G3b packet 1: CreateMeasure reaches the wire, the mint, and the grid oracle

Kind and tag 39 at schema-minor epoch 12, in both unaligned discriminant
spaces. Measure is schema major 0 -- struct_codec! is a plain walk and
TimeAnchor's Codec has no version branching -- so schema_major() gains no arm
and OperationEnvelopeBlock stays at 3.

CreateMeasure is a nested-container mint following CreateStaffInstance, not
G3a's root-level shape: it carries the owning StaffInstanceId beside the
value, and measure_values carries that parent because Measure has no
back-pointer and the graph-removal arm will need it. Append-only, with
referential preconditions on the parent, the signature, and every non-wall-clock
start referent.

The comparable relation is five exact shapes with an identical boundary
selector; ordering across Start/End is unsound while measure length is
unresolved, so it stays unverifiable. Boundary distance needs a musical delta,
which only same-referent same-selector Musical offsets supply. The effective-grid
oracle reconstructs inheritance from metric_grid_chain and meter_change_chain by
write recency -- not by always overlaying per-key on whole-grid -- folds in
prospective overrides, and runs identically in both reduction modes, so an
instance_grid ledger keeps base-free reduction honest.

Three precondition reasons at 16-18. Repairs a live bug found in review: the
materialized-effect decoder stopped at 13, so reasons 14 and 15 already encoded
without decoding, and the generator drawing below(14) could not see them.

Executed against spec/CONTRACT_GENESIS_G3B_MEASURE.md, mutations M1-M33,
M64-M66, M67-M70. text_projection.tex moved into this packet: four tests read
it live, so the companion bump cannot be split from the grammar.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QjsEnYhm1gPpf6ii2iFxFV

crates/epiphany-core/src/codec.rs

@@ -3598,6 +3598,14 @@ canonical_value! {
     PartDefinition,
     AnalysisLayer,
     ViewDefinition,
+    // Genesis tranche G3b (`CONTRACT_GENESIS_G3B_MEASURE.md` pin 3) —
+    // CreateMeasure embeds the full value, mirroring CreateStaffInstance's
+    // `StaffInstance`. `Measure` already has a `Codec` (`struct_codec!` at
+    // `:1825`) and already ships inside `Score`; this makes that existing
+    // layout reachable per-value, same as every other entry here. No new wire
+    // layout, and no `textvalue_graph.rs` work — `struct_codec!` already
+    // generated `Measure`'s `TextValue` impl alongside its `Codec`.
+    Measure,
 }
 
 #[cfg(test)]
@@ -3926,6 +3934,128 @@ mod tests {
         assert!(back.accidental_extensions.is_empty());
     }
 
+    /// Genesis tranche G3b (`CONTRACT_GENESIS_G3B_MEASURE.md` pin 4, M12):
+    /// pins the exact frozen bytes of `Measure`'s `struct_codec!` wire form
+    /// (`id, start, time_signature, explicit_number, number_visibility`).
+    ///
+    /// The five field values are chosen so their encodings are MUTUALLY
+    /// DISTINCT in length (contract §3's `valuegen` trap, from G3a's
+    /// `analysis_layer` mistake where a same-width field pair made a
+    /// field-swap byte-invisible): `id` is a 20-byte id-leaf, `start` (a
+    /// `WallClock` anchor) is 13 bytes, `time_signature` (`Some`) is a
+    /// 21-byte id-leaf, `explicit_number` (`Some`) is a bare 5-byte `u32`,
+    /// and `number_visibility` is a 1-byte C-style enum tag.
+    ///
+    /// **Mutation:** reorder `struct_codec!(Measure { ... })`'s field list in
+    /// this file; must fail — a `struct_codec!` field reorder changes encode
+    /// and decode symmetrically and stays green under a round-trip-only
+    /// assertion, which is why this pins literal bytes instead.
+    #[test]
+    fn genesis_g3b_measure_wire_bytes_are_frozen() {
+        use crate::graph::{Measure, MeasureNumberVisibility};
+        use crate::ids::{MeasureId, ReplicaId, TimeSignatureId};
+        use crate::time::{TimeAnchor, WallClockTime};
+
+        fn hex(bytes: &[u8]) -> String {
+            bytes.iter().map(|b| format!("{b:02x}")).collect()
+        }
+
+        let measure = Measure {
+            id: MeasureId::new(ReplicaId(1), 2),
+            start: TimeAnchor::WallClock {
+                time: WallClockTime(3),
+            },
+            time_signature: Some(TimeSignatureId::new(ReplicaId(1), 4)),
+            explicit_number: Some(5),
+            number_visibility: MeasureNumberVisibility::Always,
+        };
+        let mut bytes = Vec::new();
+        measure.enc(&mut bytes);
+        let expected = "100000000000000000000001000000000000000203080000000300000000000000011000000000000000000000010000000000000004010500000001";
+        assert_eq!(hex(&bytes), expected, "the Measure wire form moved");
+        assert!(!bytes.is_empty());
+
+        let decoded = Measure::dec(&mut Reader::new(&bytes)).expect("golden decodes");
+        assert_eq!(decoded, measure);
+    }
+
+    /// Genesis tranche G3b (M14): the strict per-value re-encode comparison
+    /// in `canonical_value!` is the ONLY thing standing between an
+    /// unreduced `RationalTime` spelling and acceptance.
+    ///
+    /// `Measure.start` carries an `Event`-anchored `Musical` offset whose
+    /// `RationalTime` is spelled UNREDUCED, `2/4`. `RationalTime::dec` ends in
+    /// `BigRational::new`, which reduces on construction, so the decoded
+    /// value is `1/2`; re-encoding it then emits `1/2`'s magnitudes, which
+    /// differ from the fed-in `2/4` bytes. A structurally-decodable but
+    /// NONCANONICAL encoding — exactly what the strict per-value check
+    /// (decode → `finish()` → re-encode → reject on mismatch) exists to
+    /// reject.
+    ///
+    /// **Mutation:** in `canonical_value!`, remove the
+    /// `v.canonical_bytes() != bytes` check (return `Ok(v)` unconditionally);
+    /// must fail. NOT "remove `Measure` from `canonical_value!`" — that does
+    /// not compile: the ops-crate envelope decode arm calls `value::<Measure>`,
+    /// bound by `T: CanonicalValue`.
+    #[test]
+    fn genesis_g3b_measure_start_rejects_an_unreduced_rational_time() {
+        use crate::graph::{Measure, MeasureNumberVisibility};
+        use crate::ids::{EventId, MeasureId, ReplicaId};
+        use crate::time::{AnchorOffset, MusicalDuration, RationalTime, TimeAnchor};
+
+        // The canonical (reduced) 1/2 value this rung's fixture decodes to.
+        let reduced = Measure {
+            id: MeasureId::new(ReplicaId(1), 2),
+            start: TimeAnchor::Event {
+                id: EventId::new(ReplicaId(1), 3),
+                offset: AnchorOffset::Musical(MusicalDuration(
+                    RationalTime::new(1, 2).expect("1/2 is representable"),
+                )),
+            },
+            time_signature: None,
+            explicit_number: None,
+            number_visibility: MeasureNumberVisibility::Auto,
+        };
+        let mut good_bytes = Vec::new();
+        reduced.enc(&mut good_bytes);
+
+        // The RationalTime wire pattern for 1/2 (Plus sign, 1-byte numerator
+        // magnitude `01`, 1-byte denominator magnitude `02`) and its
+        // UNREDUCED 2/4 counterpart — same byte length (11), so substituting
+        // one for the other does not disturb any surrounding length prefix.
+        let pattern_1_2: [u8; 11] = [1, 1, 0, 0, 0, 0x01, 1, 0, 0, 0, 0x02];
+        let pattern_2_4: [u8; 11] = [1, 1, 0, 0, 0, 0x02, 1, 0, 0, 0, 0x04];
+
+        let occurrences = good_bytes
+            .windows(pattern_1_2.len())
+            .filter(|w| *w == pattern_1_2)
+            .count();
+        assert_eq!(
+            occurrences, 1,
+            "the 1/2 RationalTime pattern must appear exactly once, to substitute unambiguously"
+        );
+        let at = good_bytes
+            .windows(pattern_1_2.len())
+            .position(|w| w == pattern_1_2)
+            .unwrap();
+        let mut bad_bytes = good_bytes.clone();
+        bad_bytes[at..at + pattern_2_4.len()].copy_from_slice(&pattern_2_4);
+        assert_eq!(bad_bytes.len(), good_bytes.len());
+
+        // The reduced (canonical) bytes round-trip.
+        assert_eq!(
+            Measure::decode_canonical(&good_bytes).as_ref(),
+            Ok(&reduced)
+        );
+        // The unreduced (2/4) bytes are structurally decodable (RationalTime
+        // itself never rejects an unreduced input — it normalizes), but the
+        // outer strict re-encode comparison MUST reject them.
+        assert!(
+            Measure::decode_canonical(&bad_bytes).is_err(),
+            "an unreduced RationalTime spelling must be rejected by the strict re-encode check"
+        );
+    }
+
     /// Genesis tranche G2b (`CONTRACT_GENESIS_G2B_TUNING.md` §1, pin/touch-row
     /// 3): `TuningContextSettings`'s canonical encoding is **byte-identical**
     /// to `ScoreTuningContext`'s existing five-field walk — a type-level

crates/epiphany-core/src/graph.rs

@@ -584,6 +584,19 @@ impl Voice {
 
 /// A measure belonging to exactly one staff instance (Chapter 5
 /// §"Staff-Based Content").
+///
+/// Genesis tranche G3b (`spec/CONTRACT_GENESIS_G3B_MEASURE.md`): `CreateMeasure`
+/// is the sole authoring path, and it is append-only — a measure is always
+/// pushed at the end of the owning [`StaffInstance::measures`], never
+/// inserted. `time_signature: None` means *inherit* the effective grid's
+/// active signature at this measure's start; that inherited meter still
+/// governs boundary consistency (invariant 20's second clause) even though
+/// `None` exempts a measure from the first clause (agreement). Invariant 20's
+/// agreement and boundary checks ABSTAIN — emit no violation — where the
+/// comparison or delta they need is not computable (contract pin 7): this is
+/// deliberate, not a safety property, because base-ingested data may predate
+/// the rule. Pickup/anacrusis (a partial first measure) is deferred
+/// (P13-S19) and is never refused or flagged by this rung.
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct Measure {
     pub id: MeasureId,
@@ -607,7 +620,9 @@ pub struct StaffInstance {
     pub key_sequence: Vec<KeySignatureChange>,
     pub local_metric_grid: Option<MetricGrid>,
     /// Measures belonging to this instance, in order (per-staff; admits
-    /// polymeter).
+    /// polymeter). Append-only: `CreateMeasure` (genesis tranche G3b) always
+    /// pushes at the end, gated on the effective grid's agreement and
+    /// boundary-distance preconditions (contract pin 9).
     pub measures: Vec<Measure>,
     pub instrument_override: Option<InstrumentId>,
     pub staff_lines_override: Option<StaffLineConfiguration>,

