diff --git a/Cargo.toml b/Cargo.toml
index c94766b..a81d91d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,12 +1,12 @@
 # file: Cargo.toml
-# version: 642
+# version: 644
 
 [workspace]
 resolver = "3"
 members = ["crates/ksp-app-backfill-desk", "crates/ksp-app-config-desk", "crates/ksp-app-raw-transaction-ingest-desk", "crates/ksp-app-solprices-desk", "crates/ksp-app-store-desk", "crates/ksp-app-wallet-desk", "crates/ksp-config-lib", "crates/ksp-core-lib", "crates/ksp-interface-lib", "crates/ksp-job-api", "crates/ksp-job-backfill-lib", "crates/ksp-logging-lib", "crates/ksp-offchain-transport-lib", "crates/ksp-onchain-transport-lib", "crates/ksp-program-api", "crates/ksp-raw-transaction-lib", "crates/ksp-store-api", "crates/ksp-store-lib", "crates/ksp-store-postgres-lib", "crates/ksp-wallet-lib", "crates/ksp-worker-api", "crates/ksp-worker-raw-transaction-ingest-lib"]
 
 [workspace.package]
-version = "0.3.16-pre.4"
+version = "0.3.16-pre.5.fix.1"
 edition = "2024"
 license = "MIT"
 repository = "https://git.sasedev.com/Sasedev/khadhroony-solana-project"
diff --git a/crates/ksp-store-api/src/lib.rs b/crates/ksp-store-api/src/lib.rs
index 5ba08b8..5b6e415 100644
--- a/crates/ksp-store-api/src/lib.rs
+++ b/crates/ksp-store-api/src/lib.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-api/src/lib.rs
-// version: 8
+// version: 9
 #![warn(missing_docs)]
 #![deny(unreachable_pub)]
 #![forbid(unsafe_code)]
@@ -170,6 +170,8 @@ pub use self::model::raw_transaction::RawTransactionVariantReference;
 pub use self::model::raw_transaction::RawTransactionVariantRelation;
 /// Stable backend-neutral reason explaining one RAW transaction variant relation.
 pub use self::model::raw_transaction::RawTransactionVariantRelationReason;
+/// Compares one incoming RAW transaction variant against the currently canonical variant.
+pub use self::model::raw_transaction::compare_raw_transaction_variants;
 /// Common KSP error type used by Store-facing contracts.
 pub use ksp_core_lib::Error;
 /// Stable structured code identifying a KSP error category and condition.
diff --git a/crates/ksp-store-api/src/model/raw_transaction.rs b/crates/ksp-store-api/src/model/raw_transaction.rs
index ddb28f7..e65f0c0 100644
--- a/crates/ksp-store-api/src/model/raw_transaction.rs
+++ b/crates/ksp-store-api/src/model/raw_transaction.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-api/src/model/raw_transaction.rs
-// version: 3
+// version: 5
 
 /// Durable backend-independent identity of one canonical RAW transaction.
 #[derive(Clone, Debug, Eq, Hash, PartialEq)]
@@ -203,6 +203,51 @@ impl RawTransactionVariantComparison {
     }
 }
 
+/// Compares one incoming RAW transaction variant against the currently canonical variant.
+///
+/// The comparator is pure and backend-neutral. Automatic dominance is intentionally limited to
+/// a strictly proved `logMessages` truncation relation. Every other payload divergence fails closed
+/// as either [`RawTransactionVariantRelation::Conflict`] or [`RawTransactionVariantRelation::Incomparable`].
+pub fn compare_raw_transaction_variants(
+    canonical: &crate::RawTransaction,
+    incoming: &crate::RawTransaction,
+) -> crate::Result<crate::RawTransactionVariantComparison> {
+    if canonical.reference() != incoming.reference() {
+        return std::result::Result::Err(raw_variant_model_error("comparison.reference"));
+    }
+    if canonical.slot() != incoming.slot() {
+        return crate::RawTransactionVariantComparison::try_new(
+            crate::RawTransactionVariantRelation::Conflict,
+            crate::RawTransactionVariantRelationReason::SlotMismatch,
+        );
+    }
+    if canonical.block_time() != incoming.block_time() {
+        return crate::RawTransactionVariantComparison::try_new(
+            crate::RawTransactionVariantRelation::Conflict,
+            crate::RawTransactionVariantRelationReason::BlockTimeMismatch,
+        );
+    }
+    if canonical.payload().format_id() != incoming.payload().format_id() || canonical.payload().format_version() != incoming.payload().format_version() {
+        return crate::RawTransactionVariantComparison::try_new(
+            crate::RawTransactionVariantRelation::Incomparable,
+            crate::RawTransactionVariantRelationReason::PayloadFormatMismatch,
+        );
+    }
+    if canonical.payload().bytes() == incoming.payload().bytes() {
+        return crate::RawTransactionVariantComparison::try_new(
+            crate::RawTransactionVariantRelation::Exact,
+            crate::RawTransactionVariantRelationReason::ExactCanonicalContent,
+        );
+    }
+    if canonical.payload().content_hash() == incoming.payload().content_hash() {
+        return crate::RawTransactionVariantComparison::try_new(
+            crate::RawTransactionVariantRelation::Conflict,
+            crate::RawTransactionVariantRelationReason::ContentHashCollision,
+        );
+    }
+    return compare_raw_variant_payloads(canonical.payload().bytes(), incoming.payload().bytes());
+}
+
 /// Durable lifecycle status of one RAW transaction conflict case.
