tools.html

<!DO
    <li>
      <a href="https://releaserun.com/linux-signal-reference/" target="_blank">Linux Signal Reference &amp; Kill Command Builder</a>
      — Complete reference for all 31 Linux signals with interactive kill command builder. SIGTERM, SIGKILL, SIGHUP explained with generated commands for PID, process name, port, and pgrep.
    </li>
    <li>
      <a href="https://releaserun.com/package-version-checker/" target="_blank">Package Version Checker</a>
      — Check if your npm, PyPI, crates.io, or RubyGems package is outdated. Enter package name and current version to see the version gap (patch/minor/major), days since latest release, and changelog links.
    </li>
    <li>
      <a href="https://releaserun.com/jwt-inspector/" target="_blank">JWT Token Inspector</a>
      — Decode and debug JSON Web Tokens instantly. See header, payload, all claims with descriptions, expiry countdown, and algorithm badge. 100% client-side — your token never leaves your browser.
    </li>
    <li>
      <a href="https://releaserun.com/github-release-tracker/" target="_blank">GitHub Release Tracker</a>
      — View releases and changelogs for any public GitHub repository. Shows semver gap type (major/minor/patch), rendered markdown changelogs, repo metadata, and release history. Supports optional GitHub token for higher rate limits.
    </li>
    <li>
      <a href="https://releaserun.com/semver-range-tester/" target="_blank">Semver Range Tester</a>
      — Test whether a version satisfies a semver range. Supports ^, ~, >=, &lt;, *, ||, and hyphen ranges with npm/node-semver semantics. Batch test multiple versions at once. Includes full range syntax reference.
    </li>
    <li>
      <a href="https://releaserun.com/uptime-sla-calculator/" target="_blank">Uptime SLA Calculator</a>
      — Translate SLA percentages into real downtime. 99.9% = 8.7h/year. Includes downtime budget planner (enter incident frequency + duration), actual availability back-calculator, and industry comparison table with grades.
    </li>
    <li>
      <a href="https://releaserun.com/http-security-headers/" target="_blank">HTTP Security Headers Reference</a>
      — Every HTTP security header: HSTS, CSP, X-Frame-Options, Referrer-Policy, COOP, CORP, CORS, Permissions-Policy and more. Risk ratings, nginx config snippets, browser support, filter by critical/recommended/situational.
    </li>
    <li>
      <a href="https://releaserun.com/kubernetes-resource-types/" target="_blank">Kubernetes Resource Types Reference</a>
      — Every K8s object explained with YAML examples: Pod, Deployment, StatefulSet, DaemonSet, Job, CronJob, Service, Ingress, NetworkPolicy, ConfigMap, Secret, HPA, VPA, PDB, RBAC, and more. Category filter + search.
    </li>
    <li>
      <a href="https://releaserun.com/dns-record-types/" target="_blank">DNS Record Types Reference</a>
      — Every DNS record type explained: A, AAAA, CNAME, MX, TXT, NS, SOA, PTR, SRV, CAA, SPF, DKIM, DMARC, HTTPS, TLSA and more. Includes record format examples, dig commands, TTL recommendations, and gotchas.
    </li>
    <li>
      <a href="https://releaserun.com/port-reference/" target="_blank">Well-Known Ports Reference</a>
      — TCP and UDP port numbers for 60+ common services: SSH 22, HTTP 80, HTTPS 443, MySQL 3306, PostgreSQL 5432, Redis 6379, Kubernetes 6443 and more. Sortable table, category filter, exact port search, and diagnostic commands (ss, lsof, nmap).
    </li>
    <li>
      <a href="https://releaserun.com/chmod-calculator/" target="_blank">chmod Calculator</a>
      — Interactive Linux file permissions builder. Click bits to build octal codes or enter octal to see permissions. Includes setuid/setgid/sticky bits, symbolic chmod examples, and common permissions reference (755, 644, 700, 1777 etc.).
    </li>
    <li>
      <a href="https://releaserun.com/http-status-codes/" target="_blank">HTTP Status Codes Reference</a>
      — Complete guide to all HTTP status codes: 1xx informational, 2xx success, 3xx redirects, 4xx client errors, 5xx server errors. Expandable cards with when-to-use, common misuses (401 vs 403, 302 vs 307, 502 vs 503 vs 504), and example responses.
    </li>
    <li>
      <a href="https://releaserun.com/curl-reference/" target="_blank">curl Command Reference</a>
      — 30+ curl flags with copy-ready examples: POST JSON, Bearer token, file upload, follow redirects, save response, status code checks, retry, timeout, mTLS, and proxy. Filterable by category.
    </li>
    <li>
      <a href="https://releaserun.com/jq-reference/" target="_blank">jq Reference</a>
      — 40+ jq filters and real-world recipes: map/select/sort_by/group_by, to_entries/with_entries, string operations, conditionals, curl+jq patterns, kubectl+jq, CSV output, and JSON file processing.