crates/epiphany-editor-core/src/barriers.rs

@@ -466,6 +466,17 @@ pub(crate) fn subjects_of(kind: &OperationKind, score: &Score) -> BarrierSubject
         OperationKind::CreateView(op) => {
             one(TypedObjectId::View(op.view_id()), EditContext::default())
         }
+        // Genesis tranche G3b: `Measure` is a nested container child of a
+        // `StaffInstance` (not a root-level entity like the mints above), so
+        // — exactly like `CreateVoice` — it names the region/staff-instance
+        // context its parent resolves to.
+        OperationKind::CreateMeasure(op) => one(
+            TypedObjectId::Measure(op.measure_id()),
+            ctx(
+                region_of_staff_instance(score, op.instance),
+                Some(op.instance),
+            ),
+        ),
         OperationKind::SetTimeSignature(op) => {
             let mut objects = vec![(TypedObjectId::Region(op.region), ctx(Some(op.region), None))];
             if let Some(signature) = &op.time_signature {

crates/epiphany-layout-ir/src/barrier.rs

@@ -1153,30 +1153,32 @@ mod tests {
                 tag: 7
             })
         );
-        // Operation-kind tag 39 is one past the vocabulary (the Phase-3 ops
+        // Operation-kind tag 40 is one past the vocabulary (the Phase-3 ops
         // tranche appended 24..=27, the repeat pair 28/29, `TransposeInterval`
         // 30, genesis G1's `CreateInstrument` 31, genesis G2a's
         // `SetCanvasLayoutDefaults` 32 and `SetSpellingPrecedence` 33,
         // genesis G2b's `SetTuningContext` 34, genesis G3a's
         // `CreateStaffGroup`/`CreatePartDefinition`/`CreateAnalysisLayer`/
-        // `CreateView` 35..=38; encodings are append-only).
+        // `CreateView` 35..=38, genesis G3b's `CreateMeasure` 39; encodings
+        // are append-only).
         //
         // This assertion named 30 until Push 5 / P4, 31 until genesis G1, 32
-        // until genesis G2a, 34 until genesis G2b, and 35 until genesis G3a —
+        // until genesis G2a, 34 until genesis G2b, 35 until genesis G3a, and
-        // each time, by then, the number had become a real kind, so the test
+        // 39 until genesis G3b — each time, by then, the number had become a
-        // was pinning a bug: a barrier that prohibited the new operation
+        // real kind, so the test was pinning a bug: a barrier that
-        // encoded fine and would not read back. It must be bumped by every
+        // prohibited the new operation encoded fine and would not read back.
-        // tranche that appends a tag, and it is deliberately a literal rather
+        // It must be bumped by every tranche that appends a tag, and it is
-        // than `PAYLOAD_FREE.len()` so the bump is a conscious act.
+        // deliberately a literal rather than `PAYLOAD_FREE.len()` so the bump
+        // is a conscious act.
         let mut bytes = vec![0u8];
         bytes.extend(set_blob(&[]));
-        bytes.extend(set_blob(&[vec![39u8]]));
+        bytes.extend(set_blob(&[vec![40u8]]));
         bytes.push(0);
         assert_eq!(
             EditBarrier::decode_canonical_bytes(&bytes),
             Err(BarrierDecodeError::InvalidTag {
                 kind: "OperationKindTag",
-                tag: 39
+                tag: 40
             })
         );
     }

crates/epiphany-ops/src/decode.rs

@@ -223,6 +223,14 @@ fn precondition_reason(reader: &mut Reader<'_>) -> Result<PreconditionFailureRea
         11 => Ok(PreconditionFailureReason::TempoMapMalformed),
         12 => Ok(PreconditionFailureReason::SystemDerivedContentImmutable),
         13 => Ok(PreconditionFailureReason::RecreateContentMismatch),
+        // Additive (Push 4a); a pre-existing decoder hole (P13-S20) — these
+        // two encode but could not decode until this rung.
+        14 => Ok(PreconditionFailureReason::AcousticRealizationPinned),
+        15 => Ok(PreconditionFailureReason::TranspositionOutOfRange),
+        // Additive (Genesis tranche G3b).
+        16 => Ok(PreconditionFailureReason::MeasureMeterMismatch),
+        17 => Ok(PreconditionFailureReason::MeasureOutOfOrder),
+        18 => Ok(PreconditionFailureReason::MeasureOrderUnverifiable),
         tag => Err(MaterializedDecodeError::InvalidTag {
             kind: "PreconditionFailureReason",
             tag,
@@ -618,10 +626,38 @@ mod tests {
             ReanchorReason::SameCanvasNearer
         );
         // The vocabularies stay bounded: one past the append rejects.
-        assert!(exact(&[14], precondition_reason).is_err());
+        assert!(exact(&[19], precondition_reason).is_err());
         assert!(exact(&[7], reanchor_reason).is_err());
     }
 
+    /// Genesis tranche G3b (contract row 12a / M64–M66): reasons 14 and 15
+    /// (Push 4a's `AcousticRealizationPinned`/`TranspositionOutOfRange`) were
+    /// a pre-existing decoder hole — they encoded but could not decode
+    /// (P13-S20) — and this rung's own 16–18 must decode too.
+    #[test]
+    fn genesis_g3b_and_the_p13_s20_hole_decode() {
+        assert_eq!(
+            exact(&[14], precondition_reason).unwrap(),
+            PreconditionFailureReason::AcousticRealizationPinned
+        );
+        assert_eq!(
+            exact(&[15], precondition_reason).unwrap(),
+            PreconditionFailureReason::TranspositionOutOfRange
+        );
+        assert_eq!(
+            exact(&[16], precondition_reason).unwrap(),
+            PreconditionFailureReason::MeasureMeterMismatch
+        );
+        assert_eq!(
+            exact(&[17], precondition_reason).unwrap(),
+            PreconditionFailureReason::MeasureOutOfOrder
+        );
+        assert_eq!(
+            exact(&[18], precondition_reason).unwrap(),
+            PreconditionFailureReason::MeasureOrderUnverifiable
+        );
+    }
+
     #[test]
     fn decoder_rejects_truncation_and_trailing_bytes() {
         let bytes = MaterializedState::default().canonical_bytes();

crates/epiphany-ops/src/effect.rs

@@ -185,6 +185,20 @@ pub enum PreconditionFailureReason {
     /// past its `i8` bound (Push 4a). The frozen `Transpose` saturates here
     /// and reports success; this refuses.
     TranspositionOutOfRange,
+    /// A `CreateMeasure` (or a prospective preservation check) found a
+    /// resolving `time_signature` that disagrees with the effective grid's
+    /// active signature (genesis tranche G3b, contract pin 8b) — distinct
+    /// from the resolution failure, which is `TargetMissing`.
+    MeasureMeterMismatch,
+    /// A `CreateMeasure`'s carried `start` is comparable to the current last
+    /// measure's start (contract pin 6) and is not strictly after it (genesis
+    /// tranche G3b, contract pin 8b).
+    MeasureOutOfOrder,
+    /// A `CreateMeasure` ordering or boundary-distance check could not be
+    /// verified: the two starts are not comparable (contract pin 6), or the
+    /// delta between them is not computable (contract pin 6b) (genesis
+    /// tranche G3b, contract pin 8b).
+    MeasureOrderUnverifiable,
 }
 
 impl PreconditionFailureReason {
@@ -210,6 +224,10 @@ impl PreconditionFailureReason {
             // Additive (Push 4a, TransposeInterval); appended past 13.
             PreconditionFailureReason::AcousticRealizationPinned => 14,
             PreconditionFailureReason::TranspositionOutOfRange => 15,
+            // Additive (Genesis tranche G3b); appended past 15.
+            PreconditionFailureReason::MeasureMeterMismatch => 16,
+            PreconditionFailureReason::MeasureOutOfOrder => 17,
+            PreconditionFailureReason::MeasureOrderUnverifiable => 18,
         }
     }
 }
@@ -243,6 +261,10 @@ impl PreconditionFailureReason {
             // Minor 7 (Push 4a).
             PreconditionFailureReason::AcousticRealizationPinned => Some(7),
             PreconditionFailureReason::TranspositionOutOfRange => Some(7),
+            // Minor 12 (Genesis tranche G3b).
+            PreconditionFailureReason::MeasureMeterMismatch => Some(12),
+            PreconditionFailureReason::MeasureOutOfOrder => Some(12),
+            PreconditionFailureReason::MeasureOrderUnverifiable => Some(12),
         }
     }
 }
@@ -512,6 +534,41 @@ mod tests {
         );
     }
 
+    /// (M5/M6/M7, M8/M9/M10) Genesis tranche G3b: the three new
+    /// `PreconditionFailureReason` variants sit at discriminants 16, 17, 18
+    /// (contract pin 8b), each at epoch `Some(12)`.
+    ///
+    /// **Mutation M5/M6/M7:** move any one discriminant to 19 (unused, so it
+    /// compiles); must fail. **Mutation M8/M9/M10:** move any one
+    /// `introduced_minor()` to `Some(11)`; must fail.
+    #[test]
+    fn genesis_g3b_reasons_are_16_17_18_at_epoch_12() {
+        assert_eq!(
+            PreconditionFailureReason::MeasureMeterMismatch.to_canonical_bytes(),
+            vec![16]
+        );
+        assert_eq!(
+            PreconditionFailureReason::MeasureOutOfOrder.to_canonical_bytes(),
+            vec![17]
+        );
+        assert_eq!(
+            PreconditionFailureReason::MeasureOrderUnverifiable.to_canonical_bytes(),
+            vec![18]
+        );
+        assert_eq!(
+            PreconditionFailureReason::MeasureMeterMismatch.introduced_minor(),
+            Some(12)
+        );
+        assert_eq!(
+            PreconditionFailureReason::MeasureOutOfOrder.introduced_minor(),
+            Some(12)
+        );
+        assert_eq!(
+            PreconditionFailureReason::MeasureOrderUnverifiable.introduced_minor(),
+            Some(12)
+        );
+    }
+
     #[test]
     fn voice_promotion_repair_round_trips_shape() {
         let r = RepairRecord {

crates/epiphany-ops/src/envdecode.rs

@@ -32,7 +32,7 @@
 use std::collections::BTreeSet;
 
