# Free Tier

Google’s app development platform for backend, auth, database, hosting, analytics, and AI features

Firebase is Google’s app development platform providing backend services including Firestore, Realtime Database, Authentication, Cloud Storage, Cloud Functions, Hosting, Analytics, messaging, and AI-connected app features. Current docs foreground Firebase AI Logic for Gemini API access, Genkit for full-stack AI and agentic apps, Firestore vector search, and SQL Connect. Spark plan is free; Blaze is pay-as-you-go.

AI developer productivity platform with stacked PRs

Graphite is an AI-powered developer productivity platform that combines stacked pull requests with intelligent code review. Its AI agent catches real bugs with an under 3% unhelpful comment rate and offers one-click fixes directly in the PR flow. The stacked PR workflow breaks large changes into smaller, sequenced diffs that merge independently, keeping developers unblocked. Includes a stack-aware merge queue, CLI tool, VS Code extension, unified PR inbox, and deep GitHub integration.

Open-source LLM observability through a single-line proxy

Helicone is an open-source LLM observability and AI gateway platform with proxy-based request logging, cost tracking, latency monitoring, caching, rate limits, user analytics, prompt tools, and HQL. It supports OpenAI, Anthropic, Azure, LiteLLM, Anyscale, Together AI, and OpenRouter integrations, and now presents itself as part of Mintlify while continuing managed and self-hosted gateway/observability workflows.

Cloud cost estimates for Terraform changes in pull requests

Infracost shows cloud cost changes directly in pull requests before infrastructure-as-code changes are deployed. It calculates cost impact across AWS, Azure, and GCP for Terraform, Terragrunt, CloudFormation, and AWS CDK workflows, with diffs in GitHub, GitLab, Bitbucket, and Azure DevOps. 12.4K+ GitHub stars, Apache 2.0 licensed. Used by GitLab, HelloFresh, JPMorgan Chase, BMW, and Accenture.

Run local LLMs with an intuitive desktop GUI and OpenAI-compatible API server.

Free desktop application by Element Labs for discovering, downloading, and running open-source LLMs locally. Features a curated Hugging Face model browser, side-by-side model comparison, parameter tuning, and an OpenAI-compatible API server on localhost:1234. Powered by llama.cpp with Metal acceleration for Apple Silicon.

Open-source terminal AI agent by Alibaba

Apache-2.0 terminal coding agent with Qwen, OpenAI, Anthropic, Gemini, third-party, and local-model support. Qwen OAuth free access ended on April 15, 2026; use Alibaba ModelStudio, a provider API key, or a self-hosted endpoint.

Infrastructure, instantly

Modern cloud platform for deploying full-stack apps, databases, and workers with instant provisioning and usage-based pricing. Deploy from GitHub or CLI with zero config for Node.js, Python, Go, Rust, and Docker. Built-in PostgreSQL, MySQL, Redis, and MongoDB with auto backups. Features private networking, environment management, cron jobs, TCP proxying, and real-time logs. Popular with indie hackers and startups for fast MVPs with a generous free trial including $5 monthly credits.

Autonomous AI pentester for web apps and APIs

Shannon is an autonomous white-box AI pentesting tool for web applications and APIs. It analyzes authorized source code, identifies attack vectors, attempts proof-by-exploitation, and produces remediation-ready reports. Shannon Lite is AGPL-3.0 for local use, while Shannon Pro is the commercial Keygraph platform for continuous security testing.

Code intelligence platform

Code intelligence platform providing universal code search across all repositories, languages, and code hosts. Search with regex, structural patterns, and diff/commit search across GitHub, GitLab, Bitbucket, and self-hosted repos. Features code navigation (go-to-definition, find references) in the browser, batch changes for large-scale refactoring, code insights for tracking metrics, and Cody AI assistant for code generation and explanation. Self-hosted and cloud options.

