Composer

Composer is a trading platform and brokerage that lets retail investors create, test and automatically execute rules-based investment strategies, marketed under the name "symphonies." Users can describe goals, strategy and risk constraints in natural language and an AI-assisted editor generates a corresponding strategy, or they can build and modify strategies directly in a no-code visual editor using conditional logic, weighting schemes (custom weight, inverse volatility, market capitalization or equal weighting) and dynamic sorting, filtering and selection from a pool of candidate assets. Strategies are backtested against benchmarks or other strategies, with modelled fees, slippage and final value, and a historical allocation graph showing how holdings shifted over time.

Composer acts as the brokerage itself, handling order execution and periodic automatic rebalancing end-to-end; accounts are created and funded in the app, and supported account types include taxable brokerage accounts as well as Traditional and Roth IRAs, with transfer fees covered within stated limits. The platform also offers a library of pre-built strategies organized by categories such as Long Term, Technology Focus and Diversification, and a Community section where users publish, remix, invest in or modify strategies built by others. The company operates through two entities: Composer Technologies, Inc. and the broker-dealer affiliate Composer Securities LLC.

Founding story

Founded in 2020, the company was built around the goal of making quantitative investing tools accessible to non-programmers. Its listed founders are Ben Rollert (Founder) with co-founders Ananda Aisola and Ronny Li.

Business model

Composer operates as the brokerage for its users' automated strategies and charges no trade commissions and no management fees. Revenue is tied to a subscription: a flat fixed monthly fee marketed as the "Composer Trading Pass," which unlocks unlimited automated trading across all of a user's accounts and permits opening multiple accounts at no additional cost. A free trial is offered, and other fees may apply per the published fee schedule.

Simple fixed monthly subscription (Composer Trading Pass) rather than trading commissions or management fees; additional fees may apply under the company's fee schedule.

Traction

The company reports more than $37 billion in cumulative trading volume, more than 18 million orders executed and more than 2 million account rebalances.

Latest developments

Composer announced that it has joined SoFi, with the homepage carrying the announcement and linking to a blog post, and the platform now branded "Composer by SoFi."