Backed by 9,000+ GitHub stars and developed by a Germany-based team with deep FIDO2 expertise, Hanko delivers the open-source authentication platform that replaces Auth0, Clerk, and Firebase Auth with a passkey-first architecture built on phishing-resistant WebAuthn credentials. The Go backend exposes both public and administrative HTTP APIs handling passkey registration and login, password authentication, email passcodes, TOTP-based MFA, security key verification, server-side sessions with remote revocation, and JWT issuing with configurable expiry and refresh policies. OAuth SSO connects Apple, Google, GitHub, Microsoft, and custom OIDC providers, while SAML Enterprise SSO integrates corporate identity providers for single sign-on across the organization. Hanko Elements provides framework-agnostic web components that embed complete onboarding, login, and user profile flows into any application with two lines of code, fully customizable via CSS variables and supporting i18n with custom translations. The JavaScript frontend SDK handles API communication, credential management, and session state for teams building custom authentication UIs without the pre-built components. Webhooks notify external services of authentication events including user creation, login, email verification, and password changes. Privacy-first design principles enforce data minimalism with user-deletable passwords and configurable identifier strategies supporting email-only, username-only, or combined approaches. Docker deployment starts the backend with PostgreSQL or MySQL, serving both APIs on configurable ports. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 (backend) / MIT (frontend) licensed.

With over 36,000 GitHub stars and adoption by organizations including Adobe, Shopify, and Roblox, HashiCorp Vault is the industry-standard platform for secrets management, encryption services, and privileged access control across hybrid and multi-cloud infrastructure. The key/value secrets engine stores arbitrary secrets with full versioning, soft-delete, and metadata tracking, while dynamic secrets engines generate on-demand, short-lived credentials for AWS, Azure, GCP, databases including PostgreSQL, MySQL, MongoDB, and MSSQL, and SSH access with automatic revocation after configurable lease periods. The PKI secrets engine dynamically issues X.509 certificates on demand with automatic rotation and ACME protocol support, eliminating manual certificate management workflows entirely. Encryption as a service through the transit secrets engine lets applications encrypt, decrypt, sign, verify, and generate HMACs without managing cryptographic keys directly, supporting AES-GCM-256, ChaCha20-Poly1305, RSA-2048/4096, ECDSA-P256/P384, and ED25519 algorithms. Authentication integrates with LDAP, OIDC/OAuth2, SAML, AppRole for machine-to-machine access, Kubernetes service accounts, AWS IAM, Azure Active Directory, and GitHub tokens. Fine-grained ACL policies use path-based rules with glob patterns and sentinel policies for programmatic enforcement. The integrated Raft storage backend provides high-availability clustering without external dependencies, while alternative backends include Consul, S3, DynamoDB, PostgreSQL, and MySQL. The built-in web UI provides a visual interface for browsing secrets, managing policies, configuring auth methods, and monitoring cluster health. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. BSL 1.1 licensed.

Mox offers a complete mail server stack in a single Go binary requiring no external dependencies. The quickstart command configures a working mail server with SMTP, IMAP4, webmail, and full DNS authentication in under ten minutes. SMTP handling includes a delivery server on port 25, a submission server for authenticated clients, and a queue with automatic retries and DKIM signing. IMAP4rev2 implementation provides full mailbox synchronization with CONDSTORE and QRESYNC for efficient offline clients, NOTIFY for multi-mailbox monitoring, MULTISEARCH across mailboxes, and TLS client certificate authentication via the EXTERNAL SASL mechanism. The built-in webmail provides browser-based reading and composing with message threading, attachments, and HTML rendering without requiring a separate web client. Email authentication implements SPF validation, DKIM signing and verification with automatic key rotation, DMARC policy enforcement with aggregate and failure reporting, DANE with DNSSEC-protected TLSA records, and MTA-STS for certificate verification. Junk filtering combines reputation-based sender scoring with Bayesian content analysis trained per account. The web administration interface manages domains, accounts, DNS records, TLS certificates, delivery queue, and real-time log viewing. Internationalized email addresses with EAI and IDNA support handle non-ASCII domains and mailboxes. Account autoconfiguration publishes settings for Thunderbird autoconfig and Outlook autodiscover. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Powering authentication for over 15,000 GitHub stargazers and production deployments across startups and enterprises alike, SuperTokens delivers the complete login infrastructure that Auth0, Firebase Auth, and AWS Cognito charge premium prices for — entirely open source under Apache 2.0 with no per-user limits. The Java-based core service runs as a lightweight HTTP microservice that connects to PostgreSQL or MySQL and handles email-password login, passwordless magic links and OTP via email or SMS, social OAuth with Google, GitHub, Facebook, Apple, and any custom OIDC provider, phone-password authentication, and time-based one-time password multi-factor authentication. Session management uses rotating refresh tokens with anti-CSRF and anti-session-fixation protections, verifying tokens locally in your backend SDK without network round-trips to the core. Frontend SDKs for React, React Native, Angular, Vue, and vanilla JavaScript provide pre-built UI components for login, signup, email verification, and password reset flows, all customizable through an override system that lets you add pre- and post-API logic, custom hooks, and user event handlers. The built-in user management dashboard enables administrators to view users, reset passwords, revoke sessions, modify roles, and manage email verification status. Multi-tenancy and organization support powers B2B SaaS applications with tenant-level authentication configuration and Enterprise SSO via SAML and OIDC. Migration tools support bulk importing millions of existing password hashes, TOTP secrets, and role mappings. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

