Replit

Not to be confused with Read–eval–print loop.

Replit, Inc

Logo
Formerly	Repl.it
Founded	San Francisco, California, U.S.
Founders	Amjad Masad Faris Masad Haya Odeh
Headquarters	Foster City, California
Number of locations	2 offices (2022)
Services	Community Hosting IDE
Website	replit.com

Replit (/ˈrɛplɪt/), formerly Repl.it, is an American AI company pioneering natural language application development through its Agent platform. Founded in 2016 as a online integrated development environment (IDE). Replit has evolved to focus on empowering non-technical users to create software without coding knowledge, contributing to its mission of enabling the next billion software creators.

History

Replit was co-founded by the Jordanian programmers Amjad Masad, Faris Masad, and designer Haya Odeh in 2016. It was incorporated in San Mateo. Its name comes from the acronym REPL, which stands for "read–evaluate–print loop". Replit has transformed from a collaborative coding platform into an AI-powered software creation ecosystem centered around "vibe coding" - the ability to build complete applications by describing them in natural language. The company's Agent technology converts plain English descriptions into functioning software, democratizing application development for users regardless of their technical background.

Before creating Replit, Amjad Masad worked in engineering roles at Yahoo and Facebook, where he built development tools. He also helped found Codecademy. Masad had come up with the idea for Replit over a decade before its creation.

In 2009, having seen significant advancements in browser and web technologies, Masad imagined a development environment built on the same premise as Google Docs; that is, allowing the user to write and share code all in a web browser. In 2011, he produced an early open-source version of this concept, called “JSRepl”. Because Masad then spent a few years working at various companies, including Udacity and Codecademy, JSRepl was used to power Udacity and Codecademy's in-browser tutorials.

During the formative years of Replit from 2012 to 2016, Haya Odeh as Co-Founder played a pivotal role in shaping the platform's accessibility and user experience. Initially starting with designing the logo and website after the name "Repl.it" was chosen. Between 2012 and 2015, Odeh refined her design philosophy centered on simplicity and inclusivity. In 2015, she created interface patterns that eliminated technical barriers for beginners while maintaining functionality for creators.

Formation, Growth, and Evolution (2016-2022)

Upon Replit's official incorporation in 2016, Odeh developed the comprehensive visual identity and design system that supported the platform's rapid growth to approximately 750,000 users by year's end. Her emphasis on making creating software accessible through intuitive design was instrumental in Replit's focus on and remains central to the company's mission of democratizing programming.

The platform evolved beyond its beginnings as a REPL (Read-Eval-Print Loop) environment to incorporate more sophisticated creation tools.

In December 2021, Replit raised $80 million in a Series B funding round led by Coatue.

AI Launch (2022-2024)

Ghostwriter is an AI-powered coding assistant developed by Replit and launched in October 2022. It was among the pioneering AI programming tools on the market, introduced during a period when AI coding assistance was still an emerging technology. Ghostwriter preceded GitHub Copilot's general availability, which was released to the public in June 2022 after an initial technical preview in 2021. Ghostwriter's initial feature set included Complete Code (an AI pair programmer providing real-time code suggestions), Generate Code, Transform Code, and Explain Code functionalities. The tool was designed to integrate directly into Replit's browser-based IDE, making it particularly accessible for coding on mobile devices. In 2023, Replit expanded Ghostwriter's capabilities by adding conversational features through Ghostwriter Chat, establishing it as one of the early comprehensive AI coding assistants in the rapidly evolving field of AI-assisted programming.

In April 2023, Replit reportedly raised $97.4 million at a post-money valuation of $1.16 billion in a Series B extension led by Andreessen Horowitz's Growth Fund, with participation from Khosla Ventures, Coatue, and others. In November 2023, the company secured an additional $20 million investment from Craft Ventures.

Agent Launch (2024-present)

The company launched Agent in September 2024, an AI tool designed to generate applications from natural language descriptions. Masad described it as "the first at-scale working software agent you can try in the world today." This launch represented Replit's transition from serving primarily professional developers to expanding software creation capabilities to non-technical users.

