s cycling, training, and personal goals. All grounded in scientific data
- Craft a frictionless product experience, shaping intuitive interfaces for athletes and their coaches
- Work closely with our physiology and nutrition experts. You’ll translate scientific decision trees and behavioural logic into user-friendly, scalable tech
- (Co-)Own the full tech stack. You’ll lay the foundation for a product that’s ready to serve millions of women
- You’ll help shape product direction, tech strategy, and the future of AI in women’s health

**You might be a fit if you…**

- Have 5+ years of full-stack experience
- Have experience building and shipping mobile applications in Flutter
- Have experience using relational databases such as PostgreSQL
- Have experience designing and building a clean API (REST / OpenAPI / …). We have built ours in Golang
- Have experience in applied machine learning, behavioural modelling, or decision engines
- Love automated testing and clean code, and have a less-is-more mentality
- Are comfortable handling the day 1 and day 2 aspects of an early-stage SaaS solution (Containers, Railway/Mender, observability stacks)
- Are comfortable working in a small team
- Have a genuine interest in (women’s) sports, female physiology and its impact on performance

**Bonus points if you…

- Have worked in healthtech, sportstech, or applied AI/ML products
- Know your way around wearable data (Garmin, Whoop, etc.)
- Are a sucker for products that don’t need a user manual
- Love dog cuddles and don’t mind the occasional amount of pooch fluff on your black sweater

**What we offer**

- The opportunity to enter a massive, underserved market and a chance to shape the future of how women fuel, train, and thrive
- Collaboration with brilliant experts in female physiology, nutrition, and sports science
- A bullshit-free, ego-free, humour-filled work environment

We are seeking an experienced, senior-level backend engineer to help build the core data processing architecture for a health-tech compliance and verification SaaS platform.
The core of this project involves constructing a secure, robust data-ingestion pipeline that queries multiple external data sources, orchestrates API workflows, and evaluates complex data sets with high precision.

Key Responsibilities:
• Design and implement secure backend data pipelines and workflows.
• Integrate and orchestrate multiple external third-party RESTful APIs.
• Implement structured conditional logic and scoring matrices to process incoming data payloads.
• Optimize database queries for low-latency lookups and updates.
• Ensure data architecture adheres to high security and encryption standards.

Required Technical Skills:
• High proficiency in backend languages (e.g., Python, Node.js, or Go).
• Extensive experience with API orchestration, handling asynchronous requests, and error-handling routines.
• Strong database management skills (PostgreSQL, MySQL, or similar).
• Experience writing clean, well-documented, test-driven code.
• Familiarity with healthcare data security standards; ability to design backend infrastructure aligned with standard HIPAA technical safeguards (secure access controls, audit logs, and data encryption at rest and in transit).

Project Type & Workflow:
This will be a milestone-based, fixed-price project. We have completed the full system architecture blueprints and logical flowcharts.

IP & NDA Requirement:
Intellectual property protection is paramount for this project. Candidates will be required to sign a standard Non-Disclosure Agreement (NDA) with an Intellectual Property Assignment Agreement before we share the detailed technical specifications, algorithm logic, or system diagrams.

If you are a disciplined backend engineer who takes pride in building secure, high-performance data workflows, please submit your proposal with a brief summary of your experience handling complex API pipelines and secure environments.

Various new features added to an existing app based on requests received by clients

