Introduces watch/, a real Pebble watchapp (built via pebble build) that

shows the daily tarot/astrology reading on-device: persistence, reading
computation, and UI screens, driven by the existing engine/interpreter
code linked in unchanged where possible.

Required engine-side changes to make that linking work:
- A compact low-precision ephemeris (lowprec_ephemeris.c) replacing the
  vendored ~127KB Astronomy Engine, which doesn't fit the watch's ~64KB
  app budget.
- Hand-rolled sqrt/atan2/sin/cos replacements for that ephemeris and
  astro.c's Ascendant calculation - Pebble's statically-linked libm
  hard-faults on real hardware under this app's -fPIE link for all four.
- narrative.c/guidance.c refactored from FILE*/fprintf onto snprintf-
  based buffers, since Pebble's SDK blocks fprintf at compile time.

interpreter/src/guidance.c

@@ -1,5 +1,8 @@
 #include "guidance.h"
 
+#include <stdbool.h>
+#include <stdio.h>
+
 /* i18n_get() only - see narrative.c's own comment on why this one extra
  * engine header is needed despite guidance.h's otherwise header-only
  * engine dependency. */
@@ -137,13 +140,20 @@ static const char *reversed_marker(bool reversed) {
   return buf;
 }
 
-void guidance_print(FILE *out, const char *indent, const DailyInterpretation *interp,
+void guidance_write(char *buf, size_t buf_size, const char *indent, const DailyInterpretation *interp,
                      const CelticCrossSpread *spread) {
+  if (buf_size == 0) return;
+  buf[0] = '\0';
+
   const TarotDraw *attitude = &spread->positions[POSITION_ATTITUDE];
   const TarotDraw *outcome = &spread->positions[POSITION_OUTCOME];
 
+  /* Chained snprintf() calls, each bounds-checked against the running
+   * length before the next one runs - see narrative_write()'s matching
+   * comment for why (never fprintf/sprintf/vsnprintf). */
+  size_t len;
   if (interp->top_item_count == 0) {
-    fprintf(out, "%s%s\n", indent, no_transit_text(attitude->reversed));
+    len = (size_t)snprintf(buf, buf_size, "%s%s\n", indent, no_transit_text(attitude->reversed));
   } else {
     const Aspect *top = &interp->top_items[0].aspect;
     TransitCharacter character = classify_transit(top->type);
@@ -152,13 +162,18 @@ void guidance_print(FILE *out, const char *indent, const DailyInterpretation *in
     char intro[192];
     snprintf(intro, sizeof(intro), intro_template(interp->day_level),
              planet_display_name(top->transiting_planet));
-    fprintf(out, "%s%s %s\n", indent, intro, stance);
+    len = (size_t)snprintf(buf, buf_size, "%s%s %s\n", indent, intro, stance);
   }
+  if (len >= buf_size) return;
 
-  fprintf(out, "%s%s %s%s: %s\n", indent, i18n_get("guidance.attitude_intro", "Your Attitude card is"),
-          tarot_card_name(attitude->card), reversed_marker(attitude->reversed),
-          tarot_card_meaning(attitude->card, attitude->reversed));
-  fprintf(out, "%s%s %s%s: %s\n", indent, i18n_get("guidance.outcome_intro", "The spread's likely Outcome is"),
-          tarot_card_name(outcome->card), reversed_marker(outcome->reversed),
-          tarot_card_meaning(outcome->card, outcome->reversed));
+  len += (size_t)snprintf(buf + len, buf_size - len, "%s%s %s%s: %s\n", indent,
+                           i18n_get("guidance.attitude_intro", "Your Attitude card is"),
+                           tarot_card_name(attitude->card), reversed_marker(attitude->reversed),
+                           tarot_card_meaning(attitude->card, attitude->reversed));
+  if (len >= buf_size) return;
+
+  snprintf(buf + len, buf_size - len, "%s%s %s%s: %s\n", indent,
+           i18n_get("guidance.outcome_intro", "The spread's likely Outcome is"),
+           tarot_card_name(outcome->card), reversed_marker(outcome->reversed),
+           tarot_card_meaning(outcome->card, outcome->reversed));
 }

interpreter/src/guidance.h

@@ -1,7 +1,7 @@
 #ifndef DECK_GUIDANCE_H
 #define DECK_GUIDANCE_H
 
-#include <stdio.h>
+#include <stddef.h>
 
 /* Header-only dependency on the engine for struct/enum *definitions*,
  * same policy as narrative.h/significance.h - see their comments for
@@ -14,6 +14,13 @@
 #include "../../engine/src/tarot.h"
 #include "significance.h"
 
