COMPOSE

COmpositional Meaning Practice · Online Semantics Engine — version 1.3.0

COMPOSE is a browser-based companion for learning compositional formal semantics in the Heim & Kratzer / Coppock & Champollion tradition. Students compose a sentence's meaning bottom-up over a syntactic tree, choosing composition rules at each node; denotations are genuine typed λ-terms, so answers are graded by meaning (α/β/η-equivalence), not surface form.

How to cite

If COMPOSE plays a role in your teaching or research, please cite it:

Stephen, Thomas (2026). COMPOSE: Compositional Meaning Practice — an online semantics engine (version 1.3.0). https://compose.tstephen.com
@misc{stephen2026compose, author = {Stephen, Thomas}, title = {{COMPOSE}: Compositional Meaning Practice --- an online semantics engine}, year = {2026}, note = {Version 1.3.0}, url = {https://compose.tstephen.com} }

The library

Everything lives in one app at compose.tstephen.com. The starter page opens with a sample worksheet; the built-in library loads on demand through fixed six-character unlock codes — enter one in the app ("⊕ Unlock with a code"), or open its /?code=… link or QR, and the collection joins your sidebar. No account needed:

Older links (/cc, /hk, /papers, the chapter pages, /editor) still work: they forward into the app, unlocking the right content as they land.

Accounts

Everything above works without an account — including the library's own unlock codes: every built-in worksheet, chapter and collection has a fixed six-character code (shown on its page in the app) that adds it to the sidebar of whoever enters it, account or not. An optional account (created from the app's sign-in page) stores: your email address, a password hash, your exercise progress, and — for class codes you redeem — which versions you are enrolled in. Instructor accounts additionally own the versions they host. The server sends no email of any kind: there is no address verification and no self-service password reset (a forgotten password is reset by the administrator).

Credits and lineage

The bundled worksheet library tracks Elizabeth Coppock & Lucas Champollion's Invitation to Formal Semantics (§6–§13) and Irene Heim & Angelika Kratzer's Semantics in Generative Grammar, plus a classic-papers shelf: Partee (1986), Partee & Rooth (1983), Montague's PTQ (1973), Davidson (1967), Krifka (1998), Barwise & Cooper (1981) and Link (1983). Textbook companions are original paraphrase — nothing is reproduced from the textbooks. Paper companions quote sparingly and with attribution: their notes contain only short attributed quotes (from the papers or published presentations of them), the papers' own numbered definitions, and explicitly flagged notes on how this implementation renders them.

COMPOSE is written in homage to the Lambda Calculator (Champollion, Tauberer & Romero), the classic teaching tool of this tradition.

Source

COMPOSE is open source: github.com/Vrier/compose (MIT). It runs on PocketBase behind Caddy.

© 2026 Thomas Stephen · Open the app · Instructor dashboard