 use epiphany_core::{
-    AnalysisLayer, CanvasLayoutDefaults, EventId, Instrument, InstrumentId, MetricGrid,
+    AnalysisLayer, CanvasLayoutDefaults, EventId, Instrument, InstrumentId, Measure, MetricGrid,
     MusicalPosition, OperationId, PartDefinition, PitchId, PitchSpelling, RegionId,
     RegionTimeModel, RepeatStructureId, ReplicaId, ScoreMetadata, SpellingPrecedence, Staff,
     StaffGroup, StaffInstance, StaffInstanceId, StaffLineConfiguration, TimeAnchor, TimeSignature,
@@ -612,6 +612,10 @@ fn operation_kind(r: &mut Reader<'_>) -> Result<OperationKind> {
         38 => OperationKind::CreateView(CreateViewOp {
             view: value::<ViewDefinition>(r, "ViewDefinition")?,
         }),
+        39 => OperationKind::CreateMeasure(CreateMeasureOp {
+            instance: staff_instance_id(r)?,
+            measure: value::<Measure>(r, "Measure")?,
+        }),
         tag => {
             return Err(EnvelopeDecodeError::InvalidTag {
                 kind: "OperationKind",
@@ -948,6 +952,16 @@ pub(crate) mod tests {
                     ),
                 })
             }
+            OperationKindTag::CreateMeasure => {
+                OperationKind::CreateMeasure(crate::payload::CreateMeasureOp {
+                    instance: si(),
+                    measure: valuegen::measure(
+                        epiphany_core::MeasureId::new(ReplicaId(7), 1),
+                        epiphany_core::TimeSignatureId::new(ReplicaId(7), 1),
+                        1,
+                    ),
+                })
+            }
         }
     }
 

crates/epiphany-ops/src/fuzz.rs

@@ -91,7 +91,7 @@ fn pitch(n: u64) -> PitchId {
 
 /// Generates a random payload over the shared id space.
 fn gen_payload(rng: &mut SplitMix64) -> OperationPayload {
-    let kind = match rng.below(36) {
+    let kind = match rng.below(37) {
         0 => {
             let voice = VoiceId::new(ReplicaId(7), rng.below(3));
             let position = MusicalPosition(RationalTime::from_int(rng.below(4) as i32));
@@ -329,6 +329,17 @@ fn gen_payload(rng: &mut SplitMix64) -> OperationPayload {
                 vec![AnalysisLayerId::new(ReplicaId(7), rng.below(2))],
             ),
         }),
+        // Genesis tranche G3b: append a measure onto the shared staff-instance
+        // id space, over the shared measure/time-signature id spaces so
+        // mints/re-carries genuinely interact with them.
+        36 => OperationKind::CreateMeasure(crate::payload::CreateMeasureOp {
+            instance: StaffInstanceId::new(ReplicaId(7), rng.below(3)),
+            measure: valuegen::measure(
+                epiphany_core::MeasureId::new(ReplicaId(7), rng.below(4)),
+                epiphany_core::TimeSignatureId::new(ReplicaId(7), rng.below(2)),
+                rng.below(4) as u32,
+            ),
+        }),
         _ => OperationKind::SetStaffLayout(SetStaffLayoutOp {
             staff_instance: StaffInstanceId::new(ReplicaId(7), rng.below(3)),
             instrument_override: None,

crates/epiphany-ops/src/lib.rs

@@ -125,17 +125,17 @@ pub use migrate::{migrate_v0_envelope, project_v1_to_v0, MigrationError};
 pub use opset::{AcceptOutcome, OperationSet};
 pub use payload::{
     operation_block_introduced_minor, ChangeRegionTimeModelOp, CreateAnalysisLayerOp,
-    CreateCrossCuttingOp, CreateInstrumentOp, CreatePartDefinitionOp, CreateRegionOp,
+    CreateCrossCuttingOp, CreateInstrumentOp, CreateMeasureOp, CreatePartDefinitionOp,
-    CreateRepeatStructureOp, CreateStaffGroupOp, CreateStaffInstanceOp, CreateStaffOp,
+    CreateRegionOp, CreateRepeatStructureOp, CreateStaffGroupOp, CreateStaffInstanceOp,
-    CreateViewOp, CreateVoiceOp, CrossCuttingValue, DeleteCrossCuttingOp, DeleteEventOp,
+    CreateStaffOp, CreateViewOp, CreateVoiceOp, CrossCuttingValue, DeleteCrossCuttingOp,
-    DeleteIdentifiedPitchOp, DeleteRegionOp, DeleteRepeatStructureOp, DeleteStaffInstanceOp,
+    DeleteEventOp, DeleteIdentifiedPitchOp, DeleteRegionOp, DeleteRepeatStructureOp,
-    DeleteVoiceOp, InsertEventOp, InsertIdentifiedPitchOp, ModifyCrossCuttingOp, ModifyEventOp,
+    DeleteStaffInstanceOp, DeleteVoiceOp, InsertEventOp, InsertIdentifiedPitchOp,
-    ModifyIdentifiedPitchOp, OperationKind, OperationKindTag, OperationPayload, PositionRemapping,
+    ModifyCrossCuttingOp, ModifyEventOp, ModifyIdentifiedPitchOp, OperationKind, OperationKindTag,
-    ResolveConflictPayload, ResolveEquivocationPayload, RespellPitchOp, SetCanvasLayoutDefaultsOp,
+    OperationPayload, PositionRemapping, ResolveConflictPayload, ResolveEquivocationPayload,
-    SetMetadataOp, SetMetricGridOp, SetSpellingPrecedenceOp, SetStaffLayoutOp, SetTempoSegmentOp,
+    RespellPitchOp, SetCanvasLayoutDefaultsOp, SetMetadataOp, SetMetricGridOp,
-    SetTimeSignatureOp, SetTuningContextOp, SetUserPageBreakOp, SetUserSystemBreakOp,
+    SetSpellingPrecedenceOp, SetStaffLayoutOp, SetTempoSegmentOp, SetTimeSignatureOp,
-    TransactionCategory, TransactionDescriptor, TransposeIntervalOp, TransposeOp,
+    SetTuningContextOp, SetUserPageBreakOp, SetUserSystemBreakOp, TransactionCategory,
-    TupletCompensation,
+    TransactionDescriptor, TransposeIntervalOp, TransposeOp, TupletCompensation,
 };
 pub use reduce::{
     canonical_reduction_order, GraphMaterialization, MaterializedState, ObjectState, PendingReason,

crates/epiphany-ops/src/migrate.rs

@@ -197,6 +197,8 @@ fn project_kind(kind: &OperationKind) -> V0OperationKind {
         }
         OperationKind::CreateAnalysisLayer(op) => V0OperationKind::CreateAnalysisLayer(op.clone()),
         OperationKind::CreateView(op) => V0OperationKind::CreateView(op.clone()),
+        // Genesis tranche G3b: born past v0; projected verbatim.
+        OperationKind::CreateMeasure(op) => V0OperationKind::CreateMeasure(op.clone()),
     }
 }
 
@@ -368,6 +370,8 @@ fn migrate_kind(kind: &V0OperationKind, context: &Score) -> Result<OperationKind
         }
         V0OperationKind::CreateAnalysisLayer(op) => OperationKind::CreateAnalysisLayer(op.clone()),
         V0OperationKind::CreateView(op) => OperationKind::CreateView(op.clone()),
+        // Genesis tranche G3b: identity round-trip (no lossy v0 form).
+        V0OperationKind::CreateMeasure(op) => OperationKind::CreateMeasure(op.clone()),
     })
 }
 

crates/epiphany-ops/src/payload.rs

@@ -33,13 +33,14 @@
 
 use epiphany_core::{
     AnalysisLayer, AnalysisLayerId, Beam, CanonicalValue, CanvasLayoutDefaults, Event,
-    EventDuration, EventId, EventPosition, IdentifiedPitch, Instrument, InstrumentId, MetricGrid,
+    EventDuration, EventId, EventPosition, IdentifiedPitch, Instrument, InstrumentId, Measure,
-    MusicalDuration, MusicalPosition, OperationId, PartDefinition, PartDefinitionId, Pitch,
+    MeasureId, MetricGrid, MusicalDuration, MusicalPosition, OperationId, PartDefinition,
-    PitchId, PitchSpelling, Region, RegionId, RegionTimeModel, RepeatStructure, RepeatStructureId,
+    PartDefinitionId, Pitch, PitchId, PitchSpelling, Region, RegionId, RegionTimeModel,
-    Rest, ScoreMetadata, Slur, Spanner, SpellingPrecedence, Staff, StaffGroup, StaffGroupId,
+    RepeatStructure, RepeatStructureId, Rest, ScoreMetadata, Slur, Spanner, SpellingPrecedence,
-    StaffId, StaffInstance, StaffInstanceId, StaffLineConfiguration, TempoSegment, Tie, TimeAnchor,
+    Staff, StaffGroup, StaffGroupId, StaffId, StaffInstance, StaffInstanceId,
-    TimeSignature, TransactionId, TranspositionInterval, TuningContextSettings, TupletId,
+    StaffLineConfiguration, TempoSegment, Tie, TimeAnchor, TimeSignature, TransactionId,
-    TypedObjectId, ViewDefinition, ViewId, Voice, VoiceId,
+    TranspositionInterval, TuningContextSettings, TupletId, TypedObjectId, ViewDefinition, ViewId,
+    Voice, VoiceId,
 };
 use epiphany_determinism::{
     sorted_canonical, CanonicalDecode, CanonicalEncode, CanonicalSet, DecodeError,
@@ -294,6 +295,15 @@ pub enum OperationKind {
     /// reduction preconditions every carried active layer resolves to a live
     /// `AnalysisLayer`.
     CreateView(CreateViewOp),
+    // --- Genesis tranche G3b (`spec/CONTRACT_GENESIS_G3B_MEASURE.md`): the
+    // final rung of the genesis ladder. Discriminant extends additively past
+    // 38. ---
+    /// Append a measure to a live staff instance (append-only set-union
+    /// creation, contract pin 4/9). Carries the owning instance id beside the
+    /// full `Measure` value, mirroring `CreateStaffInstance`: `Measure` has no
+    /// back-pointer to its parent, so the parent must ride along in the
+    /// payload (and in the reducer's carried-value map, contract pin 5).
+    CreateMeasure(CreateMeasureOp),
 }
 
 impl OperationKind {
@@ -415,6 +425,8 @@ impl OperationKind {
             OperationKind::CreatePartDefinition(_) => 36,
             OperationKind::CreateAnalysisLayer(_) => 37,
             OperationKind::CreateView(_) => 38,
+            // Genesis tranche G3b; appended past 38.
+            OperationKind::CreateMeasure(_) => 39,
         }
     }
 
@@ -481,6 +493,9 @@ impl OperationKind {
             | OperationKind::CreatePartDefinition(_)
             | OperationKind::CreateAnalysisLayer(_)
             | OperationKind::CreateView(_) => Some(11),
+            // Minor 12 (Genesis tranche G3b), ratified
+            // `spec/PLAN_GMINOR_SCHEMA_MINOR.md` §4.
+            OperationKind::CreateMeasure(_) => Some(12),
         }
     }
 