 #[non_exhaustive]
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
@@ -304,6 +349,384 @@ impl RawTransactionObservation {
     }
 }
 
+const MAX_RAW_VARIANT_JSON_DEPTH: usize = 128;
+const RAW_LOG_MESSAGES_KEY: &[u8] = b"\"logMessages\"";
+const RAW_META_KEY: &[u8] = b"\"meta\"";
+const RAW_TRUNCATION_MARKER_JSON: &[u8] = b"\"Log truncated\"";
+
+#[derive(Clone, Copy)]
+struct RawVariantJsonMember<'a> {
+    key: &'a [u8],
+    value: &'a [u8],
+}
+
+fn compare_raw_variant_payloads(canonical: &[u8], incoming: &[u8]) -> crate::Result<crate::RawTransactionVariantComparison> {
+    let canonical_members = raw_variant_json_object_members(canonical);
+    let incoming_members = raw_variant_json_object_members(incoming);
+    let (canonical_members, incoming_members) = match (canonical_members, incoming_members) {
+        (std::option::Option::Some(canonical_members), std::option::Option::Some(incoming_members)) => (canonical_members, incoming_members),
+        _ => return raw_variant_incomparable(),
+    };
+    if canonical_members.len() != incoming_members.len() {
+        return raw_variant_incomparable();
+    }
+    let mut canonical_meta = std::option::Option::None;
+    let mut incoming_meta = std::option::Option::None;
+    for (canonical_member, incoming_member) in canonical_members.iter().zip(incoming_members.iter()) {
+        if canonical_member.key != incoming_member.key {
+            return raw_variant_incomparable();
+        }
+        if canonical_member.key == RAW_META_KEY {
+            canonical_meta = std::option::Option::Some(canonical_member.value);
+            incoming_meta = std::option::Option::Some(incoming_member.value);
+            continue;
+        }
+        if canonical_member.value != incoming_member.value {
+            return raw_variant_concrete_difference(canonical_member.value, incoming_member.value);
+        }
+    }
+    let (canonical_meta, incoming_meta) = match (canonical_meta, incoming_meta) {
+        (std::option::Option::Some(canonical_meta), std::option::Option::Some(incoming_meta)) => (canonical_meta, incoming_meta),
+        _ => return raw_variant_incomparable(),
+    };
+    return compare_raw_variant_meta(canonical_meta, incoming_meta);
+}
+
+fn compare_raw_variant_meta(canonical: &[u8], incoming: &[u8]) -> crate::Result<crate::RawTransactionVariantComparison> {
+    if canonical == incoming {
+        return raw_variant_incomparable();
+    }
+    if canonical == b"null" || incoming == b"null" {
+        return raw_variant_incomparable();
+    }
+    let canonical_members = raw_variant_json_object_members(canonical);
+    let incoming_members = raw_variant_json_object_members(incoming);
+    let (canonical_members, incoming_members) = match (canonical_members, incoming_members) {
+        (std::option::Option::Some(canonical_members), std::option::Option::Some(incoming_members)) => (canonical_members, incoming_members),
+        _ => return raw_variant_concrete_difference(canonical, incoming),
+    };
+    if canonical_members.len() != incoming_members.len() {
+        return raw_variant_incomparable();
+    }
+    let mut canonical_logs = std::option::Option::None;
+    let mut incoming_logs = std::option::Option::None;
+    for (canonical_member, incoming_member) in canonical_members.iter().zip(incoming_members.iter()) {
+        if canonical_member.key != incoming_member.key {
+            return raw_variant_incomparable();
+        }
+        if canonical_member.key == RAW_LOG_MESSAGES_KEY {
+            canonical_logs = std::option::Option::Some(canonical_member.value);
+            incoming_logs = std::option::Option::Some(incoming_member.value);
+            continue;
+        }
+        if canonical_member.value != incoming_member.value {
+            return raw_variant_concrete_difference(canonical_member.value, incoming_member.value);
+        }
+    }
+    let (canonical_logs, incoming_logs) = match (canonical_logs, incoming_logs) {
+        (std::option::Option::Some(canonical_logs), std::option::Option::Some(incoming_logs)) => (canonical_logs, incoming_logs),
+        _ => return raw_variant_incomparable(),
+    };
+    if canonical_logs == incoming_logs {
+        return raw_variant_incomparable();
+    }
+    let canonical_items = raw_variant_json_array_items(canonical_logs);
+    let incoming_items = raw_variant_json_array_items(incoming_logs);
+    let (canonical_items, incoming_items) = match (canonical_items, incoming_items) {
+        (std::option::Option::Some(canonical_items), std::option::Option::Some(incoming_items)) => (canonical_items, incoming_items),
