sslx offers a modern, rust-based alternative to openssl cli for certificate management

On October 15, 2026, developer glincker released sslx, a command-line interface tool designed to streamline how engineers interact with TLS certificates. Built with Rust and the rustls library, this utility consolidates multiple common cryptographic tasks into a single binary, offering a faster and more intuitive experience than traditional OpenSSL workflows.

What happened

The release introduces sslx as a direct competitor to the ubiquitous but notoriously complex OpenSSL command-line tools. The primary goal is to eliminate the need for engineers to constantly search for correct flag combinations when inspecting certificates, verifying chains, or generating keys. By leveraging Rust, the tool avoids dependencies on system-level OpenSSL installations, ensuring consistent behavior across different environments.

The tool provides a suite of functions that typically require separate commands or external web services. For instance, it can grade a host’s TLS configuration similarly to SSL Labs, check certificate expiration dates for multiple domains simultaneously, and decode various file formats including JWTs. It also supports generating self-signed certificates and certificate signing requests with simplified syntax, making it particularly useful for local development and quick diagnostics.

Installation options are flexible, catering to different workflow preferences. Users can install via Cargo, the Rust package manager, or use Homebrew on macOS. Prebuilt binaries are available for Linux and macOS Apple Silicon architectures, allowing for immediate deployment without compilation. The project is hosted on GitHub under an MIT license, encouraging community contributions and integration into existing DevOps pipelines.

Key details

• Single binary architecture: Combines certificate inspection, TLS connection testing, and key generation into one executable without requiring system OpenSSL.
• TLS grading: Assigns letter grades from A+ to F based on protocol version, cipher strength, and chain completeness, similar to online SSL testing tools.
• Batch expiry checks: Allows users to check certificate expiration for multiple hosts at once, returning exit code 1 if any certificate expires within seven days.
• Format conversion and decoding: Automatically detects and converts between PEM, DER, and PKCS12 formats, and can decode JWT tokens directly in the terminal.
• JSON output support: Every command includes a --json flag, enabling easy parsing for scripting, CI/CD pipelines, and automated monitoring systems.
• Performance improvements: Benchmarks on macOS M2 show significantly faster startup and execution times compared to OpenSSL, with certificate inspection taking 2.1ms versus 9.4ms.

Background

OpenSSL has long been the standard library for implementing Transport Layer Security protocols, but its command-line interface is often criticized for being unintuitive and verbose. Engineers frequently struggle with remembering specific flags for basic tasks like viewing certificate details or verifying chain trust. This complexity can lead to errors in production environments, such as misconfigured servers or expired certificates causing outages.

Rust has emerged as a popular language for building system-level tools due to its memory safety guarantees and performance. By using rustls, a modern TLS implementation written in Rust, sslx avoids the legacy baggage associated with OpenSSL. This shift allows for a cleaner codebase and potentially fewer security vulnerabilities related to memory management, which is a significant concern in cryptographic software.

Why it matters

For teams managing self-hosted infrastructure, certificate management is a critical but often tedious task. Expired certificates can take down services unexpectedly, leading to downtime and loss of user trust. Tools that simplify the verification and monitoring process help prevent these incidents by making it easier for engineers to regularly check the health of their TLS configurations. The ability to grade TLS setups from the terminal allows for quick audits without relying on external web services, which may not be accessible in air-gapped or private network environments.

The integration of JSON output and specific exit codes makes sslx highly suitable for automation. DevOps engineers can incorporate certificate checks into continuous integration pipelines, ensuring that new deployments meet security standards before going live. The fast execution time means these checks can be run frequently without adding significant overhead to build processes. This level of automation reduces the manual burden on sysadmins and helps maintain consistent security postures across multiple services.

Furthermore, the simplification of certificate generation for local development accelerates the workflow for developers. Creating self-signed certificates with proper Subject Alternative Names (SANs) is often a hurdle in setting up local testing environments. By providing a straightforward command for this task, sslx reduces friction in the development lifecycle, allowing teams to focus more on application logic rather than infrastructure setup.

What you can do

• Install sslx using Cargo, Homebrew, or by downloading prebuilt binaries from the GitHub releases page to test its capabilities in your environment.
• Replace complex OpenSSL commands with sslx equivalents for routine tasks like inspecting certificates or verifying chains to improve script readability.
• Integrate the expiry command into your cron jobs or CI pipelines to receive early warnings about upcoming certificate expirations.
• Use the grade feature to perform regular TLS audits of your public-facing services directly from your terminal without external dependencies.
• Leverage the JSON output option to parse certificate data programmatically for custom dashboards or monitoring alerts.
• Generate self-signed certificates for local development using the generate command to quickly set up secure testing environments.