OpenFGA answers the question 'can this user perform this action on this resource?' in single-digit milliseconds, implementing Google's Zanzibar paper as a production-ready authorization engine adopted by Auth0, Grafana Labs, Canonical, Docker, Agicap, and Read.AI. The server exposes both gRPC and HTTP APIs for authorization queries including Check, ListObjects, ListUsers, Expand, and the high-throughput BatchCheck endpoint that deduplicates and processes multiple authorization decisions in a single request. Authorization models combine relationship-based access control with role-based and attribute-based patterns through a purpose-built DSL that supports contextual tuples, conditional relationship tuples with CEL expressions, and time-based filtering via the ReadChanges API. Storage backends include PostgreSQL 14+, MySQL 8, and SQLite in beta, with an in-memory adapter for development and testing. Official SDKs for Java, .NET, Node.js, Go, and Python provide type-safe client integration, while a Terraform provider enables infrastructure-as-code management of authorization stores and models. The built-in browser playground at port 3000 lets developers visually model authorization schemas, write relationship tuples, and test access control queries interactively before deployment. OpenTelemetry instrumentation integrates with existing monitoring infrastructure, and Helm charts simplify Kubernetes deployment. A VS Code extension provides syntax highlighting and validation for FGA model files, and GitHub Actions automate model testing in CI/CD pipelines. A CNCF incubating project with transparent governance. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

The Bitwarden server, reimplemented in Rust: Vaultwarden (formerly bitwarden_rs) is the unofficial lightweight edition. It speaks the same wire protocol as the official server, so every official Bitwarden client - browser extensions, iOS, Android, desktop, and the bw CLI - connects without modification, while the server itself runs as a single container against SQLite (or MySQL/MariaDB/PostgreSQL) instead of the official multi-container stack that wants gigabytes of RAM. Features Bitwarden gates behind paid tiers ship free: organizations with collections, groups, member roles, and policies; TOTP code storage; file attachments; Bitwarden Send; Emergency Access; event logs; and admin password reset. Two-factor options cover authenticator apps, email, FIDO2 WebAuthn, YubiKey, and Duo, and OIDC-based SSO landed natively in v1.35.0. Zero-knowledge encryption is unchanged - vault data is encrypted client-side and the master password never reaches the server. Attachments and Sends store on local disk or S3-compatible backends, an admin panel manages users and server settings, and backup is copying one data directory. Suited to individuals and teams up to roughly 50 users.

GCHQ open-sourced its "Cyber Swiss Army Knife", and CyberChef became the web app security analysts, incident responders, and CTF players reach for when data needs decoding, decrypting, or dissecting. Its interface is four panes: paste or drag input (files up to 2GB), search a categorized library of hundreds of operations, drag them into a recipe with arguments, and read the output. Operations span Base64, hex, and XOR encoding; AES, DES, and Blowfish encryption; classical ciphers from Caesar to Railfence; hashes and checksums; compression; regex and string extraction of IPs, domains, and URLs; timestamp conversion; and parsers for IPv6, X.509 certificates, and more. Recipes chain arbitrarily - convert from a hexdump then decompress, decrypt AES pulling the IV from the cipher stream, or let the Magic operation auto-detect several layers of nested encoding. Auto Bake re-runs the recipe live as input or arguments change, Step executes one operation at a time for debugging, and flow control (forks, subsections, registers) applies different operations to different parts of the data. Recipes save to files or share as URLs encoding the full pipeline. Crucially, CyberChef is entirely client-side JavaScript - nothing uploads anywhere - and self-hosting guarantees an unmodified copy inside your own network, where malware artifacts belong.