@@ -536,6 +551,9 @@ impl OperationKind {
             OperationKind::CreatePartDefinition(_) => OperationKindTag::CreatePartDefinition,
             OperationKind::CreateAnalysisLayer(_) => OperationKindTag::CreateAnalysisLayer,
             OperationKind::CreateView(_) => OperationKindTag::CreateView,
+            // Genesis tranche G3b. Name-verbatim, as every genesis addition
+            // since G1 has been (contract pin 3's precedent).
+            OperationKind::CreateMeasure(_) => OperationKindTag::CreateMeasure,
         }
     }
 }
@@ -586,6 +604,7 @@ impl CanonicalEncode for OperationKind {
             OperationKind::CreatePartDefinition(op) => op.encode_canonical(out),
             OperationKind::CreateAnalysisLayer(op) => op.encode_canonical(out),
             OperationKind::CreateView(op) => op.encode_canonical(out),
+            OperationKind::CreateMeasure(op) => op.encode_canonical(out),
         }
     }
 }
@@ -650,6 +669,8 @@ pub enum OperationKindTag {
     CreateAnalysisLayer,
     /// Genesis tranche G3a.
     CreateView,
+    /// Genesis tranche G3b.
+    CreateMeasure,
 }
 
 /// The discriminant of [`OperationKindTag::Registered`], the one tag that
@@ -769,6 +790,7 @@ operation_kind_tag_vocabulary! {
     CreatePartDefinition = 36 => "create-part-definition" @ Some(11),
     CreateAnalysisLayer = 37 => "create-analysis-layer" @ Some(11),
     CreateView = 38 => "create-view" @ Some(11),
+    CreateMeasure = 39 => "create-measure" @ Some(12),
 }
 
 impl CanonicalEncode for OperationKindTag {
@@ -1856,6 +1878,39 @@ impl CanonicalEncode for CreateViewOp {
     }
 }
 
+// --- Genesis tranche G3b (`spec/CONTRACT_GENESIS_G3B_MEASURE.md`): the final
+// rung of the genesis ladder. `Measure` is a nested container child of
+// `StaffInstance`, not a `Score`-root vector, so this rides
+// `CreateStaffInstance`'s parent-carrying shape (contract pin 4), not the
+// nine root-level mints' bare-value shape above. ---
+
+/// Append a `Measure` to a live `StaffInstance` (operation_catalog
+/// §CreateMeasure). Carries the owning instance id beside the full `Measure`
+/// value — `Measure` has no back-pointer to its parent (`graph.rs`), so the
+/// parent must ride along, exactly like `CreateStaffInstanceOp::region`.
+/// Append-only set-union creation (contract pin 9): the measure is pushed at
+/// the end of `instance.measures`, gated on ordering, meter agreement, and
+/// boundary-distance preconditions against the effective grid.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct CreateMeasureOp {
+    pub instance: StaffInstanceId,
+    pub measure: Measure,
+}
+
+impl CreateMeasureOp {
+    /// The appended measure's identifier.
+    pub fn measure_id(&self) -> MeasureId {
+        self.measure.id
+    }
+}
+
+impl CanonicalEncode for CreateMeasureOp {
+    fn encode_canonical(&self, out: &mut Vec<u8>) {
+        push_canon(out, &self.instance);
+        push_lp_bytes(out, &self.measure.canonical_bytes());
+    }
+}
+
 /// Set, replace, or (`None`) remove the single meter change at the anchor's
 /// resolved musical position in a region's default metric grid
 /// (operation_catalog §"Meter and Tempo Overwrites"). Carries the full
@@ -2765,4 +2820,128 @@ mod tests {
         let rev = CrossCuttingValue::Slur(crate::valuegen::slur(s, b, a));
         assert_ne!(fwd.to_canonical_bytes(), rev.to_canonical_bytes());
     }
+
+    // -----------------------------------------------------------------
+    // Genesis tranche G3b (`spec/CONTRACT_GENESIS_G3B_MEASURE.md`).
+    // -----------------------------------------------------------------
+
+    fn g3b_sample_measure() -> Measure {
+        crate::valuegen::measure(
+            MeasureId::new(ReplicaId(1), 1),
+            epiphany_core::TimeSignatureId::new(ReplicaId(1), 1),
+            1,
+        )
+    }
+
+    /// (M1/M2) `CreateMeasure`'s kind discriminant and tag discriminant are
+    /// both 39, in both discriminant spaces (contract pin 1).
+    ///
+    /// **Mutation M1:** move the kind discriminant to 40; must fail.
+    /// **Mutation M2:** move the tag discriminant to 40; must fail. (The two
+    /// spaces are asserted independently — a G-minor lesson from
+    /// `TransposeInterval`.)
+    #[test]
+    fn g3b_m1_m2_kind_and_tag_discriminant_are_39() {
+        let kind = OperationKind::CreateMeasure(CreateMeasureOp {
+            instance: StaffInstanceId::new(ReplicaId(1), 1),
+            measure: g3b_sample_measure(),
+        });
+        let mut bytes = Vec::new();
+        kind.encode_canonical(&mut bytes);
+        assert_eq!(bytes[0], 39, "the kind discriminant byte must lead");
+        assert_eq!(kind.tag(), OperationKindTag::CreateMeasure);
+        assert_eq!(OperationKindTag::CreateMeasure.discriminant(), 39);
+    }
+
+    /// (M3/M4) `CreateMeasure`'s epoch is `Some(12)` in BOTH the kind's own
+    /// `introduced_minor()` and the tag vocabulary's epoch.
+    ///
+    /// **Mutation M3:** change `OperationKind::introduced_minor()`'s
+    /// `CreateMeasure` arm to `Some(11)`; must fail.
+    /// **Mutation M4:** change the tag vocabulary's `@ Some(12)` to
+    /// `Some(11)`; must fail.
+    #[test]
+    fn g3b_m3_m4_epoch_is_12_in_both_spaces() {
+        let kind = OperationKind::CreateMeasure(CreateMeasureOp {
+            instance: StaffInstanceId::new(ReplicaId(1), 1),
+            measure: g3b_sample_measure(),
+        });
+        assert_eq!(kind.introduced_minor(), Some(12));
+        assert_eq!(OperationKindTag::CreateMeasure.introduced_minor(), Some(12));
+    }
+
+    /// (M11) `CreateMeasure` gains NO `schema_major()` arm (pin 2: `Measure`
+    /// is schema major 0, so `OperationEnvelopeBlock` stays at 3). A block
+    /// containing ONLY a `CreateMeasure` envelope stamps major 0 — the block
+    /// composition is load-bearing: a mixed block would stamp from another
+    /// kind and pass even with an errant arm present.
+    ///
+    /// **Mutation:** add `OperationKind::CreateMeasure(_) => 3` to
+    /// `schema_major()`; must fail.
+    #[test]
+    fn g3b_m11_create_measure_only_block_stamps_major_zero() {
+        let kind = OperationKind::CreateMeasure(CreateMeasureOp {
+            instance: StaffInstanceId::new(ReplicaId(1), 1),
+            measure: g3b_sample_measure(),
+        });
+        assert_eq!(
+            kind.schema_major(),
+            0,
+            "CreateMeasure falls through the catch-all _ => 0 arm"
+        );
+        let envelopes = [envelope(
+            1,
+            OperationPayload::Primitive(OperationKind::CreateMeasure(CreateMeasureOp {
+                instance: StaffInstanceId::new(ReplicaId(1), 1),
+                measure: g3b_sample_measure(),
+            })),
+        )];
+        let major = envelopes
+            .iter()
+            .map(|e| e.schema_major())
+            .max()
+            .expect("one envelope");
+        assert_eq!(
+            major, 0,
+            "a block carrying only CreateMeasure stamps major 0"
+        );
+    }
+
+    /// (M13) `CreateMeasureOp::encode_canonical` pushes the parent
+    /// `StaffInstanceId` THEN the value — mirroring `CreateStaffInstanceOp`
+    /// (contract pin 4). Frozen literal bytes, not a round-trip assertion:
+    /// swapping the two fields' encode order round-trips fine on its own
+    /// (each half decodes to the right type), so only a byte literal catches
+    /// the reorder.
+    ///
+    /// **Mutation:** swap the two `push_canon`/`push_lp_bytes` calls in
+    /// `CreateMeasureOp::encode_canonical`; must fail.
+    #[test]
+    fn g3b_m13_create_measure_op_encodes_parent_then_value() {
+        let op = CreateMeasureOp {
+            instance: StaffInstanceId::new(ReplicaId(1), 7),
+            measure: g3b_sample_measure(),
+        };
+        let mut bytes = Vec::new();
+        op.encode_canonical(&mut bytes);
+
+        // The instance id leads: its own canonical form (`push_canon`) is a
+        // fixed-width id encoding, and this exact prefix is what a
+        // parent/value swap would move.
+        let mut instance_bytes = Vec::new();
+        push_canon(&mut instance_bytes, &op.instance);
+        assert!(
+            bytes.starts_with(&instance_bytes),
+            "the parent StaffInstanceId must be the first bytes encoded"
+        );
+
+        let mut value_bytes = Vec::new();
+        push_lp_bytes(&mut value_bytes, &op.measure.canonical_bytes());
+        assert_eq!(
+            bytes.len(),
+            instance_bytes.len() + value_bytes.len(),
+            "the payload is exactly parent-bytes then value-bytes, nothing else"
+        );
+        assert_eq!(&bytes[instance_bytes.len()..], &value_bytes[..]);
+    }
 }

crates/epiphany-ops/src/textproj_kind.rs

@@ -9,15 +9,15 @@ use unicode_normalization::UnicodeNormalization;
 
 use crate::payload::{
     ChangeRegionTimeModelOp, CreateAnalysisLayerOp, CreateCrossCuttingOp, CreateInstrumentOp,
-    CreatePartDefinitionOp, CreateRegionOp, CreateRepeatStructureOp, CreateStaffGroupOp,
+    CreateMeasureOp, CreatePartDefinitionOp, CreateRegionOp, CreateRepeatStructureOp,
-    CreateStaffInstanceOp, CreateStaffOp, CreateViewOp, CreateVoiceOp, DeleteCrossCuttingOp,
+    CreateStaffGroupOp, CreateStaffInstanceOp, CreateStaffOp, CreateViewOp, CreateVoiceOp,
-    DeleteEventOp, DeleteIdentifiedPitchOp, DeleteRegionOp, DeleteRepeatStructureOp,
+    DeleteCrossCuttingOp, DeleteEventOp, DeleteIdentifiedPitchOp, DeleteRegionOp,
-    DeleteStaffInstanceOp, DeleteVoiceOp, InsertEventOp, InsertIdentifiedPitchOp,
+    DeleteRepeatStructureOp, DeleteStaffInstanceOp, DeleteVoiceOp, InsertEventOp,
-    ModifyCrossCuttingOp, ModifyEventOp, ModifyIdentifiedPitchOp, OperationKind, OperationKindTag,
+    InsertIdentifiedPitchOp, ModifyCrossCuttingOp, ModifyEventOp, ModifyIdentifiedPitchOp,
-    RespellPitchOp, SetCanvasLayoutDefaultsOp, SetMetadataOp, SetMetricGridOp,
+    OperationKind, OperationKindTag, RespellPitchOp, SetCanvasLayoutDefaultsOp, SetMetadataOp,
-    SetSpellingPrecedenceOp, SetStaffLayoutOp, SetTempoSegmentOp, SetTimeSignatureOp,
+    SetMetricGridOp, SetSpellingPrecedenceOp, SetStaffLayoutOp, SetTempoSegmentOp,
-    SetTuningContextOp, SetUserPageBreakOp, SetUserSystemBreakOp, TransactionDescriptor,
+    SetTimeSignatureOp, SetTuningContextOp, SetUserPageBreakOp, SetUserSystemBreakOp,
-    TransposeIntervalOp, TransposeOp,
+    TransactionDescriptor, TransposeIntervalOp, TransposeOp,
 };
 use crate::support::OperationKindRegistryId;
 