Go implementation of the Model Context Protocol SDK

mcp-go is a Go implementation of the Model Context Protocol, providing both server and client SDKs for building MCP integrations in Go. It supports stdio and SSE transports, resource management, tool registration, and prompt templates. Designed for Go developers building MCP servers for DevOps tools, CLI applications, and backend services. Over 8,000 GitHub stars.

Free AI code completion supporting 70+ languages

AI-native code editor (now operating as Windsurf) built on VS Code with the Cascade agentic assistant for multi-file editing, terminal execution, and codebase-wide context. Codeium supports 70+ programming languages with lightning-fast completion, Cascade Memories for customizable AI behavior, semantic indexing, and automatic linter-error fixes — combining completion plus full agent in one cohesive IDE.

Web platform for modern development

Jamstack-focused cloud platform specializing in deploying static sites, serverless functions, and modern web applications with Git-based CI/CD. Features instant rollbacks, deploy previews for every PR, split testing, edge functions, form handling, identity/auth, and a global CDN with automatic HTTPS. Native support for Next.js, Nuxt, Gatsby, Hugo, Astro, and all major static site generators. Free $0 forever plan plus Personal and Pro credit-based tiers for growing traffic and team workflows.

Full-stack observability with AI-powered monitoring

New Relic is a full-stack observability platform combining APM, infrastructure monitoring, logs, traces, browser/mobile monitoring, synthetics, and AIOps. Current public copy highlights 50+ capabilities, 100 GB/month free data ingest, one free full platform user, unlimited basic users, and 800+ pre-built integrations.

Managed SonarQube Cloud code quality and security analysis for CI/CD workflows.

SonarQube Cloud, still commonly associated with the SonarCloud name, is SonarSource’s managed code quality and security SaaS for GitHub, GitLab, Bitbucket, and Azure DevOps. It scans pull requests for bugs, vulnerabilities, security hotspots, code smells, duplication, and coverage regressions, then enforces Quality Gates without running SonarQube Server. Current Sonar docs frame the cloud service around 40+ languages, with Team from $32 monthly and Enterprise custom.

AWS AI coding assistant with code generation and security scanning

AI coding assistant from AWS with inline code suggestions, chat, code transformation, and built-in security vulnerability scanning. Deep integration with AWS services and CLI makes it particularly powerful for cloud-native development. Helps developers modernize legacy code, optimize AWS resource usage, and implement security best practices across their entire development workflow.

Terraform pull request automation via GitHub/GitLab comments

Atlantis is a self-hosted Terraform pull request automation tool that runs plan and apply operations triggered by GitHub, GitLab, Bitbucket, or Azure DevOps comments. Type 'atlantis plan' on a PR to see infrastructure changes, then 'atlantis apply' to deploy. 9,100+ GitHub stars, Apache 2.0 licensed. Widely adopted as the standard for GitOps-style Terraform workflows, with locking to prevent concurrent modifications to the same resources.

Automated code quality

Codacy is a managed code quality, security and AI-guardrails platform for GitHub, GitLab and Bitbucket teams. It scans pull requests and repositories for quality, coverage and security issues while adding AI Inventory, AI Guardrails, AI Risk Hub, AI Reviewer and Verity beta surfaces for AI-assisted engineering.

Tool infrastructure for AI agents

Composio connects AI agents to 1,000+ app toolkits with managed auth, delegated user connections, sessions, tool search, MCP gateway support, CLI workflows, and sandboxed workbench execution. It targets developers building Claude, Codex, Cursor, LangChain, CrewAI, OpenAI Agents SDK, and custom agent workflows that need authenticated business actions without hand-rolling every API integration.

High-performance open-source web crawler optimized for AI pipelines

Crawl4AI is an open-source Python web crawler built for AI and data-pipeline use cases. It produces LLM-ready Markdown, supports structured extraction, Playwright/browser automation, deep/adaptive crawling, proxy/security controls, anti-bot fallback patterns, and multiple output formats. With 68K+ GitHub stars and Apache-2.0 licensing, it is a strong local/self-hosted option for RAG datasets and agent data collection.