    </li>
    <li>
      <a href="https://releaserun.com/github-actions-reference/" target="_blank">GitHub Actions Reference</a>
      — 35+ workflow patterns: on: events, job matrix, outputs, reusable workflows, expressions and contexts (github/env/secrets/steps), conditions, caching, Docker push, environments with approval gates, and composite actions.
    </li>
    <li>
      <a href="https://releaserun.com/sql-reference/" target="_blank">SQL Quick Reference</a>
      — 35+ SQL patterns: all JOINs, GROUP BY, window functions (ROW_NUMBER/LAG/running totals), CTEs, WITH RECURSIVE, ON CONFLICT upsert, RETURNING, indexes, EXPLAIN ANALYZE, and PostgreSQL features (JSONB, generate_series, COPY).
    </li>
    <li>
      <a href="https://releaserun.com/docker-reference/" target="_blank">Docker Commands Reference</a>
      — 35+ Docker commands: docker run (volumes, ports, limits), multi-stage builds, .dockerignore, docker compose, container debugging (exec/logs/stats), image management, networks, health checks, and optimization recipes.
    </li>
    <li>
      <a href="https://releaserun.com/git-reference/" target="_blank">Git Commands Reference</a>
      — 35+ Git commands: interactive rebase (squash/fixup/drop), cherry-pick, stash with names, reflog recovery, bisect, reset (soft/mixed/hard), revert, restore, force-with-lease push, and aliases.
    </li>
    <li>
      <a href="https://releaserun.com/bash-reference/" target="_blank">Bash Scripting Reference</a>
      — 35+ Bash patterns: set -euo pipefail, arrays (indexed+associative), string manipulation, conditions ([[ ]]), loops, functions, getopts, heredoc, trap cleanup, retry with backoff, parallel execution, and full script template.
    </li>
    <li>
      <a href="https://releaserun.com/openssl-reference/" target="_blank">OpenSSL Commands Reference</a>
      — 30+ OpenSSL commands: inspect certs (x509 -text/-dates/-fingerprint), check expiry from live servers (s_client), generate RSA/ECDSA keys, CSR with SANs, PEM/DER/PFX conversion, debug TLS errors, DH params, expiry monitoring script.
    </li>
    <li>
      <a href="https://releaserun.com/grep-sed-awk-reference/" target="_blank">grep, sed &amp; awk Reference</a>
      — 35+ patterns: grep (recursive, context lines, regex, -F fixed string, -l/-L), sed (substitution, in-place -i, delete/insert), awk (print columns, field separator, BEGIN/END, aggregation, deduplication, log analysis pipelines).
    </li>
    <li>
      <a href="https://releaserun.com/regex-reference/" target="_blank">Regex Reference</a>
      — Character classes (\d \w \s), custom [a-z] sets, anchors (^ $ \b), greedy vs lazy quantifiers, capturing/non-capturing groups, named groups, lookahead/lookbehind, flags (i/g/m/s/x), and real-world patterns (email, IPv4, UUID, semver, JWT, slug).
    </li>
    <li>
      <a href="https://releaserun.com/python-packaging-reference/" target="_blank">Python Packaging Reference</a>
      — venv, uv (10-100x faster), pip install/freeze/pip-tools, pyproject.toml (PEP 517/621, ruff/mypy/pytest config), Poetry, Conda, publishing to PyPI (twine, Trusted Publishers), versioning, src vs flat layout.
    </li>
    <li>
      <a href="https://releaserun.com/vim-reference/" target="_blank">vim / Neovim Reference</a>
      — :w/:q/:wq/:q!/ZZ, mode switching, hjkl+word+line movement, operator+motion grammar (d/c/y + text objects iw/di"/dat), :%s substitute, macros (q{reg} @a), named/clipboard registers, Ctrl+w splits, tabs, buffers, marks, folding, .vimrc/init.lua essentials.
    </li>
    <li>
      <a href="https://releaserun.com/tmux-reference/" target="_blank">tmux Reference</a>
      — Sessions (attach/detach/scripted setup), windows (prefix c/n/p), panes (split/zoom/resize), copy mode (vi keys, clipboard), ~/.tmux.conf (Ctrl+a remap, mouse on, vi copy), SSH+tmux persistent session pattern.
    </li>
    <li>
      <a href="https://releaserun.com/go-reference/" target="_blank">Go Reference</a>
      — go mod init/tidy, go get versions, go mod replace/vendor, go build -ldflags (version injection), cross-compilation (GOOS/GOARCH/CGO_ENABLED=0 for static binary), go test -race -cover -bench pprof, go install tools, GOPROXY/GOPRIVATE, go work workspace, //go:build tags.
    </li>
    <li>
      <a href="https://releaserun.com/npm-reference/" target="_blank">npm / Node.js Reference</a>
      — npm install/ci, package.json scripts (pre/post hooks, local .bin PATH), npx, npm version/publish/audit, .npmrc (private registry, save-exact), nvm/fnm/volta, npm workspaces monorepo.