Job Description
We operate a live AI gateway built with Go, PostgreSQL, Redis, and Docker, with real production traffic and request logs. Our current integration includes Claude subscription accounts.
We are looking for an experienced engineer to investigate account suspensions and account-level restrictions, develop a systematic improvement plan, and lead its implementation.
Our reported incidents include accounts becoming restricted during use, restrictions discovered immediately after authorization or login, and restrictions discovered when no users were actively chatting. The underlying causes have not yet been confirmed.
Responsibilities
- Investigate account suspensions, account-level restrictions, and related authorization issues using incident timelines, platform notices, request logs, and system behavior.
- Distinguish confirmed findings from hypotheses, integration defects, and upstream platform limitations.
- Develop an overall plan covering investigation priorities, alternative approaches, implementation stages, resource requirements, and evaluation methods.
- Lead relevant changes to code, configuration, and integration workflows, and follow through on incident recovery and results.
- Improve logging, monitoring, alerting, testing, rollback procedures, and operational documentation.
- Recommend further gateway, protocol compatibility, capacity, isolation, and security improvements based on evidence and business priorities.
Required Experience
- Hands-on experience investigating actual account suspensions, deactivations, or account-level restrictions and implementing improvements. Experience limited to routine token expiration, refresh failures, or session expiry should be identified separately.
- Direct experience with Claude subscription integrations is preferred. Relevant experience with comparable platforms is also welcome, provided you can explain its applicability and limitations.
- Ability to describe your personal contribution, the evidence you examined, changes you implemented, observed results, and follow-up period.
- Strong backend debugging and implementation skills, with the ability to work in our existing Go, PostgreSQL, Redis, and Docker environment.
- Understanding of reverse proxies, HTTP request flows, OAuth, credential lifecycle management, network troubleshooting, and production incident investigation.
- Ability to propose a coherent solution, explain trade-offs, and identify which tasks you can deliver independently and where collaboration is needed.
Preferred Experience
- Production maintenance of AI gateways or similar integration services.
- Source-code analysis or practical modifications involving Sub2API, Claude Relay Service, New API, or One API. Familiarity with every project is not required.
- Observability, protocol compatibility testing, incident recovery, and reliability engineering.
Interview Process
We will discuss one of your previous cases and five incidents from our own system. We will assess your practical experience, independent judgment, overall approach, and implementation ability.
We do not prescribe a particular tool or algorithm. Candidates who meet the requirements and agree on the engagement terms can be hired directly. Detailed investigation and implementation take place after hiring; unpaid production fixes or complete implementation plans are not required during the interview.
Work is limited to company-owned systems, authorized accounts, and approved environments. The role does not involve identity spoofing, KYC bypasses, or circumventing third-party platform protections.
How to Apply
Please briefly describe one relevant account-suspension or restriction case, your personal role, the integration method, the actions you took, and the outcome. You may discuss sanitized evidence or explain the process without disclosing confidential information.

We are looking for a talented, AI-native software engineer to help build and scale Ampersand's integration infrastructure for enterprise agents.

Ampersand: ampersand.ai and Ampersand docs: docs.ampersand.ai

Ampersand helps enterprise software companies and AI agents connect deeply with their customers' systems of record, including Salesforce, NetSuite, SAP, and hundreds of other platforms. We're building the infrastructure, tooling, and AI-powered engineering workflows that make complex enterprise integrations dramatically easier to build, deploy, and maintain.

**What you'll work on:**

- Build and extend connectors in Go across CRMs, ERPs, and other enterprise systems of record.
- Work with complex APIs, authentication flows, data models, and customer-specific configurations.
- Collaborate with Andi, Ampersand's AI integration engineer, to accelerate connector development, testing, debugging, and maintenance.
- Use AI coding tools extensively to move faster while maintaining high engineering quality.
- Help build the tooling and workflows that enable AI agents to develop, test, and maintain integrations autonomously.
- Improve the reliability, performance, and scalability of our connector infrastructure.

**What we're looking for:**

- Strong fundamentals in Go, APIs, distributed systems, and backend engineering.
- Hands-on experience building software with AI coding tools such as Claude Code, Codex, or Cursor.
- A strong understanding of how to use AI effectively, including reviewing generated code, debugging failures, and validating correctness.
- Curiosity about how AI agents work and how they can automate increasingly complex engineering tasks.
- High ownership, strong problem-solving skills, and a willingness to learn quickly.
- Early-career engineers and exceptional recent graduates are welcome.