@@ -241,6 +241,10 @@ impl TextValue for OperationKind {
                 production(self.tag(), vec![op.layer.project()])
             }
             OperationKind::CreateView(op) => production(self.tag(), vec![op.view.project()]),
+            OperationKind::CreateMeasure(op) => production(
+                self.tag(),
+                vec![op.instance.project(), op.measure.project()],
+            ),
         }
     }
 
@@ -618,6 +622,15 @@ impl TextValue for OperationKind {
                     view: TextValue::parse(view)?,
                 })
             }
+            OperationKindTag::CreateMeasure => {
+                let [instance, measure] = fields(s, tag, 2)? else {
+                    unreachable!("the arity-2 check returned two fields")
+                };
+                OperationKind::CreateMeasure(CreateMeasureOp {
+                    instance: TextValue::parse(instance)?,
+                    measure: TextValue::parse(measure)?,
+                })
+            }
         })
     }
 }
@@ -671,7 +684,7 @@ mod tests {
     #[test]
     fn every_operation_kind_round_trips_with_canonical_text() {
         let tags: Vec<_> = all_tags().collect();
-        assert_eq!(tags.len(), 39, "the grammar has 39 kind productions");
+        assert_eq!(tags.len(), 40, "the grammar has 40 kind productions");
         for tag in tags {
             round_trip(&sample_kind(tag));
         }

crates/epiphany-ops/src/v0.rs

@@ -123,6 +123,10 @@ pub enum V0OperationKind {
     CreatePartDefinition(crate::payload::CreatePartDefinitionOp),
     CreateAnalysisLayer(crate::payload::CreateAnalysisLayerOp),
     CreateView(crate::payload::CreateViewOp),
+    // Genesis tranche G3b — born at wire-disc 39; no lossy v0 form (v0
+    // predates the catalog entirely), so it round-trips by identity like
+    // every other v1-native kind above.
+    CreateMeasure(crate::payload::CreateMeasureOp),
 }
 
 /// v0 `InsertEvent`: the event was a bare [`EventId`] plus the reduction-relevant

crates/epiphany-ops/src/valuegen.rs

@@ -17,14 +17,14 @@ use std::collections::BTreeMap;
 use epiphany_core::{
     AcousticPitch, AcousticRealization, AleatoricAnchoringDiscipline, AleatoricTimeModel,
     AnalysisLayerId, AnchorOffset, Beam, BeamId, CmnNominal, Event, EventId, EventOrderingDAG,
-    EventPosition, IdentifiedPitch, MetricTimeModel, MusicalDuration, MusicalPosition,
+    EventPosition, IdentifiedPitch, Measure, MeasureId, MeasureNumberVisibility, MetricTimeModel,
-    PartDefinitionId, Pitch, PitchId, PitchSpaceId, PitchSpacePosition, PitchSpelling,
+    MusicalDuration, MusicalPosition, PartDefinitionId, Pitch, PitchId, PitchSpaceId,
-    PitchedEvent, ProportionalTimeModel, Region, RegionContent, RegionEdge, RegionId,
+    PitchSpacePosition, PitchSpelling, PitchedEvent, ProportionalTimeModel, Region, RegionContent,
-    RegionTimeModel, RepeatKind, RepeatStructure, RepeatStructureId, Rest, ScalePosition, Slur,
+    RegionEdge, RegionId, RegionTimeModel, RepeatKind, RepeatStructure, RepeatStructureId, Rest,
-    SlurId, SpellingAttachment, SpellingDirective, SpellingScope, SpellingSource,
+    ScalePosition, Slur, SlurId, SpellingAttachment, SpellingDirective, SpellingScope,
-    StaffBasedContent, StaffExtent, StaffGroupId, StaffId, StaffInstance, StaffInstanceId,
+    SpellingSource, StaffBasedContent, StaffExtent, StaffGroupId, StaffId, StaffInstance,
-    StemConfiguration, Tie, TieClass, TieId, TimeAnchor, TimeExtent, ViewId, Voice, VoiceId,
+    StaffInstanceId, StemConfiguration, Tie, TieClass, TieId, TimeAnchor, TimeExtent,
-    VoiceOrigin, Volta, WallClockDuration, WallClockTime,
+    TimeSignatureId, ViewId, Voice, VoiceId, VoiceOrigin, Volta, WallClockDuration, WallClockTime,
 };
 
 /// A deterministic, fully-specified C4 pitch in the cmn-12 space — the neutral
@@ -424,6 +424,38 @@ pub fn view(id: ViewId, active_layers: Vec<AnalysisLayerId>) -> epiphany_core::V
     }
 }
 
+/// A minimal [`Measure`] (genesis tranche G3b) — the value a `CreateMeasure`
+/// appends: anchored to a `WallClock` point (deliberately, over an id-carrying
+/// shape — see below), with an explicit signature reference and number.
+///
+/// **Field-length distinguishability (contract §3's `valuegen` trap, from
+/// G3a's `analysis_layer` mistake — a name that happened to share its
+/// encoded byte width with the 16-byte `id` field made a field-swap mutation
+/// byte-invisible):** `Measure` has five fields; this fixture's chosen
+/// encodings are MUTUALLY DISTINCT in length — `id` (an identifier, a
+/// length-prefixed leaf: 4-byte length + 16-byte payload = 20 bytes),
+/// `start` (a `WallClock` anchor: 1-byte variant tag + a `WallClockTime` leaf,
+/// 4+8 = 12 bytes, so 13 total — deliberately not an `Event`/`Measure`/
+/// `Region` anchor, whose embedded id-leaf would collide with `id`'s own
+/// width), `time_signature` (`Some`: 1-byte tag + a 20-byte id-leaf = 21
+/// bytes), `explicit_number` (`Some`: 1-byte tag + a bare 4-byte `u32`, NOT
+/// leaf-framed = 5 bytes), and `number_visibility` (a C-style enum: 1 tag
+/// byte, no leaf framing) — 20, 13, 21, 5, 1 are pairwise distinct, so a
+/// `struct_codec!` field reorder (M12) changes the byte layout, not merely
+/// reinterprets it. Verified against `leaf_codec!`/`Option<T>`/`u32`'s actual
+/// `Codec` impls (`codec.rs`), not assumed.
+pub fn measure(id: MeasureId, time_signature: TimeSignatureId, explicit_number: u32) -> Measure {
+    Measure {
+        id,
+        start: TimeAnchor::WallClock {
+            time: WallClockTime(1_000_000_000 * i64::from(explicit_number)),
+        },
+        time_signature: Some(time_signature),
+        explicit_number: Some(explicit_number),
+        number_visibility: MeasureNumberVisibility::Auto,
+    }
+}
+
 /// Canvas layout defaults with an `nth`-distinct page width (genesis tranche
 /// G2a) — distinct `nth` give distinct `CanvasLayoutDefaults` values so a
 /// harness can drive concurrent `SetCanvasLayoutDefaults`s, an advisory LWW

crates/epiphany-ops/src/vectors.rs

@@ -564,6 +564,45 @@ pub fn decode_vectors() -> Vec<DecodeVector> {
         view_trailing,
     ));
 
+    // Genesis tranche G3b (kind 39, `spec/CONTRACT_GENESIS_G3B_MEASURE.md`).
+    let measure_envelope = OperationEnvelope {
+        id: OperationId::new(ReplicaId(1), 9),
+        author: crate::support::AuthorId(0),
+        stamp: crate::stamp::OperationStamp::new(
+            crate::stamp::HybridLogicalClock::new(epiphany_core::WallClockTime(1), 1),
+            OperationId::new(ReplicaId(1), 9),
+        ),
+        causal_context: crate::causal::CausalContext::new(),
+        transaction: None,
+        payload: crate::payload::OperationPayload::Primitive(
+            crate::payload::OperationKind::CreateMeasure(crate::payload::CreateMeasureOp {
+                instance: epiphany_core::StaffInstanceId::new(ReplicaId(1), 1),
+                measure: crate::valuegen::measure(
+                    epiphany_core::MeasureId::new(ReplicaId(1), 1),
+                    epiphany_core::TimeSignatureId::new(ReplicaId(1), 1),
+                    1,
+                ),
+            }),
+        ),
+    };
+    let measure_envelope_bytes = measure_envelope.to_canonical_bytes();
+    v.push(row(
+        OE,
+        "accept",
+        "-",
+        "create_measure",
+        measure_envelope_bytes.clone(),
+    ));
+    let mut measure_trailing = measure_envelope_bytes;
+    measure_trailing.push(0);
+    v.push(row(
+        OE,
+        "reject",
+        "trailing-bytes",
+        "create_measure_trailing",
+        measure_trailing,
+    ));
+
     v
 }
 

