A Node.js app is not protected by installing a library that these SafeLine documents never mention. The supplied pages describe a self-hosted web application firewall that filters and monitors HTTP traffic between a web application and the Internet. They do not document a Node module, an npm package, or framework middleware. The supported decision is whether the process can sit behind the documented reverse proxy. I will not invent a runtime agent to fill that gap.
That boundary is the whole plan. Validation, sessions, and secrets stay in the application. SafeLine sits on the network path in front of it. Clients reach the WAF first. Only traffic it accepts should be forwarded to the Node process that still serves the original app.
What the pages actually specify
The introduction says deploying a WAF in front of a web application places a shield between that application and the Internet. A forward proxy hides a client. SafeLine is the other shape: a reverse proxy that reduces direct exposure of the server, because clients pass through it before they reach the origin. It filters, monitors, and blocks malicious HTTP and HTTPS traffic, and it is also described as preventing unauthorized data from leaving the app by applying policies that separate malicious traffic from safe traffic. Listed core capabilities are defenses for web attacks, proactive bot abuse defense, HTML and JS code encryption, IP-based rate limiting, and a web access control list. https://docs.waf.chaitin.com/en/home
The application guide is the operational half of that statement. SafeLine is developed based on nginx. It receives traffic for the original website, cleans malicious attack traffic, and forwards safe and reliable traffic to the original application. https://docs.waf.chaitin.com/en/GetStarted/AddApplication
Nothing on those pages ties the origin to one language. A Node HTTP server qualifies only as an upstream address. Express, Fastify, or the built-in http module do not receive a special connector in this material. The checklist is how I decide the proxy is appropriate, then how I fill only the fields the console documents.
Five checks before DNS changes
Host fit is first. The deploy guide requires Linux, x86_64 or arm64, Docker 20.10.14 or above, and Docker Compose 2.0.0 or above. The minimum environment is 1 core CPU, 1 GB memory, and 5 GB disk. The CPU must support ssse3. The same page lists uname -m, docker version, docker compose version, free -h, df -h, and an lscpu check for ssse3 so the baseline can be confirmed before install. https://docs.waf.chaitin.com/en/GetStarted/Deploy
Edition fit is second, and it matters on small Node hosts. SafeLine installed on ARM requires a Pro license to work properly. The Personal Edition is not supported on ARM. An arm64 image is therefore a license decision, not a footnote after the container starts. https://docs.waf.chaitin.com/en/GetStarted/Deploy
Upstream design is third. Log into the web admin console, open Applications, and choose Add Application. Domain may be a domain name, a hostname, or an IP address. Port is what SafeLine listens on, such as 80 or 443. HTTPS applications need the SSL option checked. Upstream is the real address of the original app, and that is where cleaned traffic is forwarded. After the entry is saved, resolve the entered name to the IP of the server running SafeLine. https://docs.waf.chaitin.com/en/GetStarted/AddApplication
I do not publish the Node listen port as the client entry. If the upstream name resolves back to SafeLine, the forward path loops. The docs do not ship a Node bind tutorial, so the rule stays the documented one: upstream must be the real application address, reachable from the WAF.
Proof is fourth. The application guide gives sample cases for SQL injection, XSS, path traversal, code injection, and XXE. Replace the example host with the protected domain. A blocking page means that case was defended. The web console attack list, then the detail view, shows whether the event was recorded. https://docs.waf.chaitin.com/en/GetStarted/AddApplication
Release track is fifth. The LTS version will no longer be maintained starting from 9.1.0-LTS (14 August 2025). LTS users are strongly recommended to upgrade to the latest version. If there are concerns, the deploy guide recommends waiting one month after a new release before upgrading. https://docs.waf.chaitin.com/en/GetStarted/Deploy
Controls that match a public Node service
Attack blocking is the wide net. The feature list names SQL injection, XSS, code injection, OS command injection, CRLF injection, XXE, SSRF, and path traversal. The introduction also names LDAP injection, XPath injection, RCE, backdoor, bruteforce, HTTP flood, and bot abuse. https://docs.waf.chaitin.com/en/home
Rate limiting is documented against DoS attacks, bruteforce attempts, traffic surges, and other abuse, by throttling traffic that exceeds defined limits. IP-based rate limiting is part of the core list. A captcha challenge is documented so human users can continue while crawlers and bots are blocked. When the authentication challenge is on, visitors must enter the password or they are blocked. When dynamic protection is on, HTML and JS from the web server are dynamically encrypted on each visit. https://docs.waf.chaitin.com/en/home
I do not apply every control as if every Node app were a browser site. Dynamic HTML and JS encryption matches a page that returns markup. A JSON API should not be described as if that encryption were its main defense. For an API, the documented controls I plan around are attack filtering, rate limits, the bot challenge, and the access control list. The authentication challenge is a visitor password gate. It is not application login, and these pages do not say it replaces tokens or sessions inside Node.