AI-native Git client with virtual branches and smart commits

GitButler is a source-available Git client for virtual/stacked branches, AI-assisted workflows, and intelligent conflict resolution. Co-founded by Scott Chacon, it helps developers organize commits and work on multiple changes simultaneously. 21K+ GitHub stars; FSL-1.1-MIT license model.

Cloud development environments

Gitpod is an open-source cloud development environment platform that launches ephemeral, pre-configured workspaces in seconds from any Git repository on GitHub, GitLab, or Bitbucket. Configured via .gitpod.yml, it ships a full VS Code / JetBrains IDE, cached prebuilds, and workspace snapshots — eliminating 'works on my machine' for distributed teams and open-source contributors.

API development and testing platform

The most popular API platform used by 30M+ developers worldwide. Build, test, and document APIs with collections, environments, automated testing, and team collaboration. Features mock servers, monitoring, API design tools, and a vast public API network. The industry standard for API development workflows from prototyping through production testing and documentation.

Open-source LLMOps platform for prompt management and evaluation

Agenta is an open-source LLMOps platform that combines prompt engineering playgrounds, prompt version management, LLM evaluation, and observability in a unified interface. It supports 50+ LLM models with side-by-side prompt comparison, A/B testing, human evaluation workflows, and OpenTelemetry-native tracing. Self-hostable with 4,000+ GitHub stars.

The LLM anti-framework for typed AI apps

Mirascope is an open-source Python and TypeScript toolkit for building LLM applications that prioritizes type safety, composability, and 100% test coverage. Positioned as the 'anti-framework,' it provides fine-grained control over LLM interactions using familiar language constructs rather than rigid abstractions, supporting all major providers through a unified interface.

Observability platform purpose-built for Python and Pydantic AI apps

Pydantic Logfire is an observability platform built by the Pydantic team specifically for Python AI applications. It provides structured logging, distributed tracing, and metrics with native understanding of Pydantic models, FastAPI, and AI framework data types. Auto-instruments OpenAI, Anthropic, LangChain, and other LLM providers. Built on OpenTelemetry for vendor-neutral data export. Offers a managed cloud dashboard with a generous free tier for development and small-scale production use.

Build software with AI

Browser-based IDE and cloud platform with a built-in AI agent that builds full-stack applications from natural language prompts. Supports 50+ languages with instant hosting, multiplayer collaboration, built-in databases (PostgreSQL, key-value), secrets management, and one-click deployment. Used by 30M+ developers for prototyping, learning, and shipping apps. Features Ghostwriter AI for code completion. Popular for hackathons, education, and rapid MVP development.

Design and publish production websites

Visual website builder combining intuitive design tools with one-click publishing. Create responsive, animated sites without writing code, with React-based output under the hood. Includes built-in CMS, forms, and analytics. Popular among designers and startups who want pixel-perfect websites with interactions and animations that rival custom-coded sites.

xAI conversational AI with real-time X/Twitter data

Conversational AI by xAI with real-time access to X (Twitter) data and web search. Excels at current events, humor, and unfiltered responses. SuperGrok plan includes advanced reasoning, image generation, and DeepSearch capabilities. Positioned as the AI assistant most connected to real-time social discourse, with unique strength in analyzing trending topics and public sentiment from the X platform.

Scalable browser infrastructure for AI agents

Hyperbrowser is a cloud browser platform for AI agents and automation, providing managed Chrome sessions through Playwright, Puppeteer, CDP, REST, Python, and Node.js SDKs. Docs cover Stagehand, stealth/proxy options, ad blocking, recordings, scraping APIs, and credit pricing without promising universal CAPTCHA or anti-bot bypass.

Spec-driven agentic IDE and CLI by AWS

Spec-driven agentic AI IDE from AWS, built on Code OSS (the VS Code foundation), that transforms ad-hoc prompting into a structured workflow by auto-generating requirements documents, design specs, and implementation plans before writing code. Kiro keeps AI-written code tied to explicit acceptance criteria defined up front.