You'll work with a small, experienced engineering team in San Francisco building critical infrastructure for the next generation of enterprise software. This is an opportunity to work at the intersection of backend engineering, enterprise systems, and AI-powered software development.

I need an expert developer for a new Cryptocurrency project, particularly someone with expertise in Blockchain and smart contracts.
Sir kindly please reply me....i am from Odisha 🇮🇳 India

We are seeking a talented front-end developer or UI/UX engineer to redesign and overhaul the client-facing workflow interface of our website. The project involves transitioning from a multi-page operational process into a streamlined, high-performance web experience.'

Looking for an expert to technically evaluate a kubernetes based open source project and share honest review it including the goal, future roadmap, architecture and current implementation.

# About Embold

Embold runs Creator Programs for Canadian brands. Our platform powers every program, and our network of 12,000+ vetted Canadian creators delivers the content. Our team handles strategy, negotiations, shipping, and payments. Clients keep final approval.

You would work on that platform: the web application our team uses to run programs, track real-time metrics, review content, and pay creators.

# The role

You will build and maintain features across our React frontend and Django backend. You will ship work end to end, from ticket to production, and help keep the codebase clean as it grows.

You will report to a senior engineer who will mentor you. Expect regular code reviews, pairing, and direct feedback on your technical growth.

# What you will do

- Build features across the React frontend and Django backend
- Fix bugs and work down the backlog with clear, written updates
- Contribute to services around the core app, including background jobs and image processing
- Learn from your senior engineer through code reviews and pairing
- Use AI tools in your daily work and tell us what works and what doesn't

# Requirements

- 3 to 5 years of software engineering experience, including 2+ years as a full-stack engineer
- 3+ years of React
- 2+ years of Django
- 1+ year of Docker
- 1+ year of prompt engineering

# Nice to have

- Golang experience
- Familiarity with AWS
- Experience building microservices

# What we would like to see

- At least one major project you completed without any AI assistance
- Public GitHub repos with your projects
- Samples of how you use AI in your work (prompts, workflows, or a short write-up)

Job Title:

Full-Stack Developer Required to Build a Custom White-Label CPaaS Platform (SMS, Meta WhatsApp, Voice Call, RCS)

Project Description:

We are a registered Telemarketer (TM) looking for an experienced Full-Stack Software Developer (or Agency) to build a robust, scalable, and secure White-Label CPaaS Application from scratch. The application must feature a centralized multi-tenant web dashboard allowing clients and resellers to manage multiple communication channels seamlessly.
The platform must be fully compliant with Indian telecom regulations, specifically integrating deep TRAI / DLT compliance filters before traffic processing.

Key Features & Modules Required:


1. Core Channels & Routing Modules

• Bulk SMS: Integration with telecom operators via high-throughput SMPP v3.4 and HTTP APIs. Must support TLV parameters for passing Indian DLT tags (Entity ID, Template ID) and handling high TPS traffic.
• Meta WhatsApp API: Integration with WhatsApp Cloud API (Meta Business Suite) for sending template messages, managing session chats, and setting up automated interactive flows.
• Voice Calls & Cloud Telephony: Triggering automated Voice SMS, IVR campaigns, and outbound dialing with local virtual number mapping.
• RCS (Rich Communication Services): API integration to send rich media messages with interactive CTA buttons, branding logos, and smart Fallback-to-SMS routing if RCS delivery fails.

2. Telemarketer & Administration Controls

• Multi-Tenant Dashboard: Separate logins for Admin (us), Resellers (who can oversell virtual credits), and End-Users (Clients).
• DLT Scrubbing & Validation Engine: A robust rules engine that scrubs messages against pre-approved DLT templates, headers (Sender IDs), and Entity IDs before sending them to the operator.
• Billing & Wallet System: Real-time prepaid wallet tracking for all sub-accounts with virtual credit management, automated low-balance alerts, and invoice generation.
• Live DLR Reporting & Analytics: High-performance database processing to handle millions of Webhook responses daily, displaying real-time delivery rates (Delivered, Failed, Pending) and click-through tracking for short URLs.