+/* Generous upper bound on guidance_write()'s output (intro/stance line
+ * + Attitude line + Outcome line, each ending in a newline, including
+ * the longest tarot_card_meaning() strings) across every language this
+ * project ships a translation for - see narrative.h's NARRATIVE_TEXT_MAX
+ * for the same reasoning. */
+#define GUIDANCE_TEXT_MAX 1024
+
 /* Ties the day's single most significant transit
  * (interp->top_items[0]) to the Celtic Cross spread, and prints a short
  * paragraph of concrete guidance on how to meet the day - the "combined
@@ -49,12 +56,18 @@
  * strings) is looked up via i18n_get() under "guidance.*" keys
  * (engine/i18n's .lang files) before falling back to the English text baked
  * into guidance.c, so it respects whatever --lang the caller loaded
- * with i18n_load() (main.c does so before calling this). The German
- * guidance.intro.* templates are deliberately phrased so the planet
- * name placeholder is always the sentence's grammatical subject
- * (nominative case) across all four day levels - see guidance.c's own
- * comment on k_intro_fallback. */
-void guidance_print(FILE *out, const char *indent, const DailyInterpretation *interp,
+ * with i18n_load()/i18n_load_table() (main.c does so before calling
+ * this). The German guidance.intro.* templates are deliberately phrased
+ * so the planet name placeholder is always the sentence's grammatical
+ * subject (nominative case) across all four day levels - see
+ * guidance.c's own comment on k_intro_fallback.
+ *
+ * Writes into `buf` (a caller-supplied buffer of `buf_size` bytes,
+ * always left null-terminated - GUIDANCE_TEXT_MAX is a safe size)
+ * instead of a FILE*, using only snprintf() internally (never
+ * fprintf/sprintf/vsnprintf, all of which Pebble's SDK blocks at compile
+ * time), so this function links into the watch app unchanged. */
+void guidance_write(char *buf, size_t buf_size, const char *indent, const DailyInterpretation *interp,
                      const CelticCrossSpread *spread);
 
 #endif

interpreter/src/main.c

@@ -1,5 +1,3 @@
-#define _POSIX_C_SOURCE 200809L /* for open_memstream */
-
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -156,27 +154,28 @@ static void print_body_in_sign_text(FILE *out, const PlanetPosition *pos) {
   fprintf(out, " %s", buf);
 }
 
-/* Captures narrative_print()/guidance_print()'s output (they only know
- * how to write to a FILE*) into a heap string, for embedding into JSON -
- * avoids changing either module's public API just for this one caller.
- * Strips a single trailing newline; caller must free() the result. */
+/* Captures narrative_write()/guidance_write()'s output into a heap
+ * string, for embedding into JSON - a stack buffer plus a single
+ * malloc()+memcpy() copy, since main.c doesn't need to stream this
+ * anywhere. Strips a single trailing newline; caller must free() the
+ * result. */
 static char *capture_narrative(const Aspect *aspect, int house) {
-  char *buf = NULL;
-  size_t size = 0;
-  FILE *mem = open_memstream(&buf, &size);
-  narrative_print(mem, "", aspect, house);
-  fclose(mem);
-  if (size > 0 && buf[size - 1] == '\n') buf[size - 1] = '\0';
+  char stack_buf[NARRATIVE_TEXT_MAX];
+  narrative_write(stack_buf, sizeof stack_buf, "", aspect, house);
+  size_t len = strlen(stack_buf);
+  if (len > 0 && stack_buf[len - 1] == '\n') stack_buf[--len] = '\0';
+  char *buf = malloc(len + 1);
+  memcpy(buf, stack_buf, len + 1);
   return buf;
 }
 
 static char *capture_guidance(const DailyInterpretation *interp, const CelticCrossSpread *spread) {
-  char *buf = NULL;
-  size_t size = 0;
-  FILE *mem = open_memstream(&buf, &size);
-  guidance_print(mem, "", interp, spread);
-  fclose(mem);
-  if (size > 0 && buf[size - 1] == '\n') buf[size - 1] = '\0';
+  char stack_buf[GUIDANCE_TEXT_MAX];
+  guidance_write(stack_buf, sizeof stack_buf, "", interp, spread);
+  size_t len = strlen(stack_buf);
+  if (len > 0 && stack_buf[len - 1] == '\n') stack_buf[--len] = '\0';
+  char *buf = malloc(len + 1);
+  memcpy(buf, stack_buf, len + 1);
   return buf;
 }
 
