Tag: #devops
Writing on GPUs, LLMs, MLOps, Kubernetes — and mindset · 193 posts
OpenID Connect Deep Dive — From the Authorization Code Flow to Discovery
A protocol-level dissection of how OIDC stacks an authentication layer on top of OAuth 2.0: the role differences between ID Token, Access Token, and Refresh Token, and the detailed Authorization Code + PKCE flow with rea
2026-06-12 · 14 min read #oidc#oauth2#jwt#sso#securityAnatomy of npm Supply Chain Attacks — Defense Strategies for the Era When Even Red Hat Got Hit
Triggered by the June 2026 incident in which even official Red Hat Cloud Services npm packages were exposed to malicious code, this post dissects the types of npm supply chain attacks and lays out the defense stack organ
2026-06-12 · 17 min read #npm#supply-chain#security#devops#sigstoreCustomizing Keycloak Tokens — Protocol Mappers and Claims Design in Practice
A hands-on guide to designing JWT claims with Keycloak Protocol Mappers and Client Scopes. Covers built-in mappers, a custom ProtocolMapper SPI implementation, audience validation pitfalls, token bloat diet strategies, a
2026-06-12 · 15 min read #keycloak#oidc#jwt#sso#securityKeycloak Observability — Metrics, Audit Logs, and Event-Driven Monitoring
A comprehensive guide to Keycloak observability: the event system and metrics endpoint, shipping events externally with the EventListener SPI, building Prometheus and Grafana dashboards, OpenTelemetry tracing, anomaly de
2026-06-12 · 13 min read #keycloak#observability#monitoring#prometheus#securityKeycloak 26 Architecture Deep Dive — Understanding Realms, Clients, and the Quarkus Runtime
A deep dive into the internal architecture of Keycloak 26.x. We cover the WildFly-to-Quarkus transition, the realm/client/role domain model, the authentication flow engine, kc.sh build optimization, and the new features
2026-06-12 · 16 min read #keycloak#sso#oidc#security#devopsFAPI 2.0 — A Complete Guide to the Financial-grade API Security Profile
A thorough walkthrough of FAPI 2.0 Security Profile, the standard of the open banking and open data era. Covers the simplification from FAPI 1.0 to 2.0, the core requirements of PAR, PKCE, and sender-constrained tokens,
2026-06-12 · 15 min read #fapi#oauth2#oidc#keycloak#securityZero Trust and Identity-Aware Proxy — Building the BeyondCorp Model Yourself
The perimeter is dead and identity-first security is the new default. This post walks through the core of the Google BeyondCorp papers and builds an Identity-Aware Proxy from scratch with oauth2-proxy and Keycloak. We co
2026-06-12 · 18 min read #zero-trust#iap#beyondcorp#oauth2-proxy#keycloakRefresh Token Rotation and Session Management — Designing a Theft-Resistant Token Lifecycle
From access/refresh token lifetime design principles to rotation, reuse detection, and token family invalidation — we design a token lifecycle that assumes theft. We cover the three-layer model of IdP, app, and SSO sessi
2026-06-12 · 16 min read #oauth2#session#keycloak#security#ssoSSO Fundamentals — SAML vs OAuth 2.0 vs OIDC, What to Use and When
A complete walkthrough of how SSO works (IdP/SP/RP), sessions vs tokens, and the history and role differences of SAML, OAuth 2.0, and OIDC. Includes a protocol decision tree, comparison tables, and real authentication fl
2026-06-12 · 18 min read #sso#saml#oauth2#oidc#iamOAuth 2.1 Migration Guide — Designing Authentication in the Era of Mandatory PKCE
A deep dive into the known weaknesses of OAuth 2.0 and how the OAuth 2.1 draft consolidates RFC 6749, RFC 7636, and RFC 9700 into a single spec. We cover why Implicit and ROPC were removed, how PKCE works, refresh token
2026-06-12 · 17 min read #oauth2#oidc#security#pkce#ssoDissecting Symantec SiteMinder Architecture — The Standard of Legacy Enterprise WebSSO
A deep dive into SiteMinder, the product that dominated enterprise WebSSO for over two decades. We dissect the Policy Server, Web Agent, SMSESSION cookie, the realm/rule/policy object model, and the security implications
2026-06-12 · 17 min read #siteminder#sso#iam#security#webssoSAML 2.0 Deep Dive — Mastering Assertions, Bindings, and Metadata
A dissection of SAML 2.0 with real XML examples: the structure of the Assertion at its heart, the AuthnRequest/Response flow, SP-initiated vs IdP-initiated SSO, HTTP-Redirect/POST/Artifact bindings, metadata exchange, an
2026-06-12 · 13 min read #saml#sso#xml#security#iamKeycloak SPI Extension Development — From Custom Authenticators to EventListeners
A complete guide to developing Keycloak SPI (Service Provider Interface) extensions. We cover the Provider/ProviderFactory architecture, a full internal SMS OTP Authenticator implementation, a Kafka audit-log EventListen
2026-06-12 · 13 min read #keycloak#spi#java#security#devopsKeycloak Identity Brokering — From Social Login to External IdP Federation
A practical guide to building Google/GitHub/Apple social login and external SAML/OIDC IdP federation with Keycloak Identity Brokering. Covers the first broker login flow, account linking with duplicate emails, attribute
2026-06-12 · 15 min read #keycloak#sso#oidc#saml#identity-brokeringOAuth Token Exchange (RFC 8693) — The Definitive Guide to Delegation and Propagation in Microservices
How to solve the token propagation problem between microservices with RFC 8693 Token Exchange. Covers the difference between impersonation and delegation, request and response parameters, standard support in Keycloak 26.
2026-06-12 · 15 min read #oauth2#keycloak#oidc#security#microservicesKeycloak + Spring Security 6 Integration — Resource Server and OAuth2 Client in Practice
A practical guide to integrating Keycloak with Spring Security 6 as an OAuth2 Resource Server and Client. Covers issuer-uri auto-configuration, mapping realm and client roles with JwtAuthenticationConverter, OIDC logout,
2026-06-12 · 11 min read #keycloak#spring-security#oauth2#oidc#jwtKeycloak LDAP/Active Directory Integration — A Practical Guide to User Federation
A hands-on guide to integrating LDAP and Active Directory with Keycloak User Federation, from architecture to production settings. Covers edit modes and sync strategies, AD-specific configuration, attribute mappers, perf
2026-06-12 · 21 min read #keycloak#ldap#active-directory#sso#securityAdvanced OAuth Flows — When You Need CIBA, Device Flow, and DPoP
A guide to advanced OAuth mechanisms for authentication scenarios that the standard redirect flow cannot solve. Covers the Device Authorization Grant (RFC 8628), CIBA with its poll/ping/push modes, the DPoP (RFC 9449) pr
2026-06-12 · 15 min read #oauth2#oidc#keycloak#ciba#dpopKeycloak HA on Kubernetes — Infinispan Clustering and Zero-Downtime Deployments
A hands-on guide to running Keycloak with high availability on Kubernetes. We compare the Operator and Helm, walk through Infinispan caches and JGroups DNSPING, persistent user sessions, the 26.6 zero-downtime rolling pa
2026-06-12 · 13 min read #keycloak#kubernetes#infinispan#ha#devopsMastering JWT Security — Signature Verification, Key Rotation, and Common Vulnerabilities
We dissect the structure of JWT, JWS, and JWE and cover real-world vulnerabilities such as alg confusion attacks and kid injection, along with their defenses. From JWKS-based key rotation and algorithm selection includin
2026-06-12 · 16 min read #jwt#security#oidc#keycloak#cryptography