Technical Stack Preferences (Flexible based on recommendation):

• Backend: Node.js (Express/FastIFY), Python (FastAPI/Django), or Go (Golang) for high-performance API handling.
• Frontend: React.js, Vue.js, or Angular (Modern, clean, responsive UI).
• Database: PostgreSQL or MySQL (optimized for heavy logging and indexes) along with Redis for queuing and session storage.
• Infrastructure Architecture: Standard Linux environments (Ubuntu), containerized setup (Docker), or deployment on scalable cloud instances (AWS/DigitalOcean). Open to core gateway suggestions like Kannel or Jasmin if applicable.

Developer Requirements:

• Prior hands-on experience building SMS portals, telecom software, or CPaaS API platforms is mandatory.
• Deep understanding of SMPP protocol, HTTP Webhooks, and Meta API integration.
• Strong knowledge of the Indian telecom system (DLT architecture, PE-TM chain, and regulatory headers) is highly preferred.

Skills: PHP, Java, Android, Software Architecture, Node.js, React.js, Full Stack Development, API Development

At Ezzeldeen M tech, we're building the next generation of digital payment and financial technology solutions.

We are looking for a Backend Developer to help build and maintain scalable backend services for our platform. You'll work directly on core product features, backend services, and integrations.

### Responsibilities

* Develop and maintain backend services and APIs.
* Design and implement microservices-based solutions.
* Integrate with third-party services and internal systems.
* Optimize application performance, reliability, and scalability.
* Write clean, testable, and maintainable code.
* Collaborate with product and engineering teams to deliver new features.

### Required Skills

* Python (FastAPI)
* Golang
* Microservices Architecture
* PostgreSQL
* Redis
* RabbitMQ
* Docker
* Git
* Unit & Integration Testing

### Nice to Have

* AWS
* Kubernetes
* Elasticsearch
* CI/CD pipelines

### Preferred Experience

* 1–3+ years of backend development experience.
* Experience building and maintaining production APIs.
* Understanding of software design principles and scalable system architecture.

This is an ongoing project with the potential for long-term collaboration.

We are a software development consulting agency working with international clients, looking for an experienced 𝗧𝗲𝗰𝗵𝗻𝗶𝗰𝗮𝗹 𝗥𝗲𝗰𝗿𝘂𝗶𝘁𝗲𝗿 to help us identify and recruit highly skilled client-facing software engineers for long-term client projects.

This is a 𝗽𝗲𝗿𝗳𝗼𝗿𝗺𝗮𝗻𝗰𝗲-𝗯𝗮𝘀𝗲𝗱 𝗰𝗼𝗻𝘁𝗿𝗮𝗰𝘁𝗼𝗿 𝗿𝗼𝗹𝗲 with flexible working hours, a monthly base salary, and additional payments for qualified candidates.

𝗥𝗲𝘀𝗽𝗼𝗻𝘀𝗶𝗯𝗶𝗹𝗶𝘁𝗶𝗲𝘀
- Source and recruit senior to principal software engineers (8–20 years of experience).
- Recruit frontend, backend, full-stack, AI, cloud, and SaaS engineers.
- Screen candidates for technical expertise, fluent English communication, and client-facing skills.
- Conduct initial interviews and submit qualified candidate profiles with screening notes.
- Build and maintain a strong talent pipeline for ongoing recruitment needs.
- Target 𝟯–𝟱 𝗾𝘂𝗮𝗹𝗶𝗳𝗶𝗲𝗱 𝗰𝗮𝗻𝗱𝗶𝗱𝗮𝘁𝗲𝘀 𝗱𝗮𝗶𝗹𝘆, 𝟮𝟬–𝟮𝟱 𝘄𝗲𝗲𝗸𝗹𝘆, 𝗮𝗻𝗱 𝟴𝟬–𝟭𝟬𝟬 𝗺𝗼𝗻𝘁𝗵𝗹𝘆, prioritizing quality over volume.

