Sinatra Performance Monitoring
Errors, logs, and traces for your Sinatra and Rack applications. Scout's Ruby agent automatically instruments Sinatra routes, ActiveRecord queries, and background jobs with minimal overhead. No Rails required. Supports Ruby 2.1+ and any Rack-based framework.
Errors, Logs, and Traces
Errors, Logs, and Traces in One View for Sinatra Apps
Scout connects Sinatra route errors to the full transaction trace and surrounding log lines in a single view. When a route handler raises an exception, you see the error, the request trace with per-operation timing, and the log output together. No switching between your error tracker, log tool, and APM.
Error Monitoring
Automatic exception capture across Sinatra routes and Rack middleware. Errors are grouped, linked to the originating trace, and enriched with request context so you see which endpoints are affected.
Log Management
Log output is enriched with trace context and forwarded alongside performance data. Filter logs by trace ID to see exactly what your Sinatra application was doing before, during, and after an issue.
App Traces
Transaction tracing with code-level visibility into Sinatra route handlers, ActiveRecord queries, and external HTTP calls. Detailed backtraces show the exact line of code responsible for slow requests.
Query Analysis
N+1 Detection in Sinatra and ActiveRecord
Scout automatically detects N+1 query patterns in ActiveRecord within Sinatra routes and background jobs. The agent identifies repeated query patterns and shows the code location and performance impact of each N+1. Works without any configuration regardless of whether you use Sinatra classic or modular style.
Auto-Instrumentation
What Scout Instruments in Your Sinatra App
Scout's Ruby agent auto-instruments Sinatra routes at the framework level. ActiveRecord, Redis, ElasticSearch, Mongoid, Moped, and HTTP clients including Net::HTTP, HTTPClient, and Typhoeus are captured automatically. Background job frameworks including Sidekiq, Resque, GoodJob, Solid Queue, DelayedJob, Shoryuken, and Sneakers appear with per-job timing. No manual instrumentation required.
Supported Frameworks
Works with the Sinatra frameworks you already use
Scout auto-instruments the frameworks and libraries in your stack. No manual configuration required.
Web Frameworks
- Sinatra
- Rack
- Grape
Databases
- ActiveRecord
- Redis
- ElasticSearch
- Mongoid
Background Jobs
- Sidekiq
- Resque
- GoodJob
- DelayedJob
HTTP Clients
- Net::HTTP
- HTTPClient
- Typhoeus
Memory Profiling
Memory Bloat Detection for Sinatra Apps
Sinatra applications and their background workers can accumulate memory over time. Scout detects memory bloat at the transaction level, showing which route handlers and code paths are responsible for memory growth. Requires Ruby 2.1+.
AI Native
Query Your Sinatra App Data from AI Assistants and the Terminal
Scout offers hosted and local MCP servers with 17 tools, a Go CLI available via Homebrew with TOON format for LLM output, and a public API. Query your Sinatra application's errors, traces, and N+1 insights from Claude Code, Cursor, or the terminal.
MCP Server
Hosted or local MCP server with 17 tools covering apps, endpoints, traces, errors, insights, background jobs, and usage data. Works with Claude Code, Cursor, VS Code Copilot, and any MCP-enabled assistant.
Scout CLI
Go binary available via Homebrew. Query app metrics, endpoint performance, traces, error groups, and insights from the terminal. Outputs human-friendly tables or TOON format for LLM consumption.
Public API
Full programmatic access to your monitoring data for building custom integrations, dashboards, or automation workflows.
Get Started in Minutes
Add Scout to Your Sinatra App
Get Scout running on your Sinatra app in under 3 minutes.
Add to your Gemfile:
gem 'scout_apm'Run:
bundle installDownload your customized config file, placing it at config/scout_apm.yml.
Deploy.
FAQ
Sinatra Monitoring FAQ
What is the best monitoring tool for Sinatra?
Scout Monitoring provides integrated errors, logs, and traces for Sinatra and Rack applications. The Ruby agent instruments Sinatra routes automatically, detects N+1 queries in ActiveRecord, tracks memory bloat at the transaction level, and connects exceptions to the full request trace. Setup takes under 3 minutes with no framework changes required.
How do I add APM to a Sinatra app?
Add the scout_apm gem to your Gemfile, run bundle install, add a config file at config/scout_apm.yml, and deploy. Scout instruments Sinatra at the Rack middleware level so it works with classic and modular Sinatra apps, and with any other Rack-based framework running alongside.
Does Scout work with Rack apps?
Yes. Scout's Ruby agent instruments at the Rack level, so it works with any Rack-based framework including Sinatra, Grape, and custom Rack apps. Route-level timing, error capture, and N+1 detection all apply regardless of the framework sitting above Rack.
How is monitoring a Sinatra app different from monitoring Rails?
The core monitoring is the same: request tracing, N+1 detection, memory bloat, error capture, and log context. The difference is that Sinatra does not have ActionController or ActionView, so those layers are not present in traces. You see timing broken down into route handler, ActiveRecord queries, HTTP calls, and application code instead.
Does Scout detect N+1 queries in Sinatra?
Yes. Scout automatically detects N+1 query patterns in ActiveRecord within Sinatra route handlers and background jobs. The agent identifies repeated query patterns, shows the exact code location, and reports the performance impact. No configuration or annotation required.
Does Scout support error monitoring for Sinatra?
Yes. Scout captures exceptions across Sinatra routes and Rack middleware automatically. Each error is linked to the request trace that caused it and shown alongside the surrounding log context. You see the error, the trace, and the logs in one view.
Can I use Scout with Sidekiq in a Sinatra app?
Yes. Scout instruments both Sinatra routes and Sidekiq workers in the same agent. Background jobs appear as their own transactions with per-job timing, queue metrics, and error tracking. N+1 detection and memory bloat analysis apply to Sidekiq jobs the same way they apply to Sinatra requests.