+        _ => return raw_variant_concrete_difference(canonical_logs, incoming_logs),
+    };
+    if raw_variant_log_messages_truncated(incoming_items.as_slice(), canonical_items.as_slice()) {
+        return crate::RawTransactionVariantComparison::try_new(
+            crate::RawTransactionVariantRelation::CompatibleLessComplete,
+            crate::RawTransactionVariantRelationReason::IncomingLogMessagesTruncated,
+        );
+    }
+    if raw_variant_log_messages_truncated(canonical_items.as_slice(), incoming_items.as_slice()) {
+        return crate::RawTransactionVariantComparison::try_new(
+            crate::RawTransactionVariantRelation::CompatibleMoreComplete,
+            crate::RawTransactionVariantRelationReason::CanonicalLogMessagesTruncated,
+        );
+    }
+    return raw_variant_concrete_difference(canonical_logs, incoming_logs);
+}
+
+fn raw_variant_concrete_difference(canonical: &[u8], incoming: &[u8]) -> crate::Result<crate::RawTransactionVariantComparison> {
+    if canonical == b"null" || incoming == b"null" {
+        return raw_variant_incomparable();
+    }
+    return crate::RawTransactionVariantComparison::try_new(
+        crate::RawTransactionVariantRelation::Conflict,
+        crate::RawTransactionVariantRelationReason::CanonicalPayloadConflict,
+    );
+}
+
+fn raw_variant_incomparable() -> crate::Result<crate::RawTransactionVariantComparison> {
+    return crate::RawTransactionVariantComparison::try_new(
+        crate::RawTransactionVariantRelation::Incomparable,
+        crate::RawTransactionVariantRelationReason::UnsupportedCanonicalDifference,
+    );
+}
+
+fn raw_variant_log_messages_truncated(truncated: &[&[u8]], full: &[&[u8]]) -> bool {
+    if truncated.is_empty() || full.is_empty() {
+        return false;
+    }
+    if !truncated.iter().all(|value| return raw_variant_json_is_string(value)) || !full.iter().all(|value| return raw_variant_json_is_string(value)) {
+        return false;
+    }
+    let marker_count = truncated.iter().filter(|value| return **value == RAW_TRUNCATION_MARKER_JSON).count();
+    if marker_count != 1 || truncated.last().copied() != std::option::Option::Some(RAW_TRUNCATION_MARKER_JSON) {
+        return false;
+    }
+    if full.iter().any(|value| return *value == RAW_TRUNCATION_MARKER_JSON) {
+        return false;
+    }
+    let prefix_len = truncated.len() - 1;
+    if prefix_len >= full.len() {
+        return false;
+    }
+    return truncated[..prefix_len] == full[..prefix_len];
+}
+
+fn raw_variant_json_object_members(value: &[u8]) -> std::option::Option<std::vec::Vec<RawVariantJsonMember<'_>>> {
+    if std::str::from_utf8(value).is_err() {
+        return std::option::Option::None;
+    }
+    let start = raw_variant_json_skip_whitespace(value, 0);
+    if value.get(start) != std::option::Option::Some(&b'{') {
+        return std::option::Option::None;
+    }
+    let end = match raw_variant_json_value_end(value, start, 0) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return std::option::Option::None,
+    };
+    if raw_variant_json_skip_whitespace(value, end) != value.len() {
+        return std::option::Option::None;
+    }
+    let mut index = raw_variant_json_skip_whitespace(value, start + 1);
+    let mut members = std::vec::Vec::new();
+    if value.get(index) == std::option::Option::Some(&b'}') {
+        return std::option::Option::Some(members);
+    }
+    loop {
+        let key_start = index;
+        let key_end = match raw_variant_json_string_end(value, key_start) {
+            std::option::Option::Some(value) => value,
+            std::option::Option::None => return std::option::Option::None,
+        };
+        index = raw_variant_json_skip_whitespace(value, key_end);
+        if value.get(index) != std::option::Option::Some(&b':') {
+            return std::option::Option::None;
+        }
+        index = raw_variant_json_skip_whitespace(value, index + 1);
+        let value_start = index;
+        let value_end = match raw_variant_json_value_end(value, value_start, 1) {
+            std::option::Option::Some(value) => value,
+            std::option::Option::None => return std::option::Option::None,
+        };
+        members.push(RawVariantJsonMember { key: &value[key_start..key_end], value: &value[value_start..value_end] });
+        index = raw_variant_json_skip_whitespace(value, value_end);
+        match value.get(index).copied() {
+            std::option::Option::Some(b',') => index = raw_variant_json_skip_whitespace(value, index + 1),