𝗥𝗲𝗾𝘂𝗶𝗿𝗲𝗺𝗲𝗻𝘁𝘀
- 3+ years of technical recruiting experience.
- Proven experience sourcing senior software engineers for international or remote opportunities.
- Strong understanding of React, TypeScript, Node.js, Python, Java, PHP, C#, Golang, cloud technologies, and modern AI frameworks.
- Experience recruiting candidates from Pakistan, Indonesia, Eastern Europe, and other suitable regions.
- Excellent English communication and candidate evaluation skills.
- Strong sourcing skills using LinkedIn, GitHub, Boolean search, professional networks, and referrals.
- Ability to work independently and consistently deliver qualified candidates.

𝗖𝗼𝗺𝗽𝗲𝗻𝘀𝗮𝘁𝗶𝗼𝗻
- 𝗕𝗮𝘀𝗲 𝗦𝗮𝗹𝗮𝗿𝘆: $250/month
- 𝗣𝗲𝗿 𝗤𝘂𝗮𝗹𝗶𝗳𝗶𝗲𝗱 𝗖𝗮𝗻𝗱𝗶𝗱𝗮𝘁𝗲: $5 for each candidate who passes our initial qualification process.
- 𝗦𝗲𝗹𝗲𝗰𝘁𝗶𝗼𝗻 𝗕𝗼𝗻𝘂𝘀: $50 for each candidate ultimately selected (typically 1–2 selections per month).
- 𝗦𝗰𝗵𝗲𝗱𝘂𝗹𝗲: Flexible hours, no hourly tracking.
- 𝗘𝘃𝗮𝗹𝘂𝗮𝘁𝗶𝗼𝗻 𝗣𝗲𝗿𝗶𝗼𝗱: Initial 1–2 weeks of onboarding session before long-term collaboration.

𝗪𝗵𝗮𝘁 𝗪𝗲'𝗿𝗲 𝗟𝗼𝗼𝗸𝗶𝗻𝗴 𝗙𝗼𝗿

We value recruiters who understand software engineering, can identify genuinely experienced developers, and consistently deliver candidates with strong technical and communication skills.

We're looking for a reliable, long-term recruiting partner who focuses on quality, professionalism, and measurable results.

𝗧𝗼 𝗔𝗽𝗽𝗹𝘆

Please briefly share:
1. Your technical recruiting experience and successful placements.
2. Your sourcing methods and platforms.
3. Your experience recruiting senior engineers for international clients.
4. Your expected daily or weekly candidate delivery capacity.
5. Your availability and confirmation that you're comfortable with our compensation structure.

𝗪𝗲'𝗿𝗲 𝗿𝗲𝗮𝗱𝘆 𝘁𝗼 𝘀𝘁𝗮𝗿𝘁 𝗶𝗺𝗺𝗲𝗱𝗶𝗮𝘁𝗲𝗹𝘆 𝗮𝗻𝗱 𝗹𝗼𝗼𝗸 𝗳𝗼𝗿𝘄𝗮𝗿𝗱 𝘁𝗼 𝗯𝘂𝗶𝗹𝗱𝗶𝗻𝗴 𝗮 𝗹𝗼𝗻𝗴-𝘁𝗲𝗿𝗺 𝗽𝗮𝗿𝘁𝗻𝗲𝗿𝘀𝗵𝗶𝗽 𝘄𝗶𝘁𝗵 𝘁𝗵𝗲 𝗿𝗶𝗴𝗵𝘁 𝗿𝗲𝗰𝗿𝘂𝗶𝘁𝗲𝗿.