@@ -228,7 +227,11 @@ static void interp_print_text(FILE *out, const DailyReading *reading, const Dail
       print_body_in_sign_text(out, &reading->natal.bodies[a->natal_planet]);
       fprintf(out, " (%s %.1f\xc2\xb0, %s %.2f)\n", ui("ui.orb", "orb"), a->orb,
               ui("interp.score", "score"), item->score);
-      narrative_print(out, "     ", a, reading->transits.bodies[a->transiting_planet].house);
+
+      char narrative_buf[NARRATIVE_TEXT_MAX];
+      narrative_write(narrative_buf, sizeof narrative_buf, "     ", a,
+                       reading->transits.bodies[a->transiting_planet].house);
+      fputs(narrative_buf, out);
     }
   }
   fprintf(out, "\n");
@@ -236,7 +239,9 @@ static void interp_print_text(FILE *out, const DailyReading *reading, const Dail
   print_celtic_cross_text(out, &reading->spread);
   fprintf(out, "\n");
 
-  guidance_print(out, "", interp, &reading->spread);
+  char guidance_buf[GUIDANCE_TEXT_MAX];
+  guidance_write(guidance_buf, sizeof guidance_buf, "", interp, &reading->spread);
+  fputs(guidance_buf, out);
 }
 
 /* ===== --format html ===== */

interpreter/src/narrative.c

@@ -136,8 +136,11 @@ static const char *narrative_field(const char *slug, const char *field, const ch
   return i18n_get(key, fallback);
 }
 
-void narrative_print(FILE *out, const char *indent, const Aspect *aspect,
+void narrative_write(char *buf, size_t buf_size, const char *indent, const Aspect *aspect,
                       int transiting_house) {
+  if (buf_size == 0) return;
+  buf[0] = '\0';
+
   const TransitNarrative *n = &k_narratives[aspect->transiting_planet];
   const char *base = narrative_field(n->slug, "base", n->base);
 
@@ -147,7 +150,15 @@ void narrative_print(FILE *out, const char *indent, const Aspect *aspect,
 
   if (base[0] == '\0' && extra[0] == '\0') return;
 
-  fprintf(out, "%s", indent);
+  /* Chained snprintf() calls, each bounds-checked against the running
+   * length before the next one runs - never fprintf/sprintf/vsnprintf,
+   * all of which Pebble's SDK blocks at compile time (see narrative.h's
+   * doc comment). Once `len` reaches buf_size (truncated), every
+   * subsequent call is skipped rather than computing buf_size - len,
+   * which would underflow. */
+  size_t len = (size_t)snprintf(buf, buf_size, "%s", indent);
+  if (len >= buf_size) return;
+
   if (transiting_house >= 1 && transiting_house <= 12) {
     char house_key[24];
     snprintf(house_key, sizeof house_key, "narrative.house.%d", transiting_house);
@@ -156,9 +167,16 @@ void narrative_print(FILE *out, const char *indent, const Aspect *aspect,
     char frame[256];
     snprintf(frame, sizeof frame, i18n_get("narrative.house_frame", "In matters of %s (house %d)."),
              area, transiting_house);
-    fprintf(out, "%s ", frame);
+    len += (size_t)snprintf(buf + len, buf_size - len, "%s ", frame);
+    if (len >= buf_size) return;
   }
-  if (base[0] != '\0') fprintf(out, "%s", base);
-  if (extra[0] != '\0') fprintf(out, "%s%s", base[0] != '\0' ? " " : "", extra);
-  fprintf(out, "\n");
+  if (base[0] != '\0') {
+    len += (size_t)snprintf(buf + len, buf_size - len, "%s", base);
+    if (len >= buf_size) return;
+  }
+  if (extra[0] != '\0') {
+    len += (size_t)snprintf(buf + len, buf_size - len, "%s%s", base[0] != '\0' ? " " : "", extra);
+    if (len >= buf_size) return;
+  }
+  snprintf(buf + len, buf_size - len, "\n");
 }

interpreter/src/narrative.h

@@ -1,12 +1,20 @@
 #ifndef DECK_NARRATIVE_H
 #define DECK_NARRATIVE_H
 
-#include <stdio.h>
+#include <stddef.h>
 
 /* Header-only dependency on the engine, same policy as significance.h -
  * see its comment for why. */
 #include "../../engine/src/astro.h"
 