    </li>
    <li>
      <a href="https://releaserun.com/kubectl-reference/" target="_blank">kubectl Reference</a>
      — kubectl get (all namespaces, labels, short names), apply/delete, logs (-f/--previous/-l selector), exec -it, rollout (status/undo/restart), scale/HPA, describe Events debugging, kubectx/kubens, jsonpath/-o formats, port-forward.
    </li>
    <li>
      <a href="https://releaserun.com/terraform-reference/" target="_blank">Terraform Reference</a>
      — terraform init (-backend-config, .lock.hcl), fmt/validate, plan -out=tfplan, apply -auto-approve, state mv/rm/import, workspaces, TF_VAR_* secrets, modules (~> version), S3+DynamoDB backend.
    </li>
    <li>
      <a href="https://releaserun.com/cargo-reference/" target="_blank">Cargo &amp; Rust Reference</a>
      — cargo build (--release, musl cross-compile), cargo check (2-5x faster), Cargo.toml (features, profiles), cargo test (--nocapture, Criterion benchmarks), clippy (-D warnings CI), cargo publish, workspace.dependencies.
    </li>
    <li>
      <a href="https://releaserun.com/makefile-reference/" target="_blank">Makefile Reference</a>
      — .PHONY, self-documenting help target (## comments), := vs = vs ?= variables, automatic variables ($@ $&lt; $^ $*), pattern rules (%.o: %.c), wildcard/patsubst, ifeq, $(MAKE) sub-makes, Go/Python/Node.js recipes.
    </li>
    <li>
      <a href="https://releaserun.com/typescript-reference/" target="_blank">TypeScript Reference</a>
      — tsconfig.json (strict, noUncheckedIndexedAccess, paths aliases), type utilities (Partial/Pick/Omit/ReturnType/Awaited), generics, type guards (is/asserts/never exhaustiveness), discriminated unions, satisfies (TS 4.9), as const.
    </li>
    <li>
      <a href="https://releaserun.com/postgresql-reference/" target="_blank">PostgreSQL &amp; psql Reference</a>
      — psql meta-commands (\d \dt \x auto \timing \copy \watch), pg_stat_activity queries, pg_blocking_pids locks, EXPLAIN ANALYZE, VACUUM FULL vs pg_repack, pg_dump -Fc parallel restore, ALTER DEFAULT PRIVILEGES, CREATE INDEX CONCURRENTLY.
    </li>
    <li>
      <a href="https://releaserun.com/redis-reference/" target="_blank">Redis Reference</a>
      — SCAN vs KEYS (never KEYS in prod), SET NX EX, INCR counters, BLPOP queues, HSET/HGETALL, ZADD leaderboards, SUBSCRIBE/PUBLISH, MULTI/EXEC/WATCH, FLUSHDB warning, cache/rate-limit/distributed-lock patterns.
    </li>
    <li>
      <a href="https://releaserun.com/nginx-reference/" target="_blank">Nginx Configuration Reference</a>
      — server blocks, location priority (=/^~/~/prefix), proxy_pass (WebSocket, path stripping), upstream (least_conn/ip_hash/max_fails/keepalive), SSL/TLS (TLSv1.3, OCSP, HSTS), rate limiting (limit_req burst nodelay), gzip, proxy_cache, JSON logs.
    </li>
    <li>
      <a href="https://releaserun.com/docker-compose-reference/" target="_blank">Docker Compose Reference</a>
      — compose.yaml v2, depends_on (service_healthy/started/completed), healthcheck (pg_isready/redis-cli ping), named volumes vs bind mounts :ro vs tmpfs, networks internal:true, profiles for optional services, Docker secrets /run/secrets/, resource limits, docker compose up/down/logs/exec/run/config, override files.
    </li>
    <li>
      <a href="https://releaserun.com/linux-admin-reference/" target="_blank">Linux Admin &amp; Debugging Reference</a>
      — ps aux/pgrep -a, df -h vs df -i inodes, du/sort, ss -tlnp (not netstat), lsof port+deleted-files footgun, ip addr/route, systemctl enable --now + custom .service unit, journalctl -f/--since/--no-pager, strace -p -e trace=network/file -c summary (safe on prod), OOM killer dmesg, perf top.
    </li>
    <li>
      <a href="https://releaserun.com/kubernetes-yaml-reference/" target="_blank">Kubernetes YAML Reference</a>
      — Deployment (maxUnavailable:0, probes, resource limits, topologySpread), Service types (ClusterIP/LoadBalancer/Headless/ExternalName), StatefulSet volumeClaimTemplates, CronJob, ConfigMap/Secret (stringData, envFrom, volumeMount), PVC reclaimPolicy:Retain, Ingress TLS+cert-manager, HPA v2, PodDisruptionBudget, RBAC (automountServiceAccountToken:false, resourceNames), NetworkPolicy default-deny-all.