crates/epiphany-testkit/src/generators.rs

@@ -34,23 +34,23 @@ use epiphany_ops::{
     AnomalousReplicaSegment, AuthorId, CausalContext, ChangeRegionTimeModelOp, ConflictId,
     ConflictKind, ConflictKindRegistryId, ConflictRecord, ConflictRegistry,
     ConflictResolutionState, CreateAnalysisLayerOp, CreateCrossCuttingOp, CreateInstrumentOp,
-    CreatePartDefinitionOp, CreateRegionOp, CreateRepeatStructureOp, CreateStaffGroupOp,
+    CreateMeasureOp, CreatePartDefinitionOp, CreateRegionOp, CreateRepeatStructureOp,
-    CreateStaffInstanceOp, CreateStaffOp, CreateViewOp, CreateVoiceOp, CrossCuttingValue,
+    CreateStaffGroupOp, CreateStaffInstanceOp, CreateStaffOp, CreateViewOp, CreateVoiceOp,
-    DeleteCrossCuttingOp, DeleteEventOp, DeleteIdentifiedPitchOp, DeleteRegionOp,
+    CrossCuttingValue, DeleteCrossCuttingOp, DeleteEventOp, DeleteIdentifiedPitchOp,
-    DeleteRepeatStructureOp, DeleteStaffInstanceOp, DeleteVoiceOp, ExtensionPreconditionId,
+    DeleteRegionOp, DeleteRepeatStructureOp, DeleteStaffInstanceOp, DeleteVoiceOp,
-    FieldPath, HybridLogicalClock, InsertEventOp, InsertIdentifiedPitchOp, IntegrityAnomaly,
+    ExtensionPreconditionId, FieldPath, HybridLogicalClock, InsertEventOp, InsertIdentifiedPitchOp,
-    IntegrityAnomalyKind, IntegrityAnomalyRegistryId, MaterializedState, ModifyCrossCuttingOp,
+    IntegrityAnomaly, IntegrityAnomalyKind, IntegrityAnomalyRegistryId, MaterializedState,
-    ModifyEventOp, ModifyIdentifiedPitchOp, NoOpReason, ObjectKind, ObjectState, OperationEffect,
+    ModifyCrossCuttingOp, ModifyEventOp, ModifyIdentifiedPitchOp, NoOpReason, ObjectKind,
-    OperationEnvelope, OperationKind, OperationKindRegistryId, OperationPayload, OperationSet,
+    ObjectState, OperationEffect, OperationEnvelope, OperationKind, OperationKindRegistryId,
-    OperationStamp, PendingReason, PositionRemapping, PreconditionFailureReason,
+    OperationPayload, OperationSet, OperationStamp, PendingReason, PositionRemapping,
-    PreconditionFailureRegistryId, ReanchorReason, ReanchorReasonRegistryId, ReanchorResult,
+    PreconditionFailureReason, PreconditionFailureRegistryId, ReanchorReason,
-    RepairKind, RepairKindRegistryId, RepairRecord, ReplicaAnomalyReason, ReplicaAnomalyRegistryId,
+    ReanchorReasonRegistryId, ReanchorResult, RepairKind, RepairKindRegistryId, RepairRecord,
-    ResolutionAction, ResolutionRegistryId, ResolveConflictPayload, RespellPitchOp,
+    ReplicaAnomalyReason, ReplicaAnomalyRegistryId, ResolutionAction, ResolutionRegistryId,
-    SerializedCanonicalInputs, SetCanvasLayoutDefaultsOp, SetMetadataOp, SetMetricGridOp,
+    ResolveConflictPayload, RespellPitchOp, SerializedCanonicalInputs, SetCanvasLayoutDefaultsOp,
-    SetSpellingPrecedenceOp, SetStaffLayoutOp, SetTempoSegmentOp, SetTimeSignatureOp,
+    SetMetadataOp, SetMetricGridOp, SetSpellingPrecedenceOp, SetStaffLayoutOp, SetTempoSegmentOp,
-    SetTuningContextOp, SetUserPageBreakOp, SetUserSystemBreakOp, TransactionCategory,
+    SetTimeSignatureOp, SetTuningContextOp, SetUserPageBreakOp, SetUserSystemBreakOp,
-    TransactionDescriptor, TransposeIntervalOp, TransposeOp, TupletCompensation,
+    TransactionCategory, TransactionDescriptor, TransposeIntervalOp, TransposeOp,
-    TupletCompensationKind, UndoPolicy, UndoTransactionPayload,
+    TupletCompensation, TupletCompensationKind, UndoPolicy, UndoTransactionPayload,
 };
 
 use crate::rng::Rng;
@@ -414,7 +414,7 @@ pub fn conflict_registry(rng: &mut Rng) -> ConflictRegistry {
 
 /// A typed precondition failure (every core and registered variant).
 pub fn precondition_failure_reason(rng: &mut Rng) -> PreconditionFailureReason {
-    match rng.below(14) {
+    match rng.below(19) {
         0 => PreconditionFailureReason::TargetMissing,
         1 => PreconditionFailureReason::TargetTombstoned,
         2 => PreconditionFailureReason::WrongRegionTimeModel,
@@ -427,7 +427,15 @@ pub fn precondition_failure_reason(rng: &mut Rng) -> PreconditionFailureReason {
         9 => PreconditionFailureReason::TempoMapMalformed,
         10 => PreconditionFailureReason::SystemDerivedContentImmutable,
         11 => PreconditionFailureReason::RecreateContentMismatch,
-        12 => PreconditionFailureReason::ExtensionPrecondition(ExtensionPreconditionId(
+        // Push 4a (previously a decoder hole this generator never reached —
+        // P13-S20, closed by genesis tranche G3b's row 12a repair).
+        12 => PreconditionFailureReason::AcousticRealizationPinned,
+        13 => PreconditionFailureReason::TranspositionOutOfRange,
+        // Genesis tranche G3b.
+        14 => PreconditionFailureReason::MeasureMeterMismatch,
+        15 => PreconditionFailureReason::MeasureOutOfOrder,
+        16 => PreconditionFailureReason::MeasureOrderUnverifiable,
+        17 => PreconditionFailureReason::ExtensionPrecondition(ExtensionPreconditionId(
             rng.next_u64() as u128,
         )),
         _ => PreconditionFailureReason::Registered(PreconditionFailureRegistryId(
@@ -647,7 +655,7 @@ pub fn operation_payload(rng: &mut Rng, events: u64, pitches: u64) -> OperationP
         }
         _ => {}
     }
-    let kind = match rng.below(39) {
+    let kind = match rng.below(40) {
         0 => {
             let pitches = if rng.boolean() {
                 vec![obj_pitch(rng.below(pitches))]
@@ -899,6 +907,16 @@ pub fn operation_payload(rng: &mut Rng, events: u64, pitches: u64) -> OperationP
                 vec![AnalysisLayerId::new(OBJ_REPLICA, rng.below(2))],
             ),
         }),
+        // Genesis tranche G3b: append a measure onto the shared
+        // staff-instance id space.
+        38 => OperationKind::CreateMeasure(CreateMeasureOp {
+            instance: StaffInstanceId::new(OBJ_REPLICA, rng.below(2)),
+            measure: valuegen::measure(
+                MeasureId::new(OBJ_REPLICA, rng.below(2)),
+                TimeSignatureId::new(OBJ_REPLICA, rng.below(2)),
+                rng.below(4) as u32,
+            ),
+        }),
         _ => OperationKind::Registered(
             OperationKindRegistryId(rng.next_u64() as u128),
             rng.byte_vec(0, 16),
@@ -1929,7 +1947,7 @@ mod tests {
     /// Push-4a debt) and `CreateInstrument` (kind 31, G1 debt) went missing
     /// from every corpus this generator feeds despite every downstream suite
     /// staying green. Assert a bounded draw actually reaches every kind
-    /// appended past the historically-tested range (discriminants 30..=38),
+    /// appended past the historically-tested range (discriminants 30..=39),
     /// not just that the function does not panic.
     #[test]
     fn operation_payload_emits_every_appended_kind() {
@@ -1939,6 +1957,7 @@ mod tests {
         let mut saw_tuning_context = false;
         let (mut saw_create_staff_group, mut saw_create_part_definition) = (false, false);
         let (mut saw_create_analysis_layer, mut saw_create_view) = (false, false);
+        let mut saw_create_measure = false;
         for _ in 0..2000 {
             let OperationPayload::Primitive(kind) = operation_payload(&mut rng, 8, 8) else {
                 continue;
@@ -1953,6 +1972,7 @@ mod tests {
                 OperationKind::CreatePartDefinition(_) => saw_create_part_definition = true,
                 OperationKind::CreateAnalysisLayer(_) => saw_create_analysis_layer = true,
                 OperationKind::CreateView(_) => saw_create_view = true,
+                OperationKind::CreateMeasure(_) => saw_create_measure = true,
                 _ => {}
             }
         }
@@ -1992,6 +2012,54 @@ mod tests {
             saw_create_view,
             "CreateView (kind 38, G3a debt) never drawn in 2000 samples"
         );
+        assert!(
+            saw_create_measure,
+            "CreateMeasure (kind 39, G3b debt) never drawn in 2000 samples"
+        );
+    }
+
+    /// (M66, row 23) `precondition_failure_reason`'s doc comment claims
+    /// "every core and registered variant" — assert the bounded draw
+    /// actually reaches every one, including the genesis tranche G3b
+    /// additions (16–18) and the previously-untested Push 4a pair (14–15,
+    /// P13-S20).
+    ///
+    /// **Mutation:** revert `rng.below(19)` to `rng.below(14)`; must fail —
+    /// the generator would then never reach discriminants 14 through 18.
+    #[test]
+    fn precondition_failure_reason_reaches_every_variant() {
+        let mut rng = Rng::new(23);
+        let mut seen: std::collections::BTreeSet<u8> = std::collections::BTreeSet::new();
+        for _ in 0..2000 {
+            let reason = precondition_failure_reason(&mut rng);
+            let discriminant = match reason {
+                PreconditionFailureReason::TargetMissing => 0,
+                PreconditionFailureReason::TargetTombstoned => 1,
+                PreconditionFailureReason::WrongRegionTimeModel => 2,
+                PreconditionFailureReason::TupletCompensationInvalid => 3,
+                PreconditionFailureReason::EventDurationInvalid => 4,
+                PreconditionFailureReason::PositionOutsideRegion => 5,
+                PreconditionFailureReason::PitchSpaceMismatch => 6,
+                PreconditionFailureReason::VoiceMissing => 7,
+                PreconditionFailureReason::ContainerNotEmpty => 8,
+                PreconditionFailureReason::TempoMapMalformed => 9,
+                PreconditionFailureReason::SystemDerivedContentImmutable => 10,
+                PreconditionFailureReason::RecreateContentMismatch => 11,
+                PreconditionFailureReason::AcousticRealizationPinned => 12,
+                PreconditionFailureReason::TranspositionOutOfRange => 13,
+                PreconditionFailureReason::MeasureMeterMismatch => 14,
+                PreconditionFailureReason::MeasureOutOfOrder => 15,
+                PreconditionFailureReason::MeasureOrderUnverifiable => 16,
+                PreconditionFailureReason::ExtensionPrecondition(_) => 17,
+                PreconditionFailureReason::Registered(_) => 18,
+            };
+            seen.insert(discriminant);
+        }
+        let expected: std::collections::BTreeSet<u8> = (0..=18).collect();
+        assert_eq!(
+            seen, expected,
+            "the bounded draw must reach every core and registered variant"
+        );
     }
 
     #[test]

crates/epiphany-testkit/src/layout_stub.rs

@@ -1372,7 +1372,7 @@ mod tests {
 
     /// (s10, row 29) `gen_operation_kind_tag`'s draw must cover exactly
     /// `PAYLOAD_FREE` ∪ `{Registered}` — **not** merely the appended
-    /// discriminants 30..=38, which would pass even if the `Registered`
+    /// discriminants 30..=39, which would pass even if the `Registered`
     /// append (structurally different from every built-in: it is the one
     /// variant `PAYLOAD_FREE` excludes by design, `payload.rs:469`) were
     /// deleted from the generator entirely.

