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@closeio

Close

The inside sales CRM of choice for SMBs

About Us

At Close, we're building the sales communication platform of the future. With our roots as the very first sales CRM to include built-in calling, we're leading the industry toward eliminating manual processes and helping companies to close more deals (faster). Since our founding in 2013, we've grown to become a profitable, 100% globally distributed team of 90+ high-performing, happy people that are dedicated to building a product our customers love.

Our Tech Stack

Backend

Our backend tech stack currently consists primarily of Python Flask web apps with our TaskTiger scheduler handling many of the backend asynchronous task processing chores. Our data stores include MongoDB, PostgreSQL, Elasticsearch, and Redis. The underlying infrastructure runs on AWS using a combination of managed services like EKS, MSK, RDS and ElasticCache and non-managed services running on EC2 instances. All of our compute runs through CI/CD pipelines that build Docker images, run automated tests and deploy to our Kubernetes clusters.

Our backend primarily serves a well-documented public API and GraphQL endpoint that our front-end JavaScript app consumes. Our infrastructure is heavily automated using Terraform, Ansible and other AWS tools.

Frontend

Our app’s frontend is a single-page TypeScript web app mostly written in React (originally built with Backbone.js). Our mobile app is built using React Native. We bundle with Webpack and target only modern browsers. We test with Jest, React Testing Library, and Playwright. Our UI updates in near real-time and is written in LESS/CSS (with flexbox and grid layout) using CSS modules and takes advantage of fun technologies like Websockets and WebRTC.

We care about performance (e.g. route-based code splitting), maintainability, and testability of our frontend code. Our product development process is inspired by Shape Up. We sweat the UI/UX details and work collaboratively with the Product team throughout the design process. This means diving into lo-fi wireframes, and communicating continuously when those ideas are brought to life using Figma and code.

More about us

  • The Making of Close – Our behind-the-scenes Product & Engineering blog
  • Jobs at Close – We're hiring for our 100% remote team
  • About Us – Learn about us
  • API – Our REST API for developers wanting to integrate with Close

Pinned Loading

  1. tasktiger tasktiger Public

    Python task queue using Redis

    Python 1.4k 87

  2. react-custom-scroller react-custom-scroller Public

    Super simple React component for creating a custom scrollbar cross-browser and cross-devices.

    TypeScript 35 9

  3. ciso8601 ciso8601 Public

    Fast ISO8601 date time parser for Python written in C

    Python 568 48

  4. closeio-api closeio-api Public

    Python API Client for Close

    Python 69 48

  5. cleancat cleancat Public

    Validation and serialization library for Python designed to be used with JSON REST frameworks

    Python 52 8

  6. use-infinite-scroll use-infinite-scroll Public

    Super simple React hook for creating an infinite scroll experience based on the IntersectionObserver API

    JavaScript 37 8

Repositories

Showing 10 of 183 repositories
  • close-mongo-ops-manager Public

    Monitor and kill MongoDB operations

    closeio/close-mongo-ops-manager’s past year of commit activity
    Python 5 MIT 0 2 0 Updated Nov 2, 2025
  • github-retry-action Public Forked from nick-fields/retry

    Retries a GitHub Action step on failure or timeout

    closeio/github-retry-action’s past year of commit activity
    TypeScript 1 MIT 100 0 1 Updated Oct 29, 2025
  • socketshark Public

    A WebSocket message router based on Python/Redis/asyncio

    closeio/socketshark’s past year of commit activity
    Python 124 MIT 12 2 20 Updated Oct 28, 2025
  • sync-engine Public
    closeio/sync-engine’s past year of commit activity
    Python 29 AGPL-3.0 12 30 40 Updated Oct 26, 2025
  • github-test-reporter Public Forked from ctrf-io/github-test-reporter

    Publish and view test reporting directly in your GitHub Actions CI/CD workflow and Pull Requests with detailed test summaries, failed test analyses, and flaky test detection.

    closeio/github-test-reporter’s past year of commit activity
    TypeScript 0 MIT 35 0 0 Updated Oct 14, 2025
  • currents-cancel-run-gh-action Public Forked from currents-dev/cancel-run-gh-action

    A GitHub action used to cancel Currents runs when the GitHub workflow is canceled

    closeio/currents-cancel-run-gh-action’s past year of commit activity
    TypeScript 0 MIT 4 0 0 Updated Oct 6, 2025
  • flanker-new Public

    Flanker (forked from mailgun)

    closeio/flanker-new’s past year of commit activity
    Python 3 Apache-2.0 0 0 1 Updated Oct 2, 2025
  • tasktiger Public

    Python task queue using Redis

    closeio/tasktiger’s past year of commit activity
    Python 1,446 MIT 87 27 19 Updated Sep 15, 2025
  • closeio-desktop-releases Public

    Releases for the Close macOS and Windows Desktop application

    closeio/closeio-desktop-releases’s past year of commit activity
    1 0 0 0 Updated Sep 4, 2025
  • ciso8601 Public

    Fast ISO8601 date time parser for Python written in C

    closeio/ciso8601’s past year of commit activity
    Python 568 MIT 48 15 (3 issues need help) 1 Updated Aug 20, 2025