+/* Generous upper bound on narrative_write()'s output (indent + house
+ * framing + base + harmonious/discordant addendum + newline) across
+ * every language this project ships a translation for - callers on
+ * constrained platforms (the watch) are free to size their own stack
+ * buffer smaller if they know their own strings are shorter; this is
+ * just a safe default for a caller that doesn't want to think about it. */
+#define NARRATIVE_TEXT_MAX 512
+
 /* Condensed, public-domain descriptions of what each transiting planet
  * classically signifies, sourced from Sepharial's "Transits and
  * Planetary Periods" (1920, public domain - res/Transits_and_Planetary_
@@ -22,15 +30,19 @@
  * narrative.c is original, written for this project in a matching
  * voice, not drawn from Sepharial.
  *
- * Prints a narrative sentence for `aspect`'s transiting planet to `out`,
- * indented with `indent` and followed by a newline - or prints nothing
- * if the source material has no text applicable to this planet/aspect
+ * Writes a narrative sentence for `aspect`'s transiting planet into
+ * `buf` (a caller-supplied buffer of `buf_size` bytes, always left
+ * null-terminated - NARRATIVE_TEXT_MAX is a safe size), indented with
+ * `indent` and followed by a newline - or writes an empty string if the
+ * source material has no text applicable to this planet/aspect
  * combination (e.g. an exactly neutral conjunction to a planet whose
  * only text is a "well/badly aspected" addendum, like the Sun). A
  * conjunction is treated as neutral - neither the "harmonious" nor the
  * "discordant" addendum is shown for it - since Sepharial's own text
  * says a conjunction "takes the nature of what it conjoins," something
- * this data doesn't model.
+ * this data doesn't model. Uses only snprintf() internally (never
+ * fprintf/sprintf/vsnprintf, all of which Pebble's SDK blocks at compile
+ * time), so this function links into the watch app unchanged.
  *
  * `transiting_house` is the whole-sign house (1-12) the transiting
  * planet currently occupies in the natal chart - i.e.
@@ -44,9 +56,9 @@
  * Every string here is looked up via i18n_get() under "narrative.*"
  * keys (engine/i18n's .lang files) before falling back to the English text
  * baked into narrative.c, the same catalog tarot_data.c uses - so this
- * text respects whatever --lang the caller loaded with i18n_load()
- * (main.c does so before calling this). */
-void narrative_print(FILE *out, const char *indent, const Aspect *aspect,
+ * text respects whatever --lang the caller loaded with i18n_load()/
+ * i18n_load_table() (main.c does so before calling this). */
+void narrative_write(char *buf, size_t buf_size, const char *indent, const Aspect *aspect,
                       int transiting_house);
 
 #endif

interpreter/tests/guidance_test.c

@@ -1,6 +1,7 @@
 #define _POSIX_C_SOURCE 200809L /* for mkstemp/fdopen */
 
 #include <assert.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -9,15 +10,6 @@
 #include "../../engine/src/i18n.h"
 #include "../src/guidance.h"
 
-static const char *slurp(FILE *f) {
-  static char buf[4096];
-  long len = ftell(f);
-  rewind(f);
-  size_t n = fread(buf, 1, (size_t)len, f);
-  buf[n] = '\0';
-  return buf;
-}
-
 static DailyInterpretation make_interp(DaySignificance level, AspectType type, Body transiting) {
   DailyInterpretation interp;
   interp.top_item_count = 1;
@@ -51,9 +43,8 @@ static CelticCrossSpread make_spread(TarotCard attitude_card, bool attitude_reve
 static void test_harmonious_upright(void) {
   DailyInterpretation interp = make_interp(DAY_MAJOR, ASPECT_TRINE, PLANET_JUPITER);
   CelticCrossSpread spread = make_spread(CARD_SUN, false, CARD_WORLD, false);
-  FILE *f = tmpfile();
-  guidance_print(f, "", &interp, &spread);
-  const char *text = slurp(f);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "already meeting the day in the right spirit") != NULL);
   assert(strstr(text, "Jupiter") != NULL);
@@ -61,39 +52,34 @@ static void test_harmonious_upright(void) {
   assert(strstr(text, "The World: Assured success") != NULL);
   assert(strstr(text, "(Reversed)") == NULL);
 