The first container registry to reach CNCF graduated status with over 29,000 GitHub stars since VMware open-sourced it in 2016, Harbor transforms the basic Docker Distribution into a hardened enterprise registry with vulnerability scanning, supply chain signing, multi-datacenter replication, and project-level access control out of the box. Trivy scans every pushed image against the NVD, GitHub Advisory Database, and distribution-specific vulnerability feeds, with scan-on-push policies that block deployment of images exceeding configurable severity thresholds. Artifact signing through Cosign keyless signatures and Notation enforces content trust policies ensuring only cryptographically verified images reach production clusters. Policy-based replication synchronizes images and Helm charts between Harbor instances across multiple datacenters using repository, tag, and label filters with automatic retry and bandwidth throttling — enabling hybrid-cloud and disaster-recovery topologies. The RBAC model isolates projects with per-project quotas, robot accounts for CI/CD automation, webhook notifications, and audit logging that tracks every pull, push, delete, and configuration change. LDAP, Active Directory, and OIDC authentication integrate with existing identity providers, while the proxy cache transparently caches images from Docker Hub, Quay, and other upstream registries to reduce pull latency and rate-limit exposure. The RESTful API with embedded Swagger UI, tag retention policies, garbage collection scheduling, and immutable artifact rules complete the lifecycle management. Deploy via Docker Compose or Helm Chart on Kubernetes. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

With over 34,000 GitHub stars and backing from a well-funded engineering team, Tailscale has fundamentally simplified how developers and system administrators think about secure networking. The client daemon establishes WireGuard tunnels directly between devices using sophisticated NAT traversal techniques, achieving direct peer-to-peer connections in the vast majority of network configurations without requiring port forwarding, firewall rules, or VPN concentrators. When direct connections prove impossible due to restrictive network environments, DERP relay servers provide encrypted fallback paths. MagicDNS assigns human-readable hostnames to every device on the network, eliminating the need to remember IP addresses across a tailnet. Subnet routing allows nodes to advertise access to entire local networks, enabling remote access to office resources, home labs, or cloud VPCs through a single gateway node. Exit node functionality routes all internet traffic through a designated device for privacy protection or geographic flexibility. Access control lists define granular policies for which devices and users can communicate with which services, enforced cryptographically at the network layer. The authentication layer integrates with identity providers including Google, Microsoft, GitHub, Apple, and OIDC-compliant systems for single sign-on access. Taildrop enables direct encrypted file transfers between devices without cloud intermediaries. The tailscale CLI provides complete network management from the terminal including status monitoring, route advertisement, and node configuration. Running Tailscale on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console provides a permanent, always-on node in your mesh network. BSD-3-Clause licensed with an active open-source community.

Engineers who have outgrown Duplicati or rsync scripts tend to appreciate Kopia's design: encrypted, compressed, content-deduplicated snapshots in Go, stored in a repository on any storage you control - S3, Google Cloud Storage, Azure Blob, Backblaze B2, SFTP, WebDAV, or a plain filesystem. Encryption is mandatory and end-to-end: every block is encrypted client-side with AES-256-GCM or ChaCha20-Poly1305 using keys derived from your repository password, and even file names never leave the machine in plaintext. Blocks are packed into 20-40 MB blobs with random names, so the storage provider learns nothing about content or structure. Deduplication is automatic and content-based - identical data across files, snapshots, and even multiple machines backing up to the same repository is stored once. Policies govern everything per-directory: compression choice, retention (hourly through annual), scheduling, and ignore rules. Incremental snapshots are point-in-time records you can mount and browse like a filesystem. This deployment runs the Kopia repository server with its web UI, centralizing backups from multiple client machines over an authenticated API - each client connects with the server URL and certificate fingerprint, and users only see their own snapshots. Error correction, high-latency-tolerant caching, and both CLI and GUI round it out.

With over 24,000 GitHub stars and a rapidly growing community of self-hosters, authentik delivers enterprise-grade identity management that replaces commercial solutions like Okta and Auth0 with a fully self-hosted platform requiring no per-user licensing fees. The platform serves as a unified identity provider supporting SAML 2.0, OAuth 2.0 and OpenID Connect, LDAP for legacy application compatibility, SCIM 2.0 for automated user provisioning, and RADIUS for network device authentication. The visual flow designer enables administrators to create custom authentication workflows combining password verification, multi-factor authentication with TOTP, WebAuthn, and SMS codes, email verification, captcha challenges, and conditional logic based on user attributes or device context. The forward-auth and reverse proxy integration works seamlessly with Traefik, Nginx, Caddy, and Envoy to protect applications that lack built-in authentication. User enrollment flows support self-registration with configurable approval workflows, invitation links, and automatic group assignment. The LDAP outpost exposes user and group data to legacy applications requiring LDAP bind authentication, while the SCIM provider automates user lifecycle management with downstream applications. Multi-tenancy support through brands allows a single authentik instance to serve multiple organizations with independent domains, branding, and authentication policies. The admin interface provides comprehensive user management, group hierarchy, application catalog, event logging with GeoIP enrichment, and system health monitoring. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Licensed under a source-available license with an open-source community edition.