On February 25, 2025, Replit released Agent v2, a more autonomous version that helps build end-to-end software products using natural language.

Features

Agent Platform

Replit Agent is the company's primary product, allowing users to create applications using natural language descriptions. Users describe what they want to build, and Agent handles the technical implementation.

Agent v2, released in February 2025, includes enhanced capabilities according to the company. The system is designed to form hypotheses, search for relevant files, and make changes when it has sufficient information. This approach aims to reduce development roadblocks by enabling the system to reconsider its approach when encountering issues.

Features of Agent include:

• Application generation from natural language descriptions
• Setup of development environments and infrastructure
• Interface previews during application creation
• Handling of multi-file codebases while maintaining context
• Guided ideation process with recommendations for next steps

Vibe Coding Ecosystem

Replit describes its approach as "vibe coding," a method that enables software creation primarily through AI interaction. This methodology aims to make application development more accessible to non-technical users while providing a foundation for those who want to build technical knowledge.

The platform includes:

• Natural language interaction for software development
• App design previews that visualize concepts during development
• Cross-device functionality for various devices
• Integrated deployment capabilities
• Collaborative features

According to Replit, this approach is not intended to replace developers but to expand who can create software. Users can choose different approaches based on their goals:

• Non-technical approach: Describing an application to Agent for generation
• Hybrid approach: Starting with generated code and making modifications
• Learning pathway: Using the platform to build programming knowledge

Deployment and Infrastructure

Replit provides deployment capabilities that allow users to publish applications without manual server configuration. The platform includes features to adjust resources based on traffic, aiming to make application sharing and scaling more accessible.

The platform integrates cloud services including databases, object storage, and security features within a unified environment, designed to reduce technical barriers to deployment.

Development Environment

Replit maintains a browser-based development environment that requires no local installation. The platform supports multiple programming languages through the Nix package manager, which provides access to the Nixpkgs package database.

The environment includes collaborative coding features that allow multiple users to work simultaneously on projects. The platform offers real-time editing, messaging, and a shared compute engine that displays code execution to all participants.

For users who prefer direct code interaction, Replit offers development tools including source control via Git, debugging services, unit testing, and database capabilities.

Replit supports collaborative coding with the ability for multiple users to edit a shared repl, real-time edits across files, and instant messaging. Using a shared compute engine, code can be run and displayed the same to multiple users in a Repl.

Repl environments have built-in source control via Git on all Repls and users can switch branches, push files, and revert code. Replit allows for the pulling of code from a GitHub repository and linking Repls to GitHub repositories. Some Repls also have debugger and unit testing support. Replit uses the Debugger Adapter Protocol to provide debugging services in Java, Python, Node.js, and C++ for all users connected to a Repl. Replit has zero-setup unit testing in several languages. Repls also have secrets management, allowing users to hide values from others who see the Repl publicly. Repls also have databases with key-value data supported in Python, Node.js, and Go. Databases still can be accessed in other languages by using system calls.

What previously were called “Repls” are now “Replit Apps”, or just “Apps” for short.

Reception and Impact

Replit's AI-powered platform has been positioned by the company as expanding access to software creation by reducing technical barriers. The company states its mission as "empowering the next billion software creators" by making development accessible regardless of technical background.

According to Masad, "The internet is perhaps the biggest wealth generation technology ever created. If you make programming easier, you'll create more entrepreneurs globally. People with ideas and grit can change their lives in a fundamental way." This perspective frames software creation as an economic enabler that should be widely accessible.

Replit operates in a competitive landscape that includes other AI-assisted development tools and platforms, including GitHub Copilot, Amazon CodeWhisperer, and various natural language-to-code generation systems.

Masad has promoted the concept of "Amjad's Law," suggesting that the return on learning even basic coding knowledge doubles every six months due to increasingly capable AI tools. This principle underlies Replit's approach of making software creation accessible while providing pathways for users to build technical knowledge gradually.