-  fclose(f);
   printf("PASS test_harmonious_upright\n");
 }
 
 static void test_discordant_reversed(void) {
   DailyInterpretation interp = make_interp(DAY_MAJOR, ASPECT_SQUARE, PLANET_SATURN);
   CelticCrossSpread spread = make_spread(CARD_DEVIL, true, CARD_WORLD, false);
-  FILE *f = tmpfile();
-  guidance_print(f, "", &interp, &spread);
-  const char *text = slurp(f);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "Both the day and your own footing are unsettled") != NULL);
   assert(strstr(text, "Saturn") != NULL);
   assert(strstr(text, "The Devil (Reversed): Evil fatality") != NULL);
   assert(strstr(text, "The World: Assured success") != NULL);
 
-  fclose(f);
   printf("PASS test_discordant_reversed\n");
 }
 
 static void test_neutral_conjunction_upright(void) {
   DailyInterpretation interp = make_interp(DAY_MAJOR, ASPECT_CONJUNCTION, PLANET_PLUTO);
   CelticCrossSpread spread = make_spread(CARD_EMPEROR, false, CARD_MOON, true);
-  FILE *f = tmpfile();
-  guidance_print(f, "", &interp, &spread);
-  const char *text = slurp(f);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "Today concentrates whatever you already bring to it") != NULL);
   assert(strstr(text, "Pluto") != NULL);
   assert(strstr(text, "The Emperor: Stability, power") != NULL);
   assert(strstr(text, "The Moon (Reversed): Instability, inconstancy") != NULL);
 
-  fclose(f);
   printf("PASS test_neutral_conjunction_upright\n");
 }
 
@@ -104,74 +90,64 @@ static void test_neutral_conjunction_upright(void) {
 static void test_significant_day_uses_significant_intro(void) {
   DailyInterpretation interp = make_interp(DAY_SIGNIFICANT, ASPECT_SEXTILE, PLANET_VENUS);
   CelticCrossSpread spread = make_spread(CARD_STAR, false, CARD_SUN, false);
-  FILE *f = tmpfile();
-  guidance_print(f, "", &interp, &spread);
-  const char *text = slurp(f);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "clearly active today") != NULL);
   assert(strstr(text, "Venus") != NULL);
 
-  fclose(f);
   printf("PASS test_significant_day_uses_significant_intro\n");
 }
 
 static void test_notable_day_uses_notable_intro(void) {
   DailyInterpretation interp = make_interp(DAY_NOTABLE, ASPECT_SEXTILE, PLANET_MARS);
   CelticCrossSpread spread = make_spread(CARD_STAR, false, CARD_SUN, false);
-  FILE *f = tmpfile();
-  guidance_print(f, "", &interp, &spread);
-  const char *text = slurp(f);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "mild touch from Mars") != NULL);
 
-  fclose(f);
   printf("PASS test_notable_day_uses_notable_intro\n");
 }
 
 static void test_quiet_day_with_a_faint_item_still_names_it(void) {
   DailyInterpretation interp = make_interp(DAY_QUIET, ASPECT_SEXTILE, PLANET_MERCURY);
   CelticCrossSpread spread = make_spread(CARD_STAR, false, CARD_SUN, false);
-  FILE *f = tmpfile();
-  guidance_print(f, "", &interp, &spread);
-  const char *text = slurp(f);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "only faintly active today") != NULL);
   assert(strstr(text, "Mercury") != NULL);
 
-  fclose(f);
   printf("PASS test_quiet_day_with_a_faint_item_still_names_it\n");
 }
 
 static void test_no_aspects_at_all_falls_back_to_attitude_only(void) {
   DailyInterpretation interp = make_empty_interp();
   CelticCrossSpread spread = make_spread(CARD_STAR, false, CARD_SUN, false);
-  FILE *f = tmpfile();
-  guidance_print(f, "", &interp, &spread);
-  const char *text = slurp(f);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "astrologically quiet day") != NULL);
   assert(strstr(text, "trust your current footing") != NULL);
   assert(strstr(text, "The Star: Loss, theft") != NULL);
   assert(strstr(text, "The Sun: Material happiness") != NULL);
 