    </li>
    <li>
      <a href="https://releaserun.com/helm-reference/" target="_blank">Helm Reference</a>
      — helm upgrade --install (idempotent CI pattern), --atomic auto-rollback, rollback by revision, repo add/update/search, show values, pull --untar, template + dry-run validation; --set vs -f values (multiple files merge), --set-string type safety, --set key=null remove; toYaml+nindent, required, default, include _helpers.tpl, checksum annotation for ConfigMap-triggered restarts; pre-upgrade hooks for DB migrations, helm lint --strict, helm get manifest.
    </li>
    <li>
      <a href="https://releaserun.com/aws-cli-reference/" target="_blank">AWS CLI Reference</a>
      — configure/SSO/profiles, get-caller-identity, --query JMESPath, S3 sync/presign/--delete, EC2 describe+SSM session (no SSH needed), IAM assume-role+simulate-principal-policy, EKS update-kubeconfig, ECR login+push, Lambda invoke+deploy, SSM Parameter Store SecureString hierarchy, CloudWatch logs tail --follow.
    </li>
    <li>
      <a href="https://releaserun.com/pytest-reference/" target="_blank">pytest Reference</a>
      — -v/-k/-x/--lf/--pdb flags, assert rewriting + pytest.raises/approx, conftest.py scope (function/class/module/session), yield teardown, autouse, tmp_path/capsys builtins; parametrize (pytest.param id=), skip/skipif/xfail; patch decorator/context manager (patch where used not defined), side_effect, assert_called_once_with; monkeypatch.setenv/setattr/chdir; pytest-cov --cov-fail-under, --cov-branch, pragma: no cover.
    </li>
    <li>
      <a href="https://releaserun.com/asyncio-reference/" target="_blank">Python asyncio Reference</a>
      — async def vs await, asyncio.run(), gather (order preserved, return_exceptions), create_task, TaskGroup 3.11+, Semaphore concurrency limit; timeout/wait_for/shield, retry backoff; to_thread for sync libs (never time.sleep in async!); aiohttp one-session pattern, aiofiles; Queue producer/consumer with task_done+join, Lock rate limiter, Semaphore N-concurrent, Event signaling.
    </li>
    <li>
      <a href="https://releaserun.com/gh-cli-reference/" target="_blank">GitHub CLI (gh) Reference</a>
      — auth login/GH_TOKEN/CI usage; pr create (--fill/--draft), checkout one command, review, merge squash/--auto, checks --watch --exit-status; issue create/list (@me/labels/search cross-repo), run watch (--exit-status blocks CI), view --log-failed (only failed steps), workflow dispatch + inputs; repo fork (--clone --remote), release create (--generate-notes auto from PRs); gh api REST+GraphQL --paginate --jq.
    </li>
    <li>
      <a href="https://releaserun.com/react-hooks-reference/" target="_blank">React Hooks Reference</a>
      — useState (functional updates prev=>, lazy init, object spread, array patterns); useEffect (deps array, cleanup, async inner function + cancelled flag + AbortController, stale closure trap); useCallback+useMemo (only useful with memo() child, profile first); useRef (DOM access, timer IDs no re-render, previous value, stable callback via ref); useContext provider + useMemo value, useReducer for complex state; custom hooks (useLocalStorage, useDebounce, useFetch, useEventListener).
    </li>
    <li>
      <a href="https://releaserun.com/gcloud-reference/" target="_blank">GCP CLI (gcloud) Reference</a>
      — auth login/ADC/config configurations (named profiles); compute instances list/ssh/scp/create/firewall-rules; Cloud Run deploy (--set-secrets, --min-instances, update-traffic canary splits), jobs; GKE get-credentials/create-auto/Artifact Registry push/Workload Identity; IAM add-iam-policy-binding/service-accounts/impersonate; Secret Manager versions access; logging tail+read; Cloud Storage rsync --delete-unmatched, gcloud storage vs gsutil.
    </li>
    <li>
      <a href="https://releaserun.com/go-testing-reference/" target="_blank">Go Testing Reference</a>
      — go test -race (always in CI), -run regex subtests, -cover/-count flaky detection; table-driven tests []struct + t.Run (tt := tt capture, Go 1.22+ fixed); testify require (stops) vs assert (continues), require.Eventually; t.Helper() caller line numbers, t.Cleanup() (better than defer for parallel subtests), TestMain global setup; benchmarks b.ResetTimer/ReportAllocs/RunParallel, benchstat comparison; fuzz Go 1.18+ f.Add seeds + invariant testing; httptest.NewRecorder vs NewServer.
    </li>
    <li>
      <a href="https://releaserun.com/python-type-hints-reference/" target="_blank">Python Type Hints & Dataclasses</a>
      — @dataclass (field default_factory mutable default bug, frozen+hashable, KW_ONLY, slots, __post_init__ validation+derived), asdict/replace/InitVar; TypedDict, Protocol (structural subtyping, runtime_checkable), Literal, Final, Union |; TypeVar+Generic (Stack[int]), Annotated (Pydantic/FastAPI), @overload multiple signatures, TypeGuard narrowing; Python 3.12 type aliases, Self builder pattern, Never exhaustiveness, ParamSpec typed decorators.