LLM application observability and evaluation platform

LangSmith is LangChain's platform for debugging, testing, evaluating, and monitoring LLM applications in production. Provides detailed tracing of every step in LLM chains and agent workflows, dataset management for regression testing, prompt versioning, and automated evaluation with custom metrics. Features an annotation queue for human feedback, online monitoring dashboards, and integration with LangChain, LangGraph, and any LLM framework via the Python/JS SDK. Essential for production LLM ops.

Open-source dev environment management with AI integration

Daytona is secure, elastic infrastructure for running AI-generated code in isolated sandboxes. It gives agents and developer workflows programmable environments with dedicated kernel, filesystem, network, vCPU, memory, and disk, backed by OCI/Docker compatibility, SDK/API access, and under-90ms sandbox startup. The project has 72,000+ GitHub stars and is AGPL-3.0 licensed.

Run LLMs as a single portable executable file

Llamafile by Mozilla packages a complete LLM — model weights, inference engine, and OpenAI-compatible API server — into a single executable file that runs on Mac, Windows, Linux, FreeBSD, and OpenBSD with no installation. Built on llama.cpp and Cosmopolitan Libc for cross-platform portability, it delivers GPU-accelerated inference when available and falls back to optimized CPU execution. Supports GGUF models with a built-in web chat UI and REST API for integration.

AI code integrity platform for test generation and quality

Qodo, formerly CodiumAI, is an AI code integrity platform focused on reviewing, testing, and improving code quality across the development lifecycle. It provides AI-powered code reviews, automated test generation, and context-aware suggestions that span IDE, pull request, and CI/CD workflows. Qodo distinguishes itself from general-purpose AI coding assistants by focusing on quality assurance rather than code generation alone.

The modern terminal with AI

GPU-accelerated terminal built in Rust, now evolved into an Agentic Development Environment (ADE) used by 700K+ developers. Features block-based output navigation, AI command suggestions via the Oz orchestration engine, multi-line editing with syntax highlighting, and a built-in code editor with LSP support. Available on macOS, Linux, and Windows. Includes Warp Drive for sharing workflows, real-time session collaboration, and BYOK support for OpenAI, Anthropic, and Google API keys.

Open-source, local-first Notion alternative with built-in AI

AppFlowy is an open-source workspace platform offering documents, wikis, databases, and project management as a privacy-first alternative to Notion. Built with Rust and Flutter for native performance, it runs fully offline with local data storage by default. AI features include writing assistance, summarization, and translation powered by configurable LLM providers. 72.5K+ GitHub stars, backed by a growing contributor community with self-hosted and cloud deployment options.

Git-friendly offline API client

Open-source API client for testing REST, GraphQL, and gRPC APIs as a lightweight, privacy-focused alternative to Postman. Stores API collections as plain files in your Git repository for easy version control and team collaboration. Features environment variables, scripting, collection runner, and a declarative syntax called Bru. Offline-first with no cloud account required. Available on macOS, Windows, and Linux. 44K+ GitHub stars and growing rapidly among developers leaving Postman.

Google's enterprise AI coding assistant powered by Gemini

Gemini Code Assist is Google's business AI coding assistant for VS Code, JetBrains IDEs, Cloud Workstations, GitHub, and Google Cloud workflows. Standard and Enterprise plans include Gemini 3, a 1M-token context window, Gemini CLI access, preview agent mode, code completion, chat, transformation, PR review, and enterprise governance controls for GCP-heavy teams.

AI coding agent by Moonshot AI

Terminal-based AI coding agent from Moonshot AI, powered by Kimi K2.5 with a 256K context window that achieves 76.8% on SWE-Bench Verified. Reads and edits code, executes shell commands, fetches web pages, and autonomously plans multi-step development workflows through natural language. Moonshot's entry into the AI coding agent market, leveraging their strength in large-context language models.