-  fclose(f);
   printf("PASS test_no_aspects_at_all_falls_back_to_attitude_only\n");
 }
 
 static void test_no_aspects_at_all_respects_reversed_attitude(void) {
   DailyInterpretation interp = make_empty_interp();
   CelticCrossSpread spread = make_spread(CARD_STAR, true, CARD_SUN, false);
-  FILE *f = tmpfile();
-  guidance_print(f, "", &interp, &spread);
-  const char *text = slurp(f);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "quietly re-settle your own footing") != NULL);
 
-  fclose(f);
   printf("PASS test_no_aspects_at_all_respects_reversed_attitude\n");
 }
 
-/* Proves guidance_print() actually routes through i18n_get() rather
+/* Proves guidance_write() actually routes through i18n_get() rather
  * than just printing the hardcoded fallback. Run last: i18n_load()
  * replaces the process-global catalog for the rest of the binary's
  * lifetime. */
@@ -191,16 +167,14 @@ static void test_translation_catalog_overrides_fallback_text(void) {
 
   DailyInterpretation interp = make_interp(DAY_MAJOR, ASPECT_SQUARE, PLANET_SATURN);
   CelticCrossSpread spread = make_spread(CARD_SUN, false, CARD_WORLD, false);
-  FILE *out = tmpfile();
-  guidance_print(out, "", &interp, &spread);
-  const char *text = slurp(out);
+  char text[GUIDANCE_TEXT_MAX];
+  guidance_write(text, sizeof text, "", &interp, &spread);
 
   assert(strstr(text, "UEBERSETZTE HALTUNG") != NULL);
   assert(strstr(text, "UEBERSETZTE EINLEITUNG UEBERSETZTER SATURN") != NULL);
   assert(strstr(text, "UEBERSETZTE HALTUNGSKARTE") != NULL);
   assert(strstr(text, "Your instincts are sound") == NULL); /* English fallback must not leak through */
 
-  fclose(out);
   printf("PASS test_translation_catalog_overrides_fallback_text\n");
 }
 

interpreter/tests/narrative_test.c

@@ -9,115 +9,92 @@
 #include "../../engine/src/i18n.h"
 #include "../src/narrative.h"
 
-static const char *slurp(FILE *f) {
-  static char buf[4096];
-  long len = ftell(f);
-  rewind(f);
-  size_t n = fread(buf, 1, (size_t)len, f);
-  buf[n] = '\0';
-  return buf;
-}
-
 static void test_hard_aspect_shows_base_but_not_harmonious_bonus(void) {
   Aspect a = { .transiting_planet = PLANET_SATURN, .natal_planet = PLANET_MOON,
                .type = ASPECT_SQUARE, .orb = 1.0 };
-  FILE *f = tmpfile();
-  narrative_print(f, "  ", &a, 0);
-  const char *text = slurp(f);
+  char text[NARRATIVE_TEXT_MAX];
+  narrative_write(text, sizeof text, "  ", &a, 0);
 
   assert(strstr(text, "depression") != NULL);
   assert(strstr(text, "past associations") == NULL);
 
-  fclose(f);
   printf("PASS test_hard_aspect_shows_base_but_not_harmonious_bonus\n");
 }
 
 static void test_soft_aspect_adds_harmonious_bonus(void) {
   Aspect a = { .transiting_planet = PLANET_SATURN, .natal_planet = PLANET_SUN,
                .type = ASPECT_TRINE, .orb = 1.0 };
-  FILE *f = tmpfile();
-  narrative_print(f, "  ", &a, 0);
-  const char *text = slurp(f);
+  char text[NARRATIVE_TEXT_MAX];
+  narrative_write(text, sizeof text, "  ", &a, 0);
 
   assert(strstr(text, "depression") != NULL);
   assert(strstr(text, "past associations") != NULL);
 
-  fclose(f);
   printf("PASS test_soft_aspect_adds_harmonious_bonus\n");
 }
 
 static void test_conjunction_is_neutral_prints_base_only(void) {
   Aspect a = { .transiting_planet = PLANET_SATURN, .natal_planet = PLANET_SUN,
                .type = ASPECT_CONJUNCTION, .orb = 1.0 };
-  FILE *f = tmpfile();
-  narrative_print(f, "  ", &a, 0);
-  const char *text = slurp(f);
+  char text[NARRATIVE_TEXT_MAX];
+  narrative_write(text, sizeof text, "  ", &a, 0);
 
   assert(strstr(text, "depression") != NULL);
   assert(strstr(text, "past associations") == NULL);
 
