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Change log levels in real-time.

You're one line of code away from real-time control over every logger. Every service. Every environment. Temporarily turn on debug in production to diagnose an issue. Instantly silence noisy loggers. Reduce spend.

Try the live demo → Read the docs
Smpl Logging tree view showing discovered loggers with real-time level controls

01

Auto-discovery

Drop in the SDK and every logger your application uses gets reported up automatically. Pick the ones you want to control. The rest stay out of your way.

02

One-line install

SmplClient().logging.install() — that's it. The SDK attaches to your existing logger framework, reports discovered loggers, and listens for level changes.

03

Live updates

Change a level in the console. SDKs receive the change via WebSocket and apply it immediately. No deploys, no rolling restarts, no per-server SSH.

Compatibility

Drops into your existing logging stack.

Six language SDKs, each with built-in adapters for that ecosystem's most popular logging frameworks — out of the box, no glue code.

C#
  • Microsoft.Extensions.Logging
  • Serilog
Go
  • log/slog (stdlib)
  • Uber Zap
Java
  • java.util.logging
  • Log4j2
  • SLF4J + Logback
Python
  • logging (stdlib)
  • Loguru
Ruby
  • Semantic Logger
  • stdlib Logger
TypeScript
  • Pino
  • Winston

…and any other framework.

The built-ins cover the popular ones — but the adapter interface is just five methods: discover existing loggers, apply a level, hook new ones. Implement it for any framework, call registerAdapter(), and the SDK treats it identically to the built-ins. No source changes, no special builds, no waiting on us.

Build a custom adapter →

Need support for another language? Contact us — we can usually ship a new SDK within 48 hours.

How Smpl Logging stacks up

Real-time remote log-level control is a niche Prefab essentially owns — change a log level in the console and the change reaches every running process in milliseconds, with no redeploy. Smpl Logging delivers the same control on more frameworks, with a one-line install and no per-server / per-request metering.

Each ✓ indicates the feature is available from that vendor at some tier. Cells naming a specific tier indicate the feature is gated to that tier or higher. Prices show all of the vendor's published tiers.

— not documented publicly as of 2026-05-25.

Prefab Cloud 5 Smpl Logging
Real-time log level changes (no redeploy) ✓ ✓
Auto-discovery — loggers register themselves from code ✓ ✓
Per-environment level overrides ✓ ✓
Audit log / change history ✓1 ✓
Webhooks for change events UNCLEAR2 ✓
Version history / point-in-time rollback UNCLEAR ✓
CLI ✓ ✓
Role-based security UNCLEAR4 ✓
Google & Microsoft SSO ✓ ✓
Custom SAML / OIDC SSO ✓ ✓
Organize loggers by group ✓
Terraform provider ✓
One-line instrumentation3 ✓
Pluggable adapter API — implement any unsupported framework ✓
Managed loggers Unlimited Unlimited6
Environments Unlimited Unlimited6
Console users Unlimited Unlimited6
Read-only users Unlimited Unlimited
Servers $2/server7 Unlimited
Connections Unlimited Unlimited
API requests Metered Unlimited
— Frameworks —
Python logging (stdlib — Django, Flask, FastAPI) ✓ ✓
Java SLF4J + Logback ✓ ✓
Java Log4j2 ✓ ✓
Java JUL (java.util.logging) ✓ ✓
Ruby Semantic Logger ✓ ✓
Ruby stdlib Logger (Rails, Ougai) UNCLEAR ✓
Python Loguru ✓
TypeScript Winston ✓
TypeScript Pino ✓
Go log/slog (stdlib) ✓
Go Uber Zap ✓
.NET Microsoft.Extensions.Logging ✓
.NET Serilog ✓
Monthly price Free / $99 / $499 Free / $49 / $99 / $249
  1. ↩ Prefab Enterprise advertises 2-year audit-log retention; Pro audit-log retention is not explicitly published.
  2. ↩ Prefab confirms Slack notifications for changes; a generic HTTP webhook destination is not independently confirmed in public docs.
  3. ↩ Smpl Logging is one line — client.logging.install() auto-detects every supported logging framework present in the runtime. Prefab requires per-framework wiring (e.g. SemanticLogger.add_appender(filter: Prefab.log_filter) for Ruby, listener configuration for Java).
  4. ↩ Tag-based ABAC tied to SAML roles exists at Pro+; per-environment write gates specifically not documented.
  5. ↩ Prefab Cloud is rebranding to "Reforge Launch" following Reforge acquisition; pricing and feature set verified live on prefab.cloud as of May 2026.
  6. ↩ Smpl limits scale by plan; the figure shown is the Enterprise (top) tier — lower tiers have smaller limits. See pricing for the per-plan values.
  7. ↩ Prefab Cloud includes 5 connected servers free, then $2 per additional server.