+            std::option::Option::Some(b'}') => return std::option::Option::Some(members),
+            _ => return std::option::Option::None,
+        }
+    }
+}
+
+fn raw_variant_json_array_items(value: &[u8]) -> std::option::Option<std::vec::Vec<&[u8]>> {
+    let start = raw_variant_json_skip_whitespace(value, 0);
+    if value.get(start) != std::option::Option::Some(&b'[') {
+        return std::option::Option::None;
+    }
+    let end = match raw_variant_json_value_end(value, start, 0) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return std::option::Option::None,
+    };
+    if raw_variant_json_skip_whitespace(value, end) != value.len() {
+        return std::option::Option::None;
+    }
+    let mut index = raw_variant_json_skip_whitespace(value, start + 1);
+    let mut items = std::vec::Vec::new();
+    if value.get(index) == std::option::Option::Some(&b']') {
+        return std::option::Option::Some(items);
+    }
+    loop {
+        let item_start = index;
+        let item_end = match raw_variant_json_value_end(value, item_start, 1) {
+            std::option::Option::Some(value) => value,
+            std::option::Option::None => return std::option::Option::None,
+        };
+        items.push(&value[item_start..item_end]);
+        index = raw_variant_json_skip_whitespace(value, item_end);
+        match value.get(index).copied() {
+            std::option::Option::Some(b',') => index = raw_variant_json_skip_whitespace(value, index + 1),
+            std::option::Option::Some(b']') => return std::option::Option::Some(items),
+            _ => return std::option::Option::None,
+        }
+    }
+}
+
+fn raw_variant_json_value_end(value: &[u8], start: usize, depth: usize) -> std::option::Option<usize> {
+    if depth > MAX_RAW_VARIANT_JSON_DEPTH {
+        return std::option::Option::None;
+    }
+    let start = raw_variant_json_skip_whitespace(value, start);
+    return match value.get(start).copied() {
+        std::option::Option::Some(b'"') => raw_variant_json_string_end(value, start),
+        std::option::Option::Some(b'{') => raw_variant_json_object_end(value, start, depth + 1),
+        std::option::Option::Some(b'[') => raw_variant_json_array_end(value, start, depth + 1),
+        std::option::Option::Some(b't') => raw_variant_json_literal_end(value, start, b"true"),
+        std::option::Option::Some(b'f') => raw_variant_json_literal_end(value, start, b"false"),
+        std::option::Option::Some(b'n') => raw_variant_json_literal_end(value, start, b"null"),
+        std::option::Option::Some(b'-' | b'0'..=b'9') => raw_variant_json_number_end(value, start),
+        _ => std::option::Option::None,
+    };
+}
+
+fn raw_variant_json_object_end(value: &[u8], start: usize, depth: usize) -> std::option::Option<usize> {
+    let mut index = raw_variant_json_skip_whitespace(value, start + 1);
+    if value.get(index) == std::option::Option::Some(&b'}') {
+        return std::option::Option::Some(index + 1);
+    }
+    loop {
+        index = match raw_variant_json_string_end(value, index) {
+            std::option::Option::Some(value) => value,
+            std::option::Option::None => return std::option::Option::None,
+        };
+        index = raw_variant_json_skip_whitespace(value, index);
+        if value.get(index) != std::option::Option::Some(&b':') {
+            return std::option::Option::None;
+        }
+        index = match raw_variant_json_value_end(value, index + 1, depth) {
+            std::option::Option::Some(value) => value,
+            std::option::Option::None => return std::option::Option::None,
+        };
+        index = raw_variant_json_skip_whitespace(value, index);
+        match value.get(index).copied() {
+            std::option::Option::Some(b',') => index = raw_variant_json_skip_whitespace(value, index + 1),
+            std::option::Option::Some(b'}') => return std::option::Option::Some(index + 1),
+            _ => return std::option::Option::None,
+        }
+    }
+}
+
+fn raw_variant_json_array_end(value: &[u8], start: usize, depth: usize) -> std::option::Option<usize> {
+    let mut index = raw_variant_json_skip_whitespace(value, start + 1);
+    if value.get(index) == std::option::Option::Some(&b']') {
+        return std::option::Option::Some(index + 1);
+    }
+    loop {
+        index = match raw_variant_json_value_end(value, index, depth) {
+            std::option::Option::Some(value) => value,
+            std::option::Option::None => return std::option::Option::None,
+        };
+        index = raw_variant_json_skip_whitespace(value, index);
+        match value.get(index).copied() {
