Compose vs Confidence by Spotify

Compose is a pay-as-you-go web platform for A/B testing and conversion rate optimization. It supports A/B/n, split URL, split theme, and split template tests, with custom goals, audiences, triggers, and traffic allocation. A visual editor and audience targeting are available for building and directing experiments. For planning, teams can use a shared hypothesis backlog, PIE prioritization, and an experimentation roadmap. Reports update in real time and include frequentist statistical calculations; GA4 and BigQuery integrations are listed. Shopify users can create no-code experiments on themes and templates through Shopify’s editor. Compose says its client-side testing uses AWS Lambda@Edge for speed and to avoid flicker. The product lists unlimited experiments, variations, collaborators, and projects. You can explore it without charge until launching a first experiment, but there is no traditional free trial. The Early Adopter Plan is $0.00 per month, billed at $0.0012 per monthly tested user, with usage billed monthly for the prior month. Server-side testing is not available.

Confidence by Spotify is a warehouse-native platform for experimentation and feature management. Teams can run A/B tests, define metrics in their warehouse, manage feature flags, and use product data to guide decisions. Experimentation tools include sequential testing, automatic guardrails, and CUPED variance reduction. Rollouts can ramp releases from 1% to 100% while guardrails monitor for regressions, with one-click reverting. Feature flags include typed schemas, warehouse-powered targeting, and cleanup support; the Free plan includes unlimited flags and seats. Analytics accepts plain-English questions and returns charts and causes grounded in experiments, metrics, and warehouse data. Every account receives a managed warehouse, while paid plans can connect BigQuery, Snowflake, Redshift, and Databricks, with analysis in inspectable SQL. Session Replay overlays real user sessions with flags and experiment variants. The service is built on the OpenFeature API and offers migration kits to rewrite competitor SDK code to that standard. Pricing includes a Free plan with 75,000 credits per month and Growth at $449 a month. A 30-day trial is listed.