All-in-one open-source observability — logs, metrics, traces, RUM

OpenObserve is an open-source observability platform that unifies logs, metrics, traces, and real user monitoring in a single binary. It claims 140x lower storage costs than Elasticsearch through columnar storage and compression, with native OpenTelemetry support, a built-in query UI, dashboards, and alerts. Designed for AI and cloud-native workloads at petabyte scale. Over 15,000 GitHub stars.

Industry-standard incident management and on-call alerting platform

PagerDuty is an enterprise incident management platform for on-call scheduling, alert routing, escalation policies, and incident response orchestration. It integrates with 750+ monitoring, ticketing, cloud, and collaboration tools, including Datadog, Slack, Jira, AWS, and Microsoft Teams. Current pricing lists a Free tier for up to 5 users, Professional from $21/user/mo annually ($25 monthly), Business from $41/user/mo annually ($49 monthly), and Enterprise custom.

AWS AI assistant for terminal and code

Amazon Q Developer CLI is an agentic AI assistant from AWS that enhances the terminal experience with deep AWS integration, code generation, and natural-language command translation. Completes multi-step development tasks, troubleshoots AWS services, writes infrastructure code, and handles documentation lookups directly from the shell. Included with AWS accounts and integrates with existing AWS credentials.

Open-source API client

Hoppscotch is a free, open-source API development ecosystem for building, testing, documenting, and collaborating on APIs through a lightweight, fast web-based interface. It supports REST, GraphQL, WebSocket, MQTT, SSE, and Socket.IO protocols across web, desktop, and CLI clients. With 79K+ GitHub stars, 2.5M+ users, and 5M+ monthly API requests, Hoppscotch has become a leading open-source alternative to Postman for developers who prioritize speed, simplicity, and self-hostable workflows.

Open-source AI code review with hybrid AST-LLM

Kodus is an open-source AI code review platform that combines AST analysis with LLM reasoning to reduce noisy comments. Kody learns team standards, supports GitHub, GitLab, Bitbucket, and Azure DevOps, is model-agnostic across Claude, GPT, Gemini, Llama and OpenAI-compatible endpoints, and offers free/community, $10/dev monthly or $8/dev annual Teams, and Enterprise options.

Local microVM sandboxes for AI agent code execution

Microsandbox provides hardware-level isolated sandboxes for AI agents to execute code safely on local machines. Using libkrun microVMs and a 320ms bare-metal Linux/KVM homepage benchmark, it offers stronger isolation than Docker containers while staying lightweight enough for dev workstations. OCI-compatible with Python and Node.js runtimes. Apache-2.0 licensed with 6.6K+ GitHub stars.

Open-source codeless test automation with NLP-based test creation

Testsigma is an open-source codeless test automation platform where tests are written in plain English using NLP-based interpretation. It supports web, mobile, and API testing with self-healing test maintenance that adapts to UI changes automatically. Apache 2.0 licensed Community Edition is free with full functionality. Cloud edition adds parallel execution, integrations, and team management. Active development with regular releases through 2026.

OpenTelemetry-based observability SDK for LLM applications

Traceloop is an LLM reliability platform built around OpenLLMetry, an Apache-2.0 OpenTelemetry instrumentation layer for GenAI applications. It traces calls across OpenAI, Anthropic, vector databases, LangChain, LlamaIndex, and other frameworks, then sends data to OTel-compatible backends or Traceloop Cloud. Current positioning adds monitoring, evaluation dashboards, CI/CD integration, prompt management, and enterprise/on-prem options.

Continuous integration and delivery

Cloud CI/CD platform known for speed and Docker-first workflows. Offers parallelism, intelligent caching, and orbs (reusable configuration packages) for common tasks. Used by Spotify, Samsung, and Ford. Strong at complex build pipelines with conditional logic, matrix builds, and granular resource allocation that help large teams optimize their build times.