+            std::option::Option::Some(b',') => index = raw_variant_json_skip_whitespace(value, index + 1),
+            std::option::Option::Some(b']') => return std::option::Option::Some(index + 1),
+            _ => return std::option::Option::None,
+        }
+    }
+}
+
+fn raw_variant_json_string_end(value: &[u8], start: usize) -> std::option::Option<usize> {
+    if value.get(start) != std::option::Option::Some(&b'"') {
+        return std::option::Option::None;
+    }
+    let mut index = start + 1;
+    while index < value.len() {
+        match value[index] {
+            b'"' => return std::option::Option::Some(index + 1),
+            b'\\' => {
+                index += 1;
+                let escape = match value.get(index).copied() {
+                    std::option::Option::Some(value) => value,
+                    std::option::Option::None => return std::option::Option::None,
+                };
+                if escape == b'u' {
+                    if index + 4 >= value.len() || !value[index + 1..=index + 4].iter().all(|byte| return byte.is_ascii_hexdigit()) {
+                        return std::option::Option::None;
+                    }
+                    index += 5;
+                    continue;
+                }
+                if !matches!(escape, b'"' | b'\\' | b'/' | b'b' | b'f' | b'n' | b'r' | b't') {
+                    return std::option::Option::None;
+                }
+                index += 1;
+            },
+            0x00..=0x1f => return std::option::Option::None,
+            _ => index += 1,
+        }
+    }
+    return std::option::Option::None;
+}
+
+fn raw_variant_json_literal_end(value: &[u8], start: usize, literal: &[u8]) -> std::option::Option<usize> {
+    let end = match start.checked_add(literal.len()) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return std::option::Option::None,
+    };
+    if value.get(start..end) == std::option::Option::Some(literal) {
+        return std::option::Option::Some(end);
+    }
+    return std::option::Option::None;
+}
+
+fn raw_variant_json_number_end(value: &[u8], start: usize) -> std::option::Option<usize> {
+    let mut index = start;
+    if value.get(index) == std::option::Option::Some(&b'-') {
+        index += 1;
+    }
+    match value.get(index).copied() {
+        std::option::Option::Some(b'0') => index += 1,
+        std::option::Option::Some(b'1'..=b'9') => {
+            index += 1;
+            while matches!(value.get(index).copied(), std::option::Option::Some(b'0'..=b'9')) {
+                index += 1;
+            }
+        },
+        _ => return std::option::Option::None,
+    }
+    if value.get(index) == std::option::Option::Some(&b'.') {
+        index += 1;
+        let fraction_start = index;
+        while matches!(value.get(index).copied(), std::option::Option::Some(b'0'..=b'9')) {
+            index += 1;
+        }
+        if index == fraction_start {
+            return std::option::Option::None;
+        }
+    }
+    if matches!(value.get(index).copied(), std::option::Option::Some(b'e' | b'E')) {
+        index += 1;
+        if matches!(value.get(index).copied(), std::option::Option::Some(b'+' | b'-')) {
+            index += 1;
+        }
+        let exponent_start = index;
+        while matches!(value.get(index).copied(), std::option::Option::Some(b'0'..=b'9')) {
+            index += 1;
+        }
+        if index == exponent_start {
+            return std::option::Option::None;
+        }
+    }
+    return std::option::Option::Some(index);
+}
+
+fn raw_variant_json_skip_whitespace(value: &[u8], mut index: usize) -> usize {
+    while matches!(value.get(index).copied(), std::option::Option::Some(b' ' | b'\n' | b'\r' | b'\t')) {
+        index += 1;
+    }
+    return index;
+}
+
+fn raw_variant_json_is_string(value: &[u8]) -> bool {
+    return raw_variant_json_string_end(value, 0) == std::option::Option::Some(value.len());
+}
+
 fn raw_variant_model_error(field: &'static str) -> crate::Error {
     return crate::Error::new(crate::ERROR_CODE_RAW_MODEL_INVALID, "invalid RAW transaction variant model").with_context("field", field);
 }
diff --git a/crates/ksp-store-api/tests/dependency_boundary.rs b/crates/ksp-store-api/tests/dependency_boundary.rs
index a2a8cc9..3d57384 100644
--- a/crates/ksp-store-api/tests/dependency_boundary.rs
+++ b/crates/ksp-store-api/tests/dependency_boundary.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-api/tests/dependency_boundary.rs
-// version: 7
+// version: 8
 
 //! Dependency canaries for the Store API RAW foundation.