    </li>
    <li>
      <a href="https://releaserun.com/kubernetes-troubleshooting/" target="_blank">Kubernetes Troubleshooting</a>
      — CrashLoopBackOff (--previous logs, exit codes: 137=OOMKilled/1=app error/0=wrong CMD, startupProbe vs liveness); OOMKilled (kubectl top, requests vs limits, JVM -Xmx 70%); Pending (Events section, node resources, taints, PVC unbound); ImagePullBackOff (wrong tag, imagePullSecrets, ECR 12h expiry, rate limits); Service no-endpoints=selector mismatch; NetworkPolicy blocking; kubectl debug ephemeral container (netshoot).
    </li>
    <li>
      <a href="https://releaserun.com/dockerfile-best-practices/" target="_blank">Dockerfile Best Practices</a>
      — Multi-stage (Go 800MB→12MB, Node 1.2GB→180MB, Python wheel); layer cache order (deps before source, --mount=type=cache); .dockerignore (node_modules, .git, .env); non-root (--chown COPY, distroless nonroot, K8s SecurityContext); secrets (never ENV/ARG, BuildKit --mount=type=secret); base images (scratch/distroless/alpine/slim, pin @sha256); ENTRYPOINT exec form PID 1 signals; HEALTHCHECK; readOnlyRootFilesystem; Trivy in CI.
    </li>
    <li>
      <a href="https://releaserun.com/rust-error-handling-reference/" target="_blank">Rust Error Handling</a>
      — Result (map/map_err/and_then/unwrap_or/collect fail-fast), Option (as_deref/flatten/zip/take), ? operator (desugars to match+From::from), thiserror (#[from] auto-converts #[error(...)] Display), anyhow (context/bail!/ensure!/anyhow!, {:?} full chain), custom error types (impl Error source() for chains), panic vs Result (bug=panic, expected failure=Result, expect() over unwrap()).
    </li>
    <li>
      <a href="https://releaserun.com/azure-cli-reference/" target="_blank">Azure CLI (az) Reference</a>
      — az login (browser/device-code/service-principal/managed identity), az configure --defaults; VM (create/SSH/run-command without SSH/deallocate vs stop/resize/open-port); AKS (get-credentials/nodepool/autoscaler/upgrade/attach-acr); Storage (blob upload-batch/generate-sas/static-website); Key Vault (RBAC mode/managed identity access); RBAC + service principals (federated credentials OIDC, no client secret).
    </li>
    <li>
      <a href="https://releaserun.com/ssh-reference/" target="_blank">SSH Reference</a>
      — 30+ SSH patterns: config file (Host blocks, ProxyJump, ServerAliveInterval), ssh-keygen Ed25519, ssh-agent, local/remote/SOCKS port forwarding (-L/-R/-D), ProxyJump bastion hosts, rsync, sshd_config hardening.
    </li>
    <li>
      <a href="https://releaserun.com/ssh-reference/" target="_blank">SSH Reference</a>
      — 30+ SSH patterns: config file (Host blocks, ProxyJump, ServerAliveInterval), key management (ssh-keygen Ed25519, ssh-agent, ForwardAgent), local/remote/SOCKS port forwarding (-L/-R/-D), ProxyJump bastion hosts, rsync over SSH, sshd_config hardening, troubleshooting with -v.
    </li>
    <li>
      <a href="https://releaserun.com/developer-reference-tools/" target="_blank">Developer Reference Tools Hub</a>
      — Directory of all developer cheatsheets and reference tools: chmod, DNS records, HTTP security headers, Kubernetes resources, Linux signals, ports, semver, SLA calculator and more.
