Rlg

rlg — RustLogs

Near-lock-free structured logging for Rust, plus an ecosystem of companion crates: CLI tooling, MCP server, OTLP exporter, tower middleware, WebAssembly bindings, PII redaction, test utilities, and aggregation reports.

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This is the Cargo workspace root. The library lives at [crates/rlg](crates/rlg). Ten companion crates ship from this workspace, all at lockstep version 0.0.11.

The rlg ecosystem

| Crate | What it does | Use case | |---|---|---| | [rlg](crates/rlg/README.md) | Near-lock-free structured logging engine. 65k-slot ring buffer, deferred formatting, 14 output formats, native OS sinks (os_log via syslog(3), journald). | Embed structured logging in any Rust binary or library. | | [rlg-cli](crates/rlg-cli/README.md) | rlg binary — jq for structured logs. Tail, filter, convert across all 14 formats. | Pipe my-service \| rlg --min-level error --format ecs from the shell. | | [rlg-mcp](crates/rlg-mcp/README.md) | Model Context Protocol server exposing rlg streams as tools to LLM agents. | Claude Desktop, Cursor, mcp.run agents reading your logs. | | [rlg-otlp](crates/rlg-otlp/README.md) | OpenTelemetry network exporter (OTLP/HTTP JSON). | Ship records to Honeycomb, Datadog, Tempo, Jaeger, otelcol. | | [rlg-tower](crates/rlg-tower/README.md) | tower::Layer emitting per-request structured access logs. | axum, tonic, hyper, lambda_runtime — any tower::Service. | | [rlg-wasm](crates/rlg-wasm/README.md) | wasm-bindgen wrapper for browser / Deno / Cloudflare Workers / Bun, plus a WASI 0.2 component interface for wasmtime hosts. | Structured logging from JS or WASI 0.2 components. | | [rlg-redact](crates/rlg-redact/README.md) | PII / secret redaction between Log::fire() and the sink. Aho-Corasick fused alternation regex. | Compliance, GDPR, audit-trail safety. Built-in patterns for cards, JWTs, bearers, emails, IPs, AWS keys. | | [rlg-test](crates/rlg-test/README.md) | Test utilities — capture rlg records in a #[test] scope and assert on them with assert_logged!. | Downstream library tests verifying their structured log output. | | [rlg-report](crates/rlg-report/README.md) | Log digest / analytics: count by level, top components, top errors, latency percentiles. CLI + library mode. | Operational dashboards, daily error reports, oncall triage. | | [rlg-ebpf](crates/rlg-ebpf/README.md) | Enricher trait + ProcessEnricher (portable) + EbpfEnricher scaffold (Linux, behind the ebpf feature) for automatic PID / process-name attributes. | Automatic host-level context on every record without app code changes. | | xtask (internal, unpublished) | cargo xtask check-all / coverage / audit / doc / examples / bench / release. | Maintainer automation. |

Install one, install all

[dependencies]
rlg         = "0.0.11"
rlg-otlp    = "0.0.11"  # ship to an OTLP collector
rlg-tower   = "0.0.11"  # HTTP middleware
rlg-redact  = "0.0.11"  # PII redaction

[dev-dependencies]
rlg-test    = "0.0.11"  # assertions in your tests

CLI binaries:

cargo install rlg-cli       # the `rlg` binary
cargo install rlg-mcp       # the `rlg-mcp` MCP server
cargo install rlg-report    # the `rlg-report` digest tool

Workspace layout

.
├── Cargo.toml            # workspace manifest (profiles, members)
├── README.md             # ← you are here
├── CHANGELOG.md / CONTRIBUTING.md / SECURITY.md
├── LICENSE-{APACHE,MIT}
├── crates/
│   ├── rlg/              # core library
│   ├── rlg-cli/          # `rlg` binary + filter/render lib
│   ├── rlg-mcp/          # MCP server
│   ├── rlg-otlp/         # OTLP/HTTP exporter
│   ├── rlg-tower/        # tower::Layer
│   ├── rlg-wasm/         # wasm-bindgen + WASI 0.2 component
│   ├── rlg-redact/       # PII / secret scrubber (Aho-Corasick)
│   ├── rlg-test/         # test utilities
│   ├── rlg-report/       # log digest binary + lib
│   ├── rlg-ebpf/         # Enricher trait + eBPF (Linux) scaffold
│   └── xtask/            # internal automation (publish = false)
└── .github/
    └── workflows/
        ├── ci.yml        # delegates to sebastienrousseau/pipelines
        └── release.yml   # workspace-aware crates.io publisher

Quick links

• Core docs: [crates/rlg/README.md](crates/rlg/README.md) · docs.rs/rlg
• Contributing & signing policy: [CONTRIBUTING.md](CONTRIBUTING.md)
• Security policy: [SECURITY.md](SECURITY.md)
• Release notes: [CHANGELOG.md](CHANGELOG.md)

License

Dual-licensed under Apache 2.0 or MIT, at your option.

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: sebastienrousseau
• Source: sebastienrousseau/rlg
• License: Apache-2.0
• Homepage: http://doc.rustlogs.com/

Install and usage instructions live in the source repository linked above.