crates/epiphany-testkit/tests/text_projection_grammar.rs

@@ -306,15 +306,16 @@ fn the_kind_productions_are_the_operation_vocabulary() {
     // appends a tag must bump it (genesis G1 took it from 31 to 32 by adding
     // `CreateInstrument`; genesis G2a took it from 32 to 34 by adding
     // `SetCanvasLayoutDefaults` and `SetSpellingPrecedence`; genesis G2b took
-    // it from 34 to 35 by adding `SetTuningContext`; genesis G3a takes it
+    // it from 34 to 35 by adding `SetTuningContext`; genesis G3a took it
     // from 35 to 39 by adding `CreateStaffGroup`, `CreatePartDefinition`,
-    // `CreateAnalysisLayer`, and `CreateView`). It stays a literal on
+    // `CreateAnalysisLayer`, and `CreateView`; genesis G3b takes it from 39
-    // purpose: deriving it from `PAYLOAD_FREE.len()` would make the assertion
+    // to 40 by adding `CreateMeasure`). It stays a literal on purpose:
+    // deriving it from `PAYLOAD_FREE.len()` would make the assertion
     // vacuous, since that is the very list it exists to pin.
     assert_eq!(
         expected.len(),
-        39,
+        40,
-        "38 payload-free kinds plus `Registered`"
+        "39 payload-free kinds plus `Registered`"
     );
 
     let actual = alternatives("kind");

crates/epiphany-textproj/src/lib.rs

@@ -56,7 +56,7 @@ use epiphany_ops::OperationEnvelope;
 /// and `create-view` to the `kind` production — the same reasoning as every
 /// prior kind append: extending the grammar without moving this constant
 /// would leave two incompatible grammars both claiming `(0 11 0)`.
-pub const COMPANION_VERSION: (u32, u32, u32) = (0, 12, 0);
+pub const COMPANION_VERSION: (u32, u32, u32) = (0, 13, 0);
 
 /// A parsed canonical Text Projection document.
 ///

crates/epiphany-textproj/src/parse.rs

@@ -650,11 +650,12 @@ mod tests {
 
     // Bumped with `COMPANION_VERSION` (0.7.0 → 0.8.0, genesis G1; 0.8.0 →
     // 0.9.0, genesis G2a; 0.9.0 → 0.10.0, G-minor; 0.10.0 → 0.11.0, genesis
-    // G2b; 0.11.0 → 0.12.0, genesis G3a). Kept a literal because `projection`
+    // G2b; 0.11.0 → 0.12.0, genesis G3a; 0.12.0 → 0.13.0, genesis G3b). Kept
-    // takes `&[&str]` and a formatted String would ripple through every call
+    // a literal because `projection` takes `&[&str]` and a formatted String
-    // site; `the_test_header_tracks_the_implemented_version` below fails
+    // would ripple through every call site;
-    // loudly if the two ever drift.
+    // `the_test_header_tracks_the_implemented_version` below fails loudly if
-    const HEADER: &str = "(text-projection (0 12 0))";
+    // the two ever drift.
+    const HEADER: &str = "(text-projection (0 13 0))";
     const DOCUMENT: &str = "(document #x00000000000000000000000000000001 (schema 0 1))";
 
     /// A minimal but complete valid projection: just the two mandatory lines.

crates/epiphany-textproj/src/vectors.rs

@@ -22,13 +22,13 @@ use epiphany_bundle::{
     ReductionAlgorithmVersion, SchemaVersion, SemVer, SnapshotId,
 };
 use epiphany_core::{
-    AnalysisLayerId, OperationId, PartDefinitionId, RegionId, ReplicaId, StaffGroupId, StaffId,
+    AnalysisLayerId, MeasureId, OperationId, PartDefinitionId, RegionId, ReplicaId, StaffGroupId,
-    ViewId, WallClockTime,
+    StaffId, StaffInstanceId, TimeSignatureId, ViewId, WallClockTime,
 };
 use epiphany_ops::{
-    AuthorId, CausalContext, CreateAnalysisLayerOp, CreatePartDefinitionOp, CreateStaffGroupOp,
+    AuthorId, CausalContext, CreateAnalysisLayerOp, CreateMeasureOp, CreatePartDefinitionOp,
-    CreateViewOp, DeleteRegionOp, HybridLogicalClock, OperationEnvelope, OperationKind,
+    CreateStaffGroupOp, CreateViewOp, DeleteRegionOp, HybridLogicalClock, OperationEnvelope,
-    OperationPayload, OperationStamp, SetTuningContextOp,
+    OperationKind, OperationPayload, OperationStamp, SetTuningContextOp,
 };
 
 use crate::parse::parse_document;
@@ -258,6 +258,27 @@ fn view_envelope(counter: u64, physical_time: i64) -> OperationEnvelope {
     }
 }
 
+/// Genesis tranche G3b (kind 39, `spec/CONTRACT_GENESIS_G3B_MEASURE.md`).
+/// Same rationale as `staff_group_envelope` above.
+fn measure_envelope(counter: u64, physical_time: i64) -> OperationEnvelope {
+    let id = OperationId::new(ReplicaId(1), counter);
+    OperationEnvelope {
+        id,
+        author: AuthorId(0xAB),
+        stamp: OperationStamp::new(HybridLogicalClock::new(WallClockTime(physical_time), 0), id),
+        causal_context: CausalContext::new(),
+        transaction: None,
+        payload: OperationPayload::Primitive(OperationKind::CreateMeasure(CreateMeasureOp {
+            instance: StaffInstanceId::new(ReplicaId(1), 1),
+            measure: epiphany_ops::valuegen::measure(
+                MeasureId::new(ReplicaId(1), 1),
+                TimeSignatureId::new(ReplicaId(1), 1),
+                1,
+            ),
+        })),
+    }
+}
+
 fn profiles(custom: bool) -> Vec<ProfileDeclaration> {
     let mut profiles = vec![ProfileDeclaration::full()];
     if custom {
@@ -416,6 +437,19 @@ fn accept_documents() -> Vec<(&'static str, String)> {
         envelopes: vec![view_envelope(11, 1100)],
     };
 
+    // Genesis G3b: kind 39 in the committed corpus. Same manifest-version
+    // discipline as `staff_group` etc above.
+    let measure = TextDocument {
+        document_id: DocumentId([10; 16]),
+        manifest_schema_version: SchemaVersion::V0,
+        lineage_id: None,
+        profiles: profiles(false),
+        extensions: Vec::new(),
+        canonical_base: None,
+        blobs: Vec::new(),
+        envelopes: vec![measure_envelope(12, 1200)],
+    };
+
     vec![
         ("minimal", project_text_document(&minimal)),
         ("set_tuning_context", project_text_document(&tuning_context)),
@@ -438,6 +472,7 @@ fn accept_documents() -> Vec<(&'static str, String)> {
             project_text_document(&analysis_layer),
         ),
         ("create_view", project_text_document(&view)),
+        ("create_measure", project_text_document(&measure)),
     ]
 }
 
@@ -522,16 +557,16 @@ pub fn document_vectors() -> Vec<TextVector> {
         .collect();
 
     // The rejected version must be one this crate does NOT implement. Genesis
-    // tranche G3a moved `COMPANION_VERSION` to 0.12.0, which had been this
+    // tranche G3b moved `COMPANION_VERSION` to 0.13.0, which had been this
     // vector's "future" version — leaving it would have made the negative
     // vector assert that the *correct* header is rejected. It now names
-    // 0.11.0, the immediately superseded companion, which is the better test
+    // 0.12.0, the immediately superseded companion, which is the better test
     // anyway: rejecting the version right behind you is exactly the deferred
     // migrate-on-read posture (`req:textproj:header-version`).
     let wrong_version = replace_once(
         minimal,
+        "(text-projection (0 13 0))",
         "(text-projection (0 12 0))",
-        "(text-projection (0 11 0))",
     );
     vectors.push((
         SURFACE,
@@ -851,7 +886,7 @@ mod tests {
     #[test]
     fn the_reference_implementation_agrees_with_every_vector() {
         match verify(COMMITTED) {
-            Ok(count) => assert_eq!(count, 18, "the corpus has unexpectedly thinned"),
+            Ok(count) => assert_eq!(count, 19, "the corpus has unexpectedly thinned"),
             Err(failures) => panic!(
                 "{} disagreement(s):\n{}",
                 failures.len(),
@@ -890,23 +925,15 @@ mod tests {
         );
     }
 
-    /// (t11) Genesis tranche G3a: text projection round-trips all four new
+    /// (t11) Genesis tranche G3a: text projection round-trips all four
     /// kinds (`create-staff-group`, `create-part-definition`,
-    /// `create-analysis-layer`, `create-view`), and the companion version is
+    /// `create-analysis-layer`, `create-view`) it added.
-    /// **0.12.0**, with the negative vector rejecting **0.11.0**.
     ///
     /// **Mutation:** drop one parse arm (e.g.
     /// `OperationKindTag::CreateStaffGroup` from `OperationKind::parse` in
-    /// `textproj_kind.rs`); must fail. Separately, leave `COMPANION_VERSION`
+    /// `textproj_kind.rs`); must fail.
-    /// at `(0, 11, 0)`; the negative vector must fail.
     #[test]
-    fn t11_g3a_kinds_round_trip_and_companion_is_0_12_0_rejecting_0_11_0() {
+    fn t11_g3a_kinds_round_trip() {
-        assert_eq!(
-            crate::COMPANION_VERSION,
-            (0, 12, 0),
-            "the companion version must be 0.12.0"
-        );
-
         for name in [
             "create_staff_group",
             "create_part_definition",
@@ -927,9 +954,41 @@ mod tests {
                 "{name}: project(serialize(parse(T))) == T must hold"
             );
         }
+    }
+
+    /// (t12) Genesis tranche G3b: text projection round-trips the new
+    /// `create-measure` kind, and the companion version is **0.13.0**, with
+    /// the negative vector rejecting **0.12.0** (the immediately superseded
+    /// companion).
+    ///
+    /// **Mutation:** drop `OperationKindTag::CreateMeasure` from
+    /// `OperationKind::parse` in `textproj_kind.rs`; must fail. Separately,
+    /// leave `COMPANION_VERSION` at `(0, 12, 0)`; the negative vector must
+    /// fail.
+    #[test]
+    fn t12_g3b_kinds_round_trip_and_companion_is_0_13_0_rejecting_0_12_0() {
+        assert_eq!(
+            crate::COMPANION_VERSION,
+            (0, 13, 0),
+            "the companion version must be 0.13.0"
+        );
+
+        let name = "create_measure";
+        let text = accept_documents()
+            .into_iter()
+            .find(|(n, _)| *n == name)
+            .unwrap_or_else(|| panic!("accept document is absent: {name}"))
+            .1;
+        let document = parse_document(&text).unwrap_or_else(|e| panic!("{name} must parse: {e}"));
+        assert_eq!(document.envelopes.len(), 1, "{name} carries one envelope");
+        let reprojected = project_text_document(&document);
+        assert_eq!(
+            reprojected, text,
+            "{name}: project(serialize(parse(T))) == T must hold"
+        );
 
         // The negative vector must reject exactly the immediately superseded
-        // companion, 0.11.0.
+        // companion, 0.12.0.
         let rows = parse(COMMITTED).expect("the committed corpus parses");
         let superseded = rows
             .iter()
@@ -938,8 +997,8 @@ mod tests {
         assert_eq!(superseded.verdict, "reject");
         let text = String::from_utf8(superseded.text.clone()).expect("utf8");
         assert!(
-            text.contains("(text-projection (0 11 0))"),
+            text.contains("(text-projection (0 12 0))"),
-            "the negative vector must name the immediately superseded companion 0.11.0, got: {text}"
+            "the negative vector must name the immediately superseded companion 0.12.0, got: {text}"
         );
         assert!(
             parse_document(&text).is_err(),

spec/text_projection.tex

@@ -234,7 +234,7 @@
   {\Large\scshape\color{epiphanyslate}Text Projection}\\[6pt]
   {\large\itshape\color{epiphanyslate}A companion to the Core Specification}\\[14pt]
   {\color{epiphanygold}\rule{3in}{0.8pt}}\\[24pt]
-  {\normalsize\color{epiphanyink}Version 0.12.0 --- The four remaining genesis root-level entity mints reach the grammar}\\[4pt]
+  {\normalsize\color{epiphanyink}Version 0.13.0 --- The genesis ladder closes: \texttt{create-measure} reaches the grammar}\\[4pt]
   {\small\color{epiphanyslate}Normative for the text form it defines}
   \vfill
 \end{titlepage}
@@ -483,7 +483,7 @@ A projection is, in order:
 \begin{requirement}
   \label{req:textproj:header-version}
   A parser implementing this companion \MUST{} accept exactly one header
-  version: \texttt{(0 12 0)}, the version of the companion it implements. It
+  version: \texttt{(0 13 0)}, the version of the companion it implements. It
   \MUST{} reject any other version at line one.
 