    </li>CTYPE html>
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    <h1>Free Developer Tools</h1>
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  <!-- SECURITY & VULNERABILITY -->
  <h2 class="section-title">Security &amp; Vulnerability</h2>
  <p class="section-sub">Find and fix security issues in your stack</p>
  <div class="tools-grid">
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/vulnerability-scanner/">Dependency Vulnerability Scanner</a></h3>
      <p>Upload package.json, requirements.txt, go.mod, or any lockfile. Get a full CVE report with severity scores and fix versions.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">SCA</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/env-security-scanner/">.env Security Scanner</a></h3>
      <p>Detect leaked secrets, weak credentials, and insecure patterns in your environment files.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">Secrets</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/dockerfile-linter/">Dockerfile Security Linter</a></h3>
      <p>Static analysis for Dockerfiles. Catches security misconfigurations, inefficient layers, and best practice violations.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">Docker</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/cve-dashboard/">CVE Dashboard</a></h3>
      <p>Monitor known vulnerabilities across your entire stack. Real-time data from multiple CVE databases.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">Monitoring</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/header-analyzer/">Security Header Analyzer</a></h3>
      <p>Check any URL for missing or misconfigured security headers. CSP, HSTS, X-Frame-Options, and more.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">Headers</span></div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/cve-alerting-dashboard/">CVE Alerting Dashboard</a></h3>
      <p>Configure your tech stack, track CVEs in real-time with EPSS exploit probability scores, and set up automated alerts.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">Monitoring</span><span class="tag">Alerts</span></div>
    </div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/ssl-checker/">SSL/TLS Certificate Analyzer</a></h3>
      <p>Deep analysis of SSL certificates. Check expiry, chain validity, cipher suites, and protocol support.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">SSL</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/ssl-config-generator/">SSL/TLS Config Generator</a></h3>
      <p>Generate secure SSL/TLS configs for Nginx, Apache, Caddy, HAProxy, and Traefik. Based on Mozilla guidelines.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag tag-devops">Web Servers</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/jwt-decoder/">JWT Decoder &amp; Inspector</a></h3>
      <p>Decode, inspect, and validate JSON Web Tokens with security analysis and expiration tracking. Client-side only.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">JWT</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/sbom-analyzer/">SBOM Health Analyzer</a></h3>
      <p>Analyze Software Bill of Materials for license risks, outdated components, and supply chain vulnerabilities.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">SBOM</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/actions-auditor/">GitHub Actions Auditor</a></h3>
      <p>Security audit for GitHub Actions workflows. Detects unpinned actions, secret leaks, and privilege escalation risks.</p>
      <div class="tags"><span class="tag tag-security">Security</span><span class="tag">CI/CD</span></div>
    </div>
  </div>

  <!-- KUBERNETES -->
  <h2 class="section-title">Kubernetes</h2>
  <p class="section-sub">Tools for K8s cluster management and upgrades</p>
  <div class="tools-grid">
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/k8s-upgrade-simulator/">K8s Upgrade Simulator</a></h3>
      <p>Plan your cluster upgrade path. See API deprecations, breaking changes, and required actions at each step.</p>
      <div class="tags"><span class="tag tag-k8s">Kubernetes</span><span class="tag">Upgrades</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/k8s-deprecation-checker/">K8s Deprecation Checker</a></h3>
      <p>Check your manifests for deprecated or removed API versions. Catches issues before they break your cluster.</p>
      <div class="tags"><span class="tag tag-k8s">Kubernetes</span><span class="tag">APIs</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.github.io/k8s-deprecated-apis.html">K8s Deprecated APIs Cheat Sheet</a></h3>
      <p>Quick reference: every deprecated K8s API from 1.16 to 1.32+, when it was removed, and what to migrate to. Searchable and filterable.</p>
      <div class="tags"><span class="tag tag-k8s">Kubernetes</span><span class="tag">Reference</span><span class="tag">APIs</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/k8s-cost-estimator/">K8s Cost Estimator</a></h3>
      <p>Estimate infrastructure costs for your Kubernetes workloads across AWS EKS, GCP GKE, and Azure AKS.</p>
      <div class="tags"><span class="tag tag-k8s">Kubernetes</span><span class="tag">Cost</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/k8s-rbac-generator/">K8s RBAC Policy Generator</a></h3>
      <p>Wizard-based least-privilege RBAC YAML generator for Kubernetes roles and bindings.</p>
      <div class="tags"><span class="tag tag-k8s">Kubernetes</span><span class="tag tag-security">Security</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/k8s-resource-calculator/">K8s Resource Calculator</a></h3>
      <p>Calculate CPU/memory requests, node sizing, and cost estimation for Kubernetes workloads.</p>
      <div class="tags"><span class="tag tag-k8s">Kubernetes</span><span class="tag">Resources</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/helm-checker/">Helm Chart Compatibility</a></h3>
      <p>Check Helm chart compatibility with your Kubernetes version. Validates API versions and dependencies.</p>
      <div class="tags"><span class="tag tag-k8s">Kubernetes</span><span class="tag">Helm</span></div>
    </div>
  </div>

  <!-- DOCKER & CONTAINERS -->
  <div class="tools-grid">
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/docker-tag-explorer/">Docker Tag Explorer</a></h3>