PrivateBin shares text and files with true zero-knowledge encryption: the server stores only ciphertext it cannot decrypt because the key exists exclusively in the URL fragment that never reaches the server. With over 8,400 GitHub stars and 500,000+ Docker pulls, it has become the standard for privacy-respecting paste sharing where not even the hosting operator can read stored content. All encryption uses 256-bit AES in Galois Counter mode performed entirely client-side in the browser. Burn-after-reading mode destroys pastes on first view, while configurable expiration timers automatically purge content after periods ranging from five minutes to forever. Optional password protection adds a second encryption layer requiring recipients to enter a passphrase before decryption occurs. Discussion threads enable anonymous or nickname-based commenting on pastes with IP-based identicon avatars for visual identity. Markdown rendering with live preview formats pastes as styled HTML, and syntax highlighting through prettify.js supports dozens of programming languages across four color themes. File upload support enables sharing images, PDFs, and media files with in-browser preview. QR code generation converts paste URLs for mobile device transfer. Customizable templates include Bootstrap 5, classic Bootstrap CSS, and Darkstrap themes. Storage backends support filesystem, MySQL, PostgreSQL, SQLite, Amazon S3, and Google Cloud Storage. Deploy via Docker with the privatebin/nginx-fpm-alpine image on port 8080. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. zlib licensed.

With 13,800+ GitHub stars and active releases through 2026, Casdoor is the open-source identity platform that ships OAuth 2.0, OIDC, SAML 2.0, CAS, LDAP, SCIM 2.0, WebAuthn passkeys, TOTP multi-factor authentication, and Face ID biometric login in a single Go binary with a React web console — covering every authentication protocol your organization will ever need. Social login connects 50+ identity providers including Google, GitHub, Microsoft Azure AD, Facebook, WeChat, DingTalk, Apple, Twitter, and LinkedIn without custom code. The AI-first architecture includes a Model Context Protocol gateway for AI agent authentication and Agent-to-Agent protocol support for securing LLM-powered workflows. Built-in Casbin integration delivers authorization primitives beyond basic RBAC: attribute-based access control, relationship-based access control, and custom policy models through a unified engine. The organization-scoped multi-tenancy model isolates users, applications, and identity providers per tenant with customizable login pages, branding, and SMTP configuration. SCIM 2.0 endpoints automate user provisioning from HR systems and Active Directory. Official SDKs for Go, Java, Node.js, Python, and PHP accelerate application integration. The RESTful API exposes every resource for programmatic management. Comprehensive audit logs record authentication events and administrative actions. Deploy via Docker Compose with MySQL or PostgreSQL, the all-in-one SQLite Docker image for quick trials, or the official Kubernetes Helm chart for production clusters. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

KrakenD processes over 18,000 requests per second on a single instance while consuming under 50MB of RAM at 1,000 concurrent connections, operating as a stateless API gateway that requires no database whatsoever. The Community Edition has earned over 2,600 GitHub stars by outperforming database-dependent alternatives like Kong and Tyk in independent benchmarks. Written entirely in Go, it uses declarative JSON or YAML configuration files that integrate directly into GitOps workflows for version-controlled infrastructure management. The gateway aggregates responses from multiple backend services into a single API call, transforms request and response payloads with field filtering, grouping, and mapping, and applies zero-trust security policies including JWT validation, OAuth 2.0, CORS, HSTS, clickjacking protection, and XSS prevention. Traffic management features include multi-layer rate limiting at both the router and proxy levels, circuit breakers for backend fault isolation, spike arrest policies, and concurrent call support that requests the same data from multiple backends in parallel for improved response times. Telemetry integrates with OpenTelemetry, Prometheus, Grafana dashboards, Datadog, Zipkin, and Jaeger for distributed tracing and metrics collection. The gateway extends through Go plugins, Lua scripting, Martian modifiers, and Google CEL expressions for custom request processing logic. AI workload routing supports OpenAI, Anthropic, Gemini, and other model endpoints with built-in fallback, retries, and load balancing. Deploy via Docker with the devopsfaith/krakend image as a single binary. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