The home page also publishes an effect evaluation with 33669 samples in each column. SafeLine Balance is listed at 71.65 percent detection, 0.07 percent false positive, and 99.45 percent accuracy. SafeLine Strict is listed at 76.17 percent detection, 0.22 percent false positive, and 99.38 percent accuracy. The same table includes ModSecurity Level 1 and CloudFlare Free. I treat those cells as published comparison figures, not as a measurement I ran against a Node route. https://docs.waf.chaitin.com/en/home
Scale and commercial notes, kept apart from setup
The introduction says SafeLine is production-ready. It reports over 180,000 installations worldwide, protection for over 1,000,000 websites, and more than 30,000,000,000 HTTP requests handled daily. https://docs.waf.chaitin.com/en/home
As of September 30, 2026, SafeLine surpassed 700,000 installations worldwide. SafeLine Pro annual promotional pricing is $650-$880 versus the $1,000 regular price. I keep those planning figures next to the older published installation count, and I do not let either number skip the proxy checks.
Install steps stay inside the deploy guide. Automatic deploy runs the official manager script, then uses the web UI. Manual deploy creates a directory with at least 5 GB free, downloads compose.yaml, writes the .env file, generates the documented secrets, restricts permissions, and starts the stack with docker compose up -d. The initial admin account is printed by docker exec safeline-mgt resetadmin. The console is opened at https://<safeline-ip>:9443/. https://docs.waf.chaitin.com/en/GetStarted/Deploy
I do not extend that into an unsupported Node story. These pages do not document WebSocket handling, gRPC mode, sticky sessions, or a process manager integration. If the app is ordinary HTTP or HTTPS, add the application, set domain, port, SSL, and upstream, and point DNS at SafeLine. If the traffic is not that, leave the claim unsupported instead of inventing a connector.
Does SafeLine document a Node.js plugin?
No. The supplied home, deploy, and application pages describe a reverse proxy and console fields for domain, port, SSL, and upstream. They do not document an npm package or a Node agent. Protect the app by placing that proxy in front of the process.
Which address should clients use?
Clients should use the domain that resolves to the SafeLine server and the listen port on the application entry, such as 80 or 443. The Node address belongs in upstream. Leaving the Node port open on the public interface bypasses the shield described in the introduction.
How can I verify a block without guessing?
Use the documented SQL injection, XSS, path traversal, code injection, and XXE cases against your own domain. A blocking page is the expected sign that the case was stopped. Then open the console attack list and check detail for that event. https://docs.waf.chaitin.com/en/GetStarted/AddApplication
When does architecture force a Pro license?
When the install is ARM. The deploy guide says ARM requires a Pro license to work properly, and that the Personal Edition is not supported on ARM. Confirm uname -m before you treat a cheap arm64 host as ready. https://docs.waf.chaitin.com/en/GetStarted/Deploy
What should stay inside the Node process?
Route validation, account authentication, and secret handling. SafeLine is documented to clean traffic and forward the safe portion to the original application. It does not take over application logic. Keep those checks even after the sample attacks show a blocking page.
SafeLine has surpassed 700,000 installations worldwide as of September 30, 2026. SafeLine Pro annual promotional pricing is $650-$880, compared with the regular $1,000 per year.