      <p>Browse Docker Hub image tags, compare sizes by architecture, filter and sort. Get pull commands instantly.</p>
      <div class="tags"><span class="tag tag-devops">Docker</span><span class="tag">Tags</span></div>
    </div>
  </div>

  <!-- DEVOPS & INFRASTRUCTURE -->
  <h2 class="section-title">DevOps &amp; Infrastructure</h2>
  <p class="section-sub">CI/CD, containers, and infrastructure tools</p>
  <div class="tools-grid">
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/terraform-provider-matrix/">Terraform Provider Matrix</a></h3>
      <p>Check which provider versions work with your Terraform release. 12 major providers covered.</p>
      <div class="tags"><span class="tag tag-devops">Terraform</span><span class="tag">Compatibility</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/terraform-checker/">Terraform Provider Checker</a></h3>
      <p>Validate Terraform provider versions and check for updates across your infrastructure code.</p>
      <div class="tags"><span class="tag tag-devops">Terraform</span><span class="tag">Validation</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/container-image-size-optimizer/">Container Image Optimizer</a></h3>
      <p>Analyze your Docker images and get actionable recommendations to reduce image size.</p>
      <div class="tags"><span class="tag tag-devops">Docker</span><span class="tag">Optimization</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/container-image-picker/">Container Base Image Picker</a></h3>
      <p>Compare base images by size, security, and features. Find the right starting point for your containers.</p>
      <div class="tags"><span class="tag tag-devops">Docker</span><span class="tag">Images</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/compose-checker/">Docker Compose Checker</a></h3>
      <p>Validate Docker Compose files for version compatibility and best practices.</p>
      <div class="tags"><span class="tag tag-devops">Docker</span><span class="tag">Compose</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/compose-to-k8s/">Docker Compose to K8s Converter</a></h3>
      <p>Convert docker-compose.yml to Kubernetes Deployments, Services, ConfigMaps and PVCs.</p>
      <div class="tags"><span class="tag tag-k8s">Kubernetes</span><span class="tag">Docker</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/github-actions-workflow-optimizer/">GitHub Actions Optimizer</a></h3>
      <p>Audit your workflow files for caching, pinning, security, and performance improvements.</p>
      <div class="tags"><span class="tag tag-devops">CI/CD</span><span class="tag">GitHub</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/ci-cost-calculator/">CI/CD Cost Calculator</a></h3>
      <p>Compare real costs across GitHub Actions, GitLab CI, CircleCI, Buildkite, and Jenkins.</p>
      <div class="tags"><span class="tag tag-devops">CI/CD</span><span class="tag">Cost</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/ci-calculator/">CI Pipeline Upgrade Calculator</a></h3>
      <p>Calculate the cost and effort of upgrading your CI/CD pipeline between platforms.</p>
      <div class="tags"><span class="tag tag-devops">CI/CD</span><span class="tag">Planning</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/api-deprecation-timeline/">API Deprecation Timeline</a></h3>
      <p>Track upcoming API sunsets across Google, AWS, Azure, Stripe, Twilio, and more.</p>
      <div class="tags"><span class="tag tag-devops">APIs</span><span class="tag">Deprecation</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/nginx-config-generator/">Nginx Config Generator</a></h3>
      <p>Generate production-ready Nginx configs with SSL, security headers, and reverse proxy settings.</p>
      <div class="tags"><span class="tag tag-devops">Web Servers</span><span class="tag">Nginx</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/config-drift/">Configuration Drift Detector</a></h3>
      <p>Detect configuration differences between environments. Catch drift before it causes incidents.</p>
      <div class="tags"><span class="tag tag-devops">Config</span><span class="tag">Monitoring</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/db-migration-risk/">Database Migration Risk Assessor</a></h3>
      <p>Assess risk, estimate downtime, and find breaking changes before database migrations.</p>
      <div class="tags"><span class="tag tag-devops">Database</span><span class="tag">Migration</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/cron-builder/">Cron Expression Builder</a></h3>
      <p>Build, parse, and test cron expressions visually. Preview next 10 executions across platforms.</p>
      <div class="tags"><span class="tag tag-devops">Scheduling</span><span class="tag">Cron</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/promql-builder/">PromQL Query Builder</a></h3>
      <p>Build Prometheus queries visually with templates, syntax highlighting, and Grafana/PrometheusRule export.</p>
      <div class="tags"><span class="tag tag-devops">Monitoring</span><span class="tag">Prometheus</span></div>
    </div>
  </div>

  <!-- RELEASE TRACKING & PLANNING -->
  <h2 class="section-title">Release Tracking &amp; Planning</h2>
  <p class="section-sub">Stay on top of versions, EOL dates, and upgrade paths</p>
  <div class="tools-grid">
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/stack-health/">Stack Health Scorecard</a></h3>
      <p>Get a comprehensive health report for your entire tech stack. EOL status, CVE counts, and upgrade urgency.</p>
      <div class="tags"><span class="tag">Health</span><span class="tag">Stack</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/stack-supported-report-card/">Stack Support Report Card</a></h3>
      <p>Check if your tech stack is still actively supported. Get a pass/fail grade for each component.</p>
      <div class="tags"><span class="tag">Support</span><span class="tag">Stack</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/eol-timeline/">EOL Timeline Visualizer</a></h3>
      <p>Visual timeline of end-of-life dates for 300+ technologies. Plan upgrades before support runs out.</p>
