diff --git a/plans/prolog-on-sx.md b/plans/prolog-on-sx.md
index 2bd3efe0..152d1ea1 100644
--- a/plans/prolog-on-sx.md
+++ b/plans/prolog-on-sx.md
@@ -81,13 +81,14 @@ Representation choices (finalise in phase 1, document here):
 - [x] Drive scoreboard to 200+
 
 ### Phase 7 — compiler (later, optional)
-- [ ] Compile clauses to SX continuations for speed
+- [x] Compile clauses to SX continuations for speed
 - [ ] Keep interpreter as the reference
 
 ## Progress log
 
 _Newest first. Agent appends on every commit._
 
+- 2026-04-25 — Clause compiler (`lib/prolog/compiler.sx`): `pl-compile-clause` converts parse-AST clauses to SX closures `(fn (goal trail db cut-box k) bool)`. Pre-collects var names at compile time; `pl-cmp-build-term` reconstructs fresh runtime terms per call. `pl-compile-db!` compiles all clauses in a DB and stores them in `:compiled` table. `pl-solve-user!` in runtime.sx auto-dispatches to compiled lambdas when present, falls back to interpreted. `pl-try-compiled-clauses!` mirrors `pl-try-clauses!` cut semantics. 17 tests in `tests/compiler.sx`. Total **534** (+17).
 - 2026-04-25 — `predsort/3` (insertion-sort with 3-arg comparator predicate, deduplicates `=` pairs), `term_variables/2` (collect unbound vars left-to-right, dedup by id), arithmetic extensions (`floor/1`, `ceiling/1`, `truncate/1`, `round/1`, `sign/1`, `sqrt/1`, `pow/2`, `**/2`, `^/2`, `integer/1`, `float/1`, `float_integer_part/1`, `float_fractional_part/1`). 21 tests in `tests/advanced.sx`. Total **517** (+21).
 - 2026-04-25 — `sub_atom/5` (non-deterministic substring enumeration; CPS loop over all (start,sublen) pairs; trail-undo only on backtrack) + `aggregate_all/3` (6 templates: count/bag/sum/max/min/set; uses `pl-collect-solutions`). 25 tests in `tests/string_agg.sx`. Total **496** (+25).
 - 2026-04-25 — `:-` operator + assert with rules: added `(list ":-" 1200 "xfx")` to `pl-op-table`; fixed `pl-token-op` to accept `"op"` token type (tokenizer emits `:-` as `"op"`, not `"atom"`). `pl-build-clause` already handled `("compound" ":-" ...)`. `assert((head :- body))` now works for facts+rules. 15 tests in `tests/assert_rules.sx`. Total **471** (+15).