!!! WE NEED SOME ONE WHO GOT EXPERIENCE WITH WAF SECURITY - CLOUDFLARE CAPCTHA AND ANTI BOT SYSTEM IF YOU NOT EXPERTS ON THESE DONT SEND OFFER !!!!

We are looking for an experienced full-stack developer to build a scalable availability monitoring and client management system.
The system should:
Monitor availability of time-based service slots
Detect newly available dates
Capture and reserve the available Test date with the customer criteria
Notify clients in real time
Support multi-client configuration
Include an admin dashboard
This is a SaaS-style platform with queue processing and session management.

Core Requirements
Monitoring Engine
Continuous availability checking
Near real-time detection
Retry & error handling logic
Structured logging
Multi-Client Support
100 concurrent clients
Per-client configuration:
Location selection
Date range
Time preferences
Priority level
Notification System
Web App & Email and WhatsApp API integration
Real-time alerts
Status updates
Admin Dashboard
Live monitoring status
Client management
Detection history
System health indicators
Manual pause/resume control

Preferred Stack
Golang
Node.js
Playwright or similar automation framework
PostgreSQL
Redis / Queue system
React
Docker
Open to architectural suggestions.

Deliverables
Working MVP system
Source code
Live Training
Deployment documentation
1 Year Free Maintanence Support
¬will sign AMC or MMC after Free Period !

Skills: PHP, JavaScript, Software Architecture, Golang, Node.js, PostgreSQL, Docker, Web Development, Cloudflare, SaaS

I'm looking for an experienced Golang developer to fix a few authentication-related bugs in my existing backend application.
The authentication system is already implemented, but some issues need to be identified and resolved to ensure users can log in and access protected endpoints correctly.

Sanam is a Riyadh-based company. We build the infrastructure that experience providers in Saudi Arabia run on: tour operators, desert camps, diving centres and heritage guides. We handle their distribution (their own storefront, global OTAs and trade partners), their payments and invoicing, and the tools they use every day. Saudi Arabia is one of the fastest-growing travel markets in the world, and we are the operator's partner in it. See sanam.travel.

The role
You'll join our small engineering team and own features end to end, across our backend services and our web apps. You'll work directly with our Head of Engineering and the founders.

2,100 USD monthly Salary

What you'll work on

Backend services in Go, with some Rust: identity, billing, notifications, and the booking and inventory flows behind them
Integrations with OTAs, payment providers and Saudi e-invoicing (ZATCA)
Our operator app in React and TypeScript
APIs over HTTP and gRPC, PostgreSQL schemas and migrations
Shipping safely: tests, code review, CI in GitHub Actions, containers on Kubernetes
Design notes and docs the next engineer can follow

Our stack

Go and Rust services, gRPC with mutual TLS, PostgreSQL
Policy-based authorization with Open Policy Agent (Rego)
React 19, TypeScript, Vite, Tailwind CSS, TanStack Router, i18next (Arabic and English, right to left)
Bun, Biome, Vitest, Playwright
Kubernetes on Oracle Cloud (Riyadh region), Terraform, Ansible, GitHub Actions

What we're looking for

6+ years building production software, including 3+ years of Go
Solid TypeScript and React, and comfortable moving across the stack
Experience with payments, bookings, marketplaces or other systems where money moves
Strong relational data modelling and PostgreSQL
Clear code, clear pull requests, clear docs, and tests for what you ship
Security-minded by default: auth, secrets, least privilege
Good written English, and at least 4 hours of overlap with Riyadh time (GMT+3)

Nice to have

Rust in production
OTA or channel manager integrations (GetYourGuide, Viator) or payment gateways (mada, Visa, Apple Pay)
Saudi or GCC experience: ZATCA e-invoicing, SAMA rules, PDPL
Arabic
Kubernetes and infrastructure as code

How we work

A small team with high ownership: you take a feature from design to production
Written first: our rules, docs and reviews live in the repo
Full-time, as a long-term contract

To apply, answer these in your proposal

Tell us about a system you built where money moves (payments, payouts or billing). What was the hardest part, and how did you make it reliable?
Share a Go repository or code sample you're proud of, and tell us what you'd improve in it today.
How many hours a week can you give, and how many overlap with 9:00 to 17:00 Riyadh time?