Encrypted, incremental, compressed backups on storage you already have - Amazon S3, Backblaze B2, Google Drive, Azure, OneDrive, Dropbox, MEGA, Storj, WebDAV, SFTP, FTP, SMB, or a plain local disk - is what the MIT-licensed Duplicati has quietly done for years. Its security model is Trust No One: every block is encrypted with AES-256 (or a local GPG instance) before leaving the machine, and the passphrase never travels, so the storage provider holds only ciphertext. The block-based storage engine gives the best of both backup worlds: after one initial full backup, only changed data blocks upload - modify a tiny part of a huge file and only that part transfers - yet every backup version restores like a full backup in a single operation, with no incremental chains to replay. Deduplication and compression keep remote storage growth slow even across years of versions. A web interface manages everything: the built-in scheduler keeps backups current automatically, flexible filters select folders, file types, or custom patterns, retention policies prune old versions, and an integrated updater flags new releases. On compatible object-lock backends, immutable (WORM) storage protects backup data from ransomware that reaches the credentials. Runs on Windows, macOS, and Linux, free even for commercial use.

Fleet lets IT and security teams query every device in their organization like a SQL database, using osquery to surface installed software, running processes, configurations, and vulnerabilities within seconds across macOS, Windows, Linux, iOS, Android, and ChromeOS. The Go-based server exposes a web console and REST API for centralized device management, with MDM capabilities built on nanoMDM for Apple device enrollment, configuration profiles, and remote lock or wipe. Vulnerability management cross-references installed software inventories against NVD and OVAL CVE databases, automatically flagging known vulnerabilities with severity scores and remediation guidance. Software deployment handles OS updates using Apple Declarative Device Management, Windows Update, and custom installer packages distributed through S3-compatible storage. A GitOps workflow enables infrastructure-as-code management where device policies, osquery queries, and configuration profiles live as YAML files in Git repositories, with CI/CD pipelines pushing changes through the fleetctl CLI. The fleetd agent bundle includes osquery for telemetry, Orbit for version management, and Fleet Desktop providing end users a menu bar status indicator. Integrations connect to Snowflake, Splunk, Elastic, Jira, Zendesk, Vanta, and GitHub Actions for automated compliance reporting. CIS benchmark policies verify security baselines across operating systems. Deployment requires MySQL for persistence and Redis for caching, running as Docker containers or on Kubernetes. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

With 13,800 GitHub stars, adoption by OpenAI for ChatGPT's authentication infrastructure serving 800 million weekly active users, and governance under the Ory open-source ecosystem, Ory Kratos provides enterprise-grade identity management as a headless API server that separates authentication logic from user interface — enabling any frontend framework to consume standardized self-service flows for registration, login, recovery, verification, and profile management. Multi-factor authentication supports passkeys, WebAuthn security keys, TOTP authenticator apps, SMS one-time codes, email magic links, and backup recovery codes with configurable Authenticator Assurance Levels enforcing step-up authentication for sensitive operations. Social sign-in connects to any OpenID Connect provider including Google, GitHub, Apple, and Microsoft, plus enterprise SAML 2.0 federation for B2B single sign-on. Customizable identity schemas using JSON Schema define user profiles with flexible trait structures, while pre- and post-flow webhooks enable integration with CRMs, analytics, and compliance systems. The courier system handles email and SMS delivery for verification codes and password recovery links. Session management provides device tracking, forced logout, and configurable lifespans with privileged session elevation. Deploy alongside Ory Hydra for OAuth2/OIDC token issuance and Ory Keto for fine-grained permissions to build a complete identity platform. Docker Compose deployment with PostgreSQL. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

2FAuth generates TOTP, HOTP, and Steam Guard codes from any web browser, freeing your two-factor authentication from dependence on a single smartphone or app. Lose your phone, switch devices, or sit at a desktop computer, and your 2FA codes remain accessible through the web interface. The Laravel and Vue.js application stores account secrets in an encrypted SQLite database that backs up as a single file. Adding accounts works through camera-based QR scanning or manual secret key entry for services that only provide text codes. Group organization with drag-and-drop sorting keeps large collections navigable, categorized however you prefer. WebAuthn authentication with FIDO2 hardware keys protects vault access with phishing-resistant passwordless login, meaning the tool that secures your accounts is itself secured by the strongest available method. Automatic screen lock triggers after configurable idle time, and OTP obfuscation dots out generated codes until you tap to reveal them, preventing shoulder surfing in shared spaces. The REST API enables browser extensions and external applications to request codes programmatically. Import compatibility with Google Authenticator, Aegis, and 2FAS ensures painless migration without re-enrolling every account from scratch. PWA installation places 2FAuth on your device home screen for native-app-like instant access. Runs on a dedicated RepoCloud VPS with guaranteed resources and full root SSH access. AGPL-3.0 licensed.