-  fclose(f);
   printf("PASS test_conjunction_is_neutral_prints_base_only\n");
 }
 
 /* The Sun has no unconditional base text (see narrative.c) - a neutral
- * conjunction to it should print nothing at all. */
+ * conjunction to it should write nothing at all. */
 static void test_empty_base_and_neutral_aspect_prints_nothing(void) {
   Aspect a = { .transiting_planet = PLANET_SUN, .natal_planet = PLANET_MOON,
                .type = ASPECT_CONJUNCTION, .orb = 1.0 };
-  FILE *f = tmpfile();
-  narrative_print(f, "  ", &a, 0);
-  long len = ftell(f);
+  char text[NARRATIVE_TEXT_MAX];
+  narrative_write(text, sizeof text, "  ", &a, 0);
 
-  assert(len == 0);
+  assert(text[0] == '\0');
 
-  fclose(f);
   printf("PASS test_empty_base_and_neutral_aspect_prints_nothing\n");
 }
 
 static void test_discordant_aspect_on_empty_base_planet(void) {
   Aspect a = { .transiting_planet = PLANET_SUN, .natal_planet = PLANET_MOON,
                .type = ASPECT_OPPOSITION, .orb = 1.0 };
-  FILE *f = tmpfile();
-  narrative_print(f, "  ", &a, 0);
-  const char *text = slurp(f);
+  char text[NARRATIVE_TEXT_MAX];
+  narrative_write(text, sizeof text, "  ", &a, 0);
 
   assert(strstr(text, "Degradation") != NULL);
 
-  fclose(f);
   printf("PASS test_discordant_aspect_on_empty_base_planet\n");
 }
 
 static void test_known_house_adds_area_framing(void) {
   Aspect a = { .transiting_planet = PLANET_SATURN, .natal_planet = PLANET_MOON,
                .type = ASPECT_SQUARE, .orb = 1.0 };
-  FILE *f = tmpfile();
-  narrative_print(f, "  ", &a, 3);
-  const char *text = slurp(f);
+  char text[NARRATIVE_TEXT_MAX];
+  narrative_write(text, sizeof text, "  ", &a, 3);
 
   assert(strstr(text, "house 3") != NULL);
   assert(strstr(text, "communication") != NULL);
   assert(strstr(text, "depression") != NULL);
 
-  fclose(f);
   printf("PASS test_known_house_adds_area_framing\n");
 }
 
 static void test_unknown_house_omits_area_framing(void) {
   Aspect a = { .transiting_planet = PLANET_SATURN, .natal_planet = PLANET_MOON,
                .type = ASPECT_SQUARE, .orb = 1.0 };
-  FILE *f = tmpfile();
-  narrative_print(f, "  ", &a, 0); /* 0 = "no data" sentinel, not a real house */
-  const char *text = slurp(f);
+  char text[NARRATIVE_TEXT_MAX];
+  narrative_write(text, sizeof text, "  ", &a, 0); /* 0 = "no data" sentinel, not a real house */
 
   assert(strstr(text, "house") == NULL);
   assert(strstr(text, "depression") != NULL);
 
-  fclose(f);
   printf("PASS test_unknown_house_omits_area_framing\n");
 }
 
-/* Proves narrative_print() actually routes through i18n_get() rather
+/* Proves narrative_write() actually routes through i18n_get() rather
  * than just printing the hardcoded fallback - loads a translation file
  * that overrides one planet's base text and one house's area text, and
  * checks the override wins. Run last: i18n_load() replaces the
@@ -136,15 +113,13 @@ static void test_translation_catalog_overrides_fallback_text(void) {
 
   Aspect a = { .transiting_planet = PLANET_SATURN, .natal_planet = PLANET_MOON,
                .type = ASPECT_CONJUNCTION, .orb = 1.0 };
-  FILE *out = tmpfile();
-  narrative_print(out, "", &a, 3);
-  const char *text = slurp(out);
+  char text[NARRATIVE_TEXT_MAX];
+  narrative_write(text, sizeof text, "", &a, 3);
 
   assert(strstr(text, "UEBERSETZTER SATURN TEXT") != NULL);
   assert(strstr(text, "UEBERSETZTES HAUS DREI") != NULL);
   assert(strstr(text, "depression") == NULL); /* English fallback must not leak through */
 
-  fclose(out);
   printf("PASS test_translation_catalog_overrides_fallback_text\n");
 }