 
@@ -97,6 +97,7 @@ fn pre_006_source_boundary_keeps_models_and_capabilities_backend_free() {
             "ksp_onchain_transport_lib",
             "ksp_program_api",
             "serde::",
+            "serde_json::",
             "sqlx::",
             "tokio::",
             "tokio_postgres::",
diff --git a/crates/ksp-store-api/tests/public_api.rs b/crates/ksp-store-api/tests/public_api.rs
index 1859418..0a7b9c4 100644
--- a/crates/ksp-store-api/tests/public_api.rs
+++ b/crates/ksp-store-api/tests/public_api.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-api/tests/public_api.rs
-// version: 9
+// version: 10
 
 //! Integration canaries for the public `ksp-store-api` surface.
 
@@ -208,3 +208,10 @@ fn public_v0_3_8_pre_003_inspection_contracts_are_backend_neutral_and_dyn_compat
     assert!(account_observation_inspection.is_none());
     return;
 }
+
+#[test]
+fn public_v0_3_16_pre_005_variant_comparator_is_available_from_crate_root() {
+    let comparator = ksp_store_api::compare_raw_transaction_variants;
+    let _ = comparator;
+    return;
+}
diff --git a/crates/ksp-store-api/tests/release_completeness.rs b/crates/ksp-store-api/tests/release_completeness.rs
index ef7634f..de8370c 100644
--- a/crates/ksp-store-api/tests/release_completeness.rs
+++ b/crates/ksp-store-api/tests/release_completeness.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-api/tests/release_completeness.rs
-// version: 5
+// version: 6
 
 //! Release-level boundary and completeness canaries for the backend-neutral Store API RAW surface.
 #[test]
@@ -87,6 +87,7 @@ fn v0_3_8_pre_003_exact_crate_root_export_inventory_is_stable() {
         "pub use self::model::raw_retention::RawTransactionRetentionTransition;",
         "pub use self::model::raw_retention::RawTransactionTombstone;",
         "pub use self::model::raw_transaction::RawTransaction;",
+        "pub use self::model::raw_transaction::compare_raw_transaction_variants;",
         "pub use self::model::raw_transaction::RawTransactionConflictStatus;",
         "pub use self::model::raw_transaction::RawTransactionObservation;",
         "pub use self::model::raw_transaction::RawTransactionReference;",
diff --git a/crates/ksp-store-api/unit_tests/model/raw_transaction.rs b/crates/ksp-store-api/unit_tests/model/raw_transaction.rs
index 5f0fde9..69a3c02 100644
--- a/crates/ksp-store-api/unit_tests/model/raw_transaction.rs
+++ b/crates/ksp-store-api/unit_tests/model/raw_transaction.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-api/unit_tests/model/raw_transaction.rs
-// version: 3
+// version: 5
 
 fn network() -> std::option::Option<crate::RawNetworkId> {
     return match crate::RawNetworkId::new("mainnet".to_owned()) {
@@ -140,3 +140,121 @@ fn transaction_variant_codes_and_outcomes_are_stable_backend_neutral_contracts()
     assert_ne!(crate::RawTransactionVariantWriteOutcome::QuarantinedConflict, crate::RawTransactionVariantWriteOutcome::PromotedCompatibleMoreComplete);
     return;
 }
+
+fn comparison_transaction(payload_bytes: &[u8], hash_byte: u8) -> std::option::Option<crate::RawTransaction> {
+    let network = match network() {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return std::option::Option::None,
+    };
+    let format = match crate::RawFormatId::new("ksp.solana.raw_transaction".to_owned()) {
+        std::result::Result::Ok(value) => value,
+        std::result::Result::Err(_) => return std::option::Option::None,
+    };
+    let payload = match crate::RawPayload::try_new(format, 1, payload_bytes.to_vec().into_boxed_slice(), crate::RawContentHash::new([hash_byte; 32])) {
+        std::result::Result::Ok(value) => value,
+        std::result::Result::Err(_) => return std::option::Option::None,
+    };
+    let reference = crate::RawTransactionReference::new(network, crate::RawTransactionSignature::new([21_u8; 64]));
+    return std::option::Option::Some(crate::RawTransaction::new(reference, 88, std::option::Option::None, payload));
+}
+
+fn comparison_relation(
+    canonical_payload: &[u8],
+    canonical_hash: u8,
+    incoming_payload: &[u8],
+    incoming_hash: u8,
+) -> std::option::Option<crate::RawTransactionVariantComparison> {
+    let canonical = match comparison_transaction(canonical_payload, canonical_hash) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return std::option::Option::None,
+    };
+    let incoming = match comparison_transaction(incoming_payload, incoming_hash) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return std::option::Option::None,
+    };