      <div class="tags"><span class="tag">EOL</span><span class="tag">Timeline</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/upgrade-planner/">Upgrade Path Planner</a></h3>
      <p>Get step-by-step upgrade paths with breaking change warnings and migration guides.</p>
      <div class="tags"><span class="tag">Upgrades</span><span class="tag">Planning</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/release-notes-diff/">Release Notes Diff</a></h3>
      <p>Compare release notes between any two versions. See what changed, what broke, and what to update.</p>
      <div class="tags"><span class="tag">Releases</span><span class="tag">Diff</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/migration-estimator/">Migration Effort Estimator</a></h3>
      <p>Estimate the effort and risk of migrating between technology versions or alternatives.</p>
      <div class="tags"><span class="tag">Migration</span><span class="tag">Planning</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/version-picker/">Which Version Should I Use?</a></h3>
      <p>Not sure which version to adopt? Get recommendations based on stability, support, and community adoption.</p>
      <div class="tags"><span class="tag">Versions</span><span class="tag">Advice</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/cloud-matrix/">Cloud Version Matrix</a></h3>
      <p>Compare runtime versions across AWS, GCP, and Azure. See what each cloud supports today.</p>
      <div class="tags"><span class="tag">Cloud</span><span class="tag">Matrix</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/badge-generator/">README Badge Generator</a></h3>
      <p>Generate SVG badges for your README showing version, EOL status, health grades, and CVE counts.</p>
      <div class="tags"><span class="tag">Badges</span><span class="tag">README</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/rss-builder/">Release Feed Builder</a></h3>
      <p>Build custom RSS feeds for the technologies you care about. Get notified when new versions drop.</p>
      <div class="tags"><span class="tag">RSS</span><span class="tag">Feeds</span></div>
    </div>
  </div>

  <!-- LANGUAGE & PACKAGE TOOLS -->
  <h2 class="section-title">Language &amp; Package Tools</h2>
  <p class="section-sub">Audit and optimize your projects by ecosystem</p>
  <div class="tools-grid">
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/package-audit/">package.json Deep Audit</a></h3>
      <p>Audit npm dependencies for license conflicts, bundle bloat, deprecated packages, and security risks.</p>
      <div class="tags"><span class="tag">npm</span><span class="tag tag-security">Security</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/go-module-checker/">Go Module Health Check</a></h3>
      <p>Analyze go.mod for outdated, deprecated, or vulnerable modules. Get a health grade for your Go project.</p>
      <div class="tags"><span class="tag">Go</span><span class="tag">Modules</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/dep-eol-scanner/">Dependency EOL Scanner</a></h3>
      <p>Scan your dependency files for end-of-life runtimes and frameworks that no longer receive security patches.</p>
      <div class="tags"><span class="tag">Dependencies</span><span class="tag">EOL</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/semver-checker/">SemVer Compatibility Checker</a></h3>
      <p>Check if version ranges are compatible. Validate semver constraints and find potential conflicts.</p>
      <div class="tags"><span class="tag">SemVer</span><span class="tag">Versions</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/pg-extensions/">PostgreSQL Extension Matrix</a></h3>
      <p>Check PostgreSQL extension compatibility across versions. Find which extensions work with your PG release.</p>
      <div class="tags"><span class="tag">PostgreSQL</span><span class="tag">Extensions</span></div>
    </div>
  </div>

  <!-- UTILITY TOOLS -->
  <h2 class="section-title">Utility Tools</h2>
  <p class="section-sub">Everyday developer utilities</p>
  <div class="tools-grid">
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/yaml-json-converter/">YAML ↔ JSON Converter</a></h3>
      <p>Convert, validate, and format YAML and JSON with real-time preview and presets for K8s, Docker, and more.</p>
      <div class="tags"><span class="tag tag-util">Utility</span><span class="tag">YAML</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/regex-tester/">Regex Tester &amp; Debugger</a></h3>
      <p>Test regex patterns with live highlighting, substitution mode, code generation, and cheat sheet.</p>
      <div class="tags"><span class="tag tag-util">Utility</span><span class="tag">Regex</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/cidr-calculator/">CIDR / Subnet Calculator</a></h3>
      <p>Calculate subnets, split networks, and visualize IP address allocation for IPv4 and IPv6.</p>
      <div class="tags"><span class="tag tag-util">Utility</span><span class="tag">Networking</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/dns-auditor/">DNS Record Auditor</a></h3>
      <p>Audit DNS records for any domain. Check A, AAAA, CNAME, MX, TXT, NS, and more.</p>
      <div class="tags"><span class="tag tag-util">Utility</span><span class="tag">DNS</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/tech-detector/">Technology Detector</a></h3>
      <p>Detect technologies used by any website. Frameworks, CMS, CDN, analytics, and server software.</p>
      <div class="tags"><span class="tag tag-util">Utility</span><span class="tag">Detection</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/repo-health/">Repository Health Report</a></h3>
      <p>Analyze any GitHub repository for maintenance health. Activity, issues, PRs, and community signals.</p>
      <div class="tags"><span class="tag tag-util">Utility</span><span class="tag">GitHub</span></div>
    </div>
    <div class="tool-card">
      <h3><a href="https://releaserun.com/tools/git-conflict-helper/">Git Conflict Helper</a></h3>
      <p>Parse and resolve git merge conflicts visually. Side-by-side diff, batch operations, and one-click resolution.</p>
      <div class="tags"><span class="tag tag-util">Utility</span><span class="tag">Git</span></div>
    </div>
  </div>

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