   Multi-version acceptance and text migrate-on-read are deferred in the same
@@ -534,7 +534,7 @@ projection introduces no ordering of its own.
   A parser \MUST{} reject every \texttt{(blob ...)} line whose blob is
   unreferenced by canonical state
   (Requirement~\ref{req:textproj:canonical-blobs}). At companion
-  version~0.12.0, neither a canonical operation nor canonical reduced state can
+  version~0.13.0, neither a canonical operation nor canonical reduced state can
   carry a \texttt{BlobId}; canonical state therefore cannot reference a blob,
   and a parser \MUST{} reject every \texttt{(blob ...)} line.
 \end{requirement}
@@ -1066,6 +1066,7 @@ kind           ::= "(insert-event " bytes " " value ")"
                | "(create-part-definition " value ")"
                | "(create-analysis-layer " value ")"
                | "(create-view " value ")"
+               | "(create-measure " value ")"
 
 tuplet-comp    ::= "not-in-tuplet" | "(replace-with-rest " value ")"
                | "(rewrite-tuplets (" bytes* "))"
@@ -1142,7 +1143,7 @@ A document of one operation --- a transposition of two pitches up a perfect
 fifth, over a compacted base --- projects to five lines:
 
 \begin{lstlisting}
-(text-projection (0 12 0))
+(text-projection (0 13 0))
 (document #x05050505050505050505050505050505 (schema 0 1))
 (profile full (0 1 0) (constraints 67108864 (retention 1 () true)))
 (canonical-base #x1f8b0000000000000000000000000000 #x 1 full (schema 0 1) #x0000)

spec/vectors/decode_vectors.txt

@@ -76,8 +76,9 @@ ops.operation_kind_tag accept - tag_35 23
 ops.operation_kind_tag accept - tag_36 24
 ops.operation_kind_tag accept - tag_37 25
 ops.operation_kind_tag accept - tag_38 26
+ops.operation_kind_tag accept - tag_39 27
 ops.operation_kind_tag accept - registered 1000000000000000000123456789abcdef
-ops.operation_kind_tag reject unknown-discriminant tag_39_one_past_the_vocabulary 27
+ops.operation_kind_tag reject unknown-discriminant tag_40_one_past_the_vocabulary 28
 ops.operation_kind_tag reject unknown-discriminant tag_200 c8
 ops.operation_kind_tag reject truncated tag_empty -
 ops.operation_kind_tag reject trailing-bytes insert_event_trailing 0000
@@ -100,6 +101,8 @@ ops.operation_envelope accept - create_analysis_layer 00000000000000010000000000
 ops.operation_envelope reject trailing-bytes create_analysis_layer_trailing 00000000000000010000000000000007000000000000000000000000000000000100000000000000010000000000000000000001000000000000000700000000000000000000251f0000001000000000000000000000010000000000000001070000006c617965722d3100
 ops.operation_envelope accept - create_view 000000000000000100000000000000080000000000000000000000000000000001000000000000000100000000000000000000010000000000000008000000000000000000002636000000100000000000000000000001000000000000000106000000766965772d31010000001000000000000000000000010000000000000001
 ops.operation_envelope reject trailing-bytes create_view_trailing 000000000000000100000000000000080000000000000000000000000000000001000000000000000100000000000000000000010000000000000008000000000000000000002636000000100000000000000000000001000000000000000106000000766965772d3101000000100000000000000000000001000000000000000100
+ops.operation_envelope accept - create_measure 0000000000000001000000000000000900000000000000000000000000000000010000000000000001000000000000000000000100000000000000090000000000000000000027000000000000000100000000000000013c0000001000000000000000000000010000000000000001030800000000ca9a3b00000000011000000000000000000000010000000000000001010100000000
+ops.operation_envelope reject trailing-bytes create_measure_trailing 0000000000000001000000000000000900000000000000000000000000000000010000000000000001000000000000000000000100000000000000090000000000000000000027000000000000000100000000000000013c0000001000000000000000000000010000000000000001030800000000ca9a3b0000000001100000000000000000000001000000000000000101010000000000
 
 # bundle.manifest
 bundle.manifest accept - empty_manifest 6f9e7d11689ab113c4a1f05faf60fe60050505050505050505050505050505050000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000001000000000000000000000400000000010000000001000000000000

spec/vectors/textproj_document_vectors.txt

@@ -22,21 +22,22 @@
 # document bytes are normative. `<utf8-hex>` is lowercase with no separators.
 
 # textproj.document
-textproj.document accept - minimal 28746578742d70726f6a656374696f6e202830203132203029290a28646f63756d656e7420237830313031303130313031303130313031303130313031303130313031303130312028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a
+textproj.document accept - minimal 28746578742d70726f6a656374696f6e202830203133203029290a28646f63756d656e7420237830313031303130313031303130313031303130313031303130313031303130312028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a
-textproj.document accept - set_tuning_context 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-textproj.document accept - create_staff_group 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
+textproj.document accept - create_staff_group 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
-textproj.document accept - create_part_definition 28746578742d70726f6a656374696f6e202830203132203029290a28646f63756d656e7420237830373037303730373037303730373037303730373037303730373037303730372028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a28656e76656c6f70652023783030303030303030303030303030303130303030303030303030303030303039202378303030303030303030303030303030303030303030303030303030303030616220287374616d70203930302030202378303030303030303030303030303030313030303030303030303030303030303929202863617573616c2028292028292920282920287072696d697469766520286372656174652d706172742d646566696e6974696f6e2028706172742d646566696e6974696f6e20237830303030303030303030303030303031303030303030303030303030303030312022706172742d312220282378303030303030303030303030303030313030303030303030303030303030303129292929290a
+textproj.document accept - create_part_definition 28746578742d70726f6a656374696f6e202830203133203029290a28646f63756d656e7420237830373037303730373037303730373037303730373037303730373037303730372028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a28656e76656c6f70652023783030303030303030303030303030303130303030303030303030303030303039202378303030303030303030303030303030303030303030303030303030303030616220287374616d70203930302030202378303030303030303030303030303030313030303030303030303030303030303929202863617573616c2028292028292920282920287072696d697469766520286372656174652d706172742d646566696e6974696f6e2028706172742d646566696e6974696f6e20237830303030303030303030303030303031303030303030303030303030303030312022706172742d312220282378303030303030303030303030303030313030303030303030303030303030303129292929290a
-textproj.document accept - create_analysis_layer 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
+textproj.document accept - create_analysis_layer 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
-textproj.document accept - create_view 28746578742d70726f6a656374696f6e202830203132203029290a28646f63756d656e7420237830393039303930393039303930393039303930393039303930393039303930392028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a28656e76656c6f70652023783030303030303030303030303030303130303030303030303030303030303062202378303030303030303030303030303030303030303030303030303030303030616220287374616d7020313130302030202378303030303030303030303030303030313030303030303030303030303030306229202863617573616c2028292028292920282920287072696d697469766520286372656174652d766965772028766965772d646566696e6974696f6e20237830303030303030303030303030303031303030303030303030303030303030312022766965772d312220282378303030303030303030303030303030313030303030303030303030303030303129292929290a
+textproj.document accept - create_view 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
-textproj.document reject wrong-header-version superseded_companion_version 28746578742d70726f6a656374696f6e202830203131203029290a28646f63756d656e7420237830313031303130313031303130313031303130313031303130313031303130312028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a
+textproj.document accept - create_measure 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
-textproj.document reject blob-line unreferenced_blob 28746578742d70726f6a656374696f6e202830203132203029290a28646f63756d656e7420237830313031303130313031303130313031303130313031303130313031303130312028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a28626c6f6220226170706c69636174696f6e2f6f637465742d73747265616d222028292023783031290a
+textproj.document reject wrong-header-version superseded_companion_version 28746578742d70726f6a656374696f6e202830203132203029290a28646f63756d656e7420237830313031303130313031303130313031303130313031303130313031303130312028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a
-textproj.document reject out-of-order-sections canonical_base_before_extension 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
+textproj.document reject blob-line unreferenced_blob 28746578742d70726f6a656374696f6e202830203133203029290a28646f63756d656e7420237830313031303130313031303130313031303130313031303130313031303130312028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e203120282920747275652929290a28626c6f6220226170706c69636174696f6e2f6f637465742d73747265616d222028292023783031290a
-textproj.document reject repeated-singular-section lineage_repeated 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
+textproj.document reject out-of-order-sections canonical_base_before_extension 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
-textproj.document reject operation-envelope-order envelopes_reversed 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
+textproj.document reject repeated-singular-section lineage_repeated 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
-textproj.document reject profile-declaration-order profiles_reversed 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
+textproj.document reject operation-envelope-order envelopes_reversed 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
-textproj.document reject extension-declaration-order extensions_reversed 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
+textproj.document reject profile-declaration-order profiles_reversed 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
-textproj.document reject extension-chunk-order extension_chunks_reversed 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
+textproj.document reject extension-declaration-order extensions_reversed 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
-textproj.document reject missing-trailing-lf final_lf_missing 28746578742d70726f6a656374696f6e202830203132203029290a28646f63756d656e7420237830313031303130313031303130313031303130313031303130313031303130312028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e20312028292074727565292929
+textproj.document reject extension-chunk-order extension_chunks_reversed 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
+textproj.document reject missing-trailing-lf final_lf_missing 28746578742d70726f6a656374696f6e202830203133203029290a28646f63756d656e7420237830313031303130313031303130313031303130313031303130313031303130312028736368656d612030203129290a2870726f66696c652066756c6c20283020312030292028636f6e73747261696e74732036373130383836342028726574656e74696f6e20312028292074727565292929