+    return crate::compare_raw_transaction_variants(&canonical, &incoming).ok();
+}
+
+#[test]
+fn v0_3_16_pre_005_comparator_proves_bidirectional_log_messages_truncation_only() {
+    let full = br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Program Vote111 success"],"rewards":[]},"version":0,"transactionIndex":7}"#;
+    let truncated = br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated"],"rewards":[]},"version":0,"transactionIndex":7}"#;
+    let less = match comparison_relation(full, 31, truncated, 32) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return,
+    };
+    assert_eq!(less.relation(), crate::RawTransactionVariantRelation::CompatibleLessComplete);
+    assert_eq!(less.reason(), crate::RawTransactionVariantRelationReason::IncomingLogMessagesTruncated);
+    let more = match comparison_relation(truncated, 32, full, 31) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return,
+    };
+    assert_eq!(more.relation(), crate::RawTransactionVariantRelation::CompatibleMoreComplete);
+    assert_eq!(more.reason(), crate::RawTransactionVariantRelationReason::CanonicalLogMessagesTruncated);
+    return;
+}
+
+#[test]
+fn v0_3_16_pre_005_comparator_rejects_unproved_log_shortening_and_marker_shapes() {
+    let full = br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["a","b","c"],"rewards":[]},"version":0}"#;
+    let shorter = br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["a","b"],"rewards":[]},"version":0}"#;
+    let marker_not_last =
+        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["a","Log truncated","c"],"rewards":[]},"version":0}"#;
+    let marker_not_exact =
+        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["a","b","Log truncated by provider"],"rewards":[]},"version":0}"#;
+    let bad_prefix =
+        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["a","changed","Log truncated"],"rewards":[]},"version":0}"#;
+    let candidates: [&[u8]; 4] = [shorter, marker_not_last, marker_not_exact, bad_prefix];
+    for (index, candidate) in candidates.iter().enumerate() {
+        let hash_offset = match u8::try_from(index) {
+            std::result::Result::Ok(value) => value,
+            std::result::Result::Err(_) => return,
+        };
+        let comparison = match comparison_relation(full, 40, candidate, 41 + hash_offset) {
+            std::option::Option::Some(value) => value,
+            std::option::Option::None => return,
+        };
+        assert_eq!(comparison.relation(), crate::RawTransactionVariantRelation::Conflict);
+        assert_eq!(comparison.reason(), crate::RawTransactionVariantRelationReason::CanonicalPayloadConflict);
+    }
+    return;
+}
+
+#[test]
+fn v0_3_16_pre_005_comparator_is_fail_closed_for_optional_and_other_payload_differences() {
+    let canonical = br#"{"transaction":["AQID","base64"],"meta":{"fee":5000,"logMessages":["a"],"returnData":null},"version":0}"#;
+    let optional_value =
+        br#"{"transaction":["AQID","base64"],"meta":{"fee":5000,"logMessages":["a"],"returnData":{"data":["","base64"],"programId":"Vote111"}},"version":0}"#;
+    let concrete_conflict = br#"{"transaction":["AQID","base64"],"meta":{"fee":5001,"logMessages":["a"],"returnData":null},"version":0}"#;
+    let optional = match comparison_relation(canonical, 50, optional_value, 51) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return,
+    };
+    assert_eq!(optional.relation(), crate::RawTransactionVariantRelation::Incomparable);
+    assert_eq!(optional.reason(), crate::RawTransactionVariantRelationReason::UnsupportedCanonicalDifference);
+    let conflict = match comparison_relation(canonical, 50, concrete_conflict, 52) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return,
+    };
+    assert_eq!(conflict.relation(), crate::RawTransactionVariantRelation::Conflict);
+    assert_eq!(conflict.reason(), crate::RawTransactionVariantRelationReason::CanonicalPayloadConflict);
+    return;
+}
+
+#[test]
+fn v0_3_16_pre_005_comparator_uses_exact_bytes_and_detects_hash_collision_without_hash_equality_shortcut() {
+    let canonical = br#"{"transaction":["AQID","base64"],"meta":{"logMessages":["a"]}}"#;
+    let same_bytes = match comparison_relation(canonical, 60, canonical, 61) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return,
+    };
+    assert_eq!(same_bytes.relation(), crate::RawTransactionVariantRelation::Exact);
+    let different = br#"{"transaction":["AQID","base64"],"meta":{"logMessages":["b"]}}"#;
+    let collision = match comparison_relation(canonical, 62, different, 62) {
+        std::option::Option::Some(value) => value,