Please start your proposal with the word "Arabia", so we know you read this far.

Needs to hire 2 Freelancers
Summary
We are hiring 2 experienced Full-Stack Engineers for long-term, full-time positions.

We are looking for skilled and motivated Full-Stack Engineers to join our growing development team. You will work on innovative AI-powered applications, building scalable backend systems, modern user interfaces, and integrating advanced AI/ML capabilities into real-world products.

We are seeking hands-on developers who are comfortable working across the entire technology stack, solving complex technical challenges, and delivering reliable, production-quality solutions.

Key Responsibilities

Design, develop, and maintain scalable full-stack applications.

Build and optimize backend services using Python, Golang, and FastAPI.

Develop responsive frontend interfaces using React, TypeScript, or similar technologies.

Integrate AI/ML models, LLMs, and intelligent automation into applications.

Develop APIs, microservices, and database integrations.

Work with cloud infrastructure, Docker, and CI/CD workflows.

Troubleshoot issues, improve application performance, and maintain code quality.

Collaborate with other engineers to deliver new features and improve existing systems.


Required Skills & Experience

Strong professional experience in full-stack software development.

Advanced proficiency in Python and FastAPI.

Hands-on development experience with Golang.

Strong knowledge of React, JavaScript, and TypeScript.

Experience building REST APIs and microservices.

Experience with SQL/NoSQL databases.

Familiarity with cloud platforms and containerized applications.

Practical experience integrating AI/ML technologies into software applications.

Strong problem-solving skills and ability to work independently.


Preferred Experience

Experience with LLMs, RAG systems, or AI agents.

Familiarity with LangChain, LangGraph, or similar frameworks.

Experience with Kubernetes and scalable cloud architectures.

Previous experience developing SaaS or enterprise applications.


Who We're Looking For

We are not looking for someone whose AI experience is limited to calling LLM or AI APIs.

We need an engineer who understands the AI/ML concepts and mathematics behind the technology, can reason through complex technical problems, and has the engineering skills to build the solution using Python, Golang, FastAPI, databases, and APIs.

You should be comfortable discussing an AI/ML problem at a conceptual and mathematical level and then opening your IDE and building the solution.

When Applying

1. Describe an AI/ML application you personally built. What did you design and code yourself? Please include the technologies used, your experience with Python, Golang and FastAPI, and how AI/ML concepts or mathematics were applied to the solution.

We are looking for an experienced full-stack developer to build a scalable availability monitoring and client management system.
The system should:
Monitor availability of time-based service slots
Detect newly available dates
Notify clients in real time
Support multi-client configuration
Include an admin dashboard
This is a SaaS-style platform with queue processing and session management.

Core Requirements
Monitoring Engine
Continuous availability checking
Near real-time detection
Retry & error handling logic
Structured logging
Multi-Client Support
100 concurrent clients
Per-client configuration:
Location selection
Date range
Time preferences
Priority level
Notification System
Email and WhatsApp API integration
Real-time alerts
Status updates
Admin Dashboard
Live monitoring status
Client management
Detection history
System health indicators
Manual pause/resume control

Preferred Stack
Golang
Node.js
Playwright or similar automation framework
PostgreSQL
Redis / Queue system
React
Docker
Open to architectural suggestions.

Deliverables
Working MVP system
Source code
Live Training
Deployment documentation
1 Year Free Maintanence Support

Skills: Golang, NoSQL Couch & Mongo, Node.js, Express JS, PostgreSQL, Redis, AngularJS, Docker, Full Stack Development, SaaS