📝 Add an alternatives section

Add a short README section under Alternatives, one heading per
alternative (ts-pattern, Effect.Match, match-iz and plain switch), each
saying what it is and what tiny-pattern-ts is or does differently. State
the data-last, pipe-friendly shape in Description.

- measure the footprint: ~0.2 kB minified + gzipped, not the
  unminified ~1.8 kB; ts-pattern is ~2 kB
- correct match-iz: it ships types, it just cannot prove exhaustiveness
- drop switchcase / ts-match (unmaintained)
- check off the backlog task

Resolves: backlog "Add comparison section vs. other TS pattern-matching libs"

README.md

@@ -38,7 +38,9 @@ assert.equal(phoneOutput, "PHONE: +1 555 0100");
 The main goal of `tiny-pattern-ts` is to make pattern matching type-safe with a
 lean syntax. This is accomplished by being exhaustive and passing typed
 parameters per branch to the handlers — supported by an outstanding
-autocomplete and a tiny footprint.
+autocomplete and a tiny footprint. The matchers are data last and pipe-friendly:
+build the handler map once, then apply the resulting matcher to values
+(`match(value)`, or `pipe(value, match)`).
 
 See [development/library.md](./development/library.md) for the design decisions
 and [Caveats](#caveats) for the limits.
@@ -284,6 +286,43 @@ provable exhaustiveness — to automate what a `switch` and a default arm alread
 cover. The type-level cost of supporting open universes is recorded in
 [development/library.md](./development/library.md#supported-universes).
 
+## Alternatives
+
+### [`ts-pattern`](https://github.com/gvergnaud/ts-pattern)
+
+- is the full structural matcher — nested and partial patterns, guards, unions,
+  captures — exhausting at `.exhaustive()`
+- has a fluent `.with(…)` chain that is heavy on syntax; tiny-pattern-ts is one
+  handler map
+- is about 2 kB minified and gzipped; tiny-pattern-ts is 0.2 kB
+- reach for it when you need a feature tiny-pattern-ts does not cover
+
+### [Effect's `Match`](https://effect.website/docs/code-style/pattern-matching/)
+
+- is the same piped matcher (`Match.type` / `Match.when` / `Match.exhaustive`),
+  but only as part of the `effect` ecosystem
+- tiny-pattern-ts is standalone: no runtime dependency to buy into
+
+### [`match-iz`](https://github.com/shuckster/match-iz)
+
+- expresses patterns in the TC39 proposal's style, deciding each case at runtime
+- is written in JavaScript with hand-maintained declarations, so its types do
+  not prove the cases exhaustive
+- tiny-pattern-ts does: exhaustiveness is a compile-time guarantee, not an
+  `otherwise` fallback
+
+### plain `switch` (baseline)
+
+- is the zero-dependency baseline — pair it with
+  [`eslint-plugin-strict-pattern-matching`](https://www.npmjs.com/package/eslint-plugin-strict-pattern-matching)
+  for exhaustiveness
+- is a statement, not an expression, so it cannot produce a value directly
+- leaves the `never` guard to you; tiny-pattern-ts is an expression and does not
+  need one
+
+The [TC39 pattern-matching proposal](https://github.com/tc39/proposal-pattern-matching)
+is still stage 1, so userland libraries remain the only option today.
+
 ## License
 
 MIT © 2026 tmu. See [LICENSE](./LICENSE).