+        std::option::Option::None => return,
+    };
+    assert_eq!(collision.relation(), crate::RawTransactionVariantRelation::Conflict);
+    assert_eq!(collision.reason(), crate::RawTransactionVariantRelationReason::ContentHashCollision);
+    return;
+}
diff --git a/crates/ksp-store-postgres-lib/src/raw_transaction.rs b/crates/ksp-store-postgres-lib/src/raw_transaction.rs
index 6e2741a..eb8f7c8 100644
--- a/crates/ksp-store-postgres-lib/src/raw_transaction.rs
+++ b/crates/ksp-store-postgres-lib/src/raw_transaction.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-postgres-lib/src/raw_transaction.rs
-// version: 11
+// version: 12
 
 pub(crate) mod cursor;
 
@@ -712,7 +712,7 @@ pub(crate) async fn persist_raw_transaction_acquisition(
         };
         match comparison {
             ExistingTransactionMatch::Active => (ksp_store_api::RawEntityWriteOutcome::AlreadyPresent, canonical_variant_id),
-            ExistingTransactionMatch::ActiveIncomingTruncatedLogs => {
+            ExistingTransactionMatch::ActiveCompatibleLessComplete => {
                 let variant_result = persist_or_reuse_native_transaction_variant(&sql_transaction, &raw_transaction, linked_at).await;
                 let variant_id = match variant_result {
                     std::result::Result::Ok(value) => value,
@@ -896,7 +896,7 @@ pub(crate) async fn transition_raw_transaction_retention(
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 enum ExistingTransactionMatch {
     Active,
-    ActiveIncomingTruncatedLogs,
+    ActiveCompatibleLessComplete,
     Purged,
 }
 
@@ -1439,87 +1439,24 @@ fn compare_existing_transaction(
         std::result::Result::Ok(std::option::Option::None) => return std::result::Result::Err(data_invalid("raw_acquisition_active_shape")),
         std::result::Result::Err(error) => return std::result::Result::Err(error),
     };
-    if raw_transactions_equal(&stored, incoming) {
-        return std::result::Result::Ok(ExistingTransactionMatch::Active);
-    }
-    if raw_transaction_incoming_truncated_log_messages_compatible(&stored, incoming) {
-        log_raw_transaction_compatible_truncated_log_messages(network, &stored, incoming);
-        return std::result::Result::Ok(ExistingTransactionMatch::ActiveIncomingTruncatedLogs);
-    }
-    log_raw_transaction_content_conflict(network, &stored, incoming);
-    return std::result::Result::Err(conflict("raw_acquisition_content_conflict"));
-}
-
-fn raw_transaction_incoming_truncated_log_messages_compatible(stored: &ksp_store_api::RawTransaction, incoming: &ksp_store_api::RawTransaction) -> bool {
-    if stored.reference() != incoming.reference()
-        || stored.slot() != incoming.slot()
-        || stored.block_time() != incoming.block_time()
-        || stored.payload().format_id() != incoming.payload().format_id()
-        || stored.payload().format_version() != incoming.payload().format_version()
-    {
-        return false;
-    }
-    let stored_payload = serde_json::from_slice::<serde_json::Value>(stored.payload().bytes());
-    let incoming_payload = serde_json::from_slice::<serde_json::Value>(incoming.payload().bytes());
-    let (stored_payload, incoming_payload) = match (stored_payload, incoming_payload) {
-        (std::result::Result::Ok(serde_json::Value::Object(stored)), std::result::Result::Ok(serde_json::Value::Object(incoming))) => (stored, incoming),
-        _ => return false,
+    let comparison = match ksp_store_api::compare_raw_transaction_variants(&stored, incoming) {
+        std::result::Result::Ok(value) => value,
+        std::result::Result::Err(_) => return std::result::Result::Err(data_invalid("raw_acquisition_variant_comparison")),
     };
-    if stored_payload.get("transaction") != incoming_payload.get("transaction")
-        || stored_payload.get("version") != incoming_payload.get("version")
-        || stored_payload.get("transactionIndex") != incoming_payload.get("transactionIndex")
-        || json_object_other_fields_mismatch(&stored_payload, &incoming_payload, RAW_TRANSACTION_CONTENT_CONFLICT_PAYLOAD_FIELDS.as_slice())
-    {
-        return false;
-    }
-    let (stored_meta, incoming_meta) = match (stored_payload.get("meta"), incoming_payload.get("meta")) {
-        (std::option::Option::Some(serde_json::Value::Object(stored)), std::option::Option::Some(serde_json::Value::Object(incoming))) => (stored, incoming),
-        _ => return false,
-    };
-    if raw_meta_other_than_log_messages_mismatch(stored_meta, incoming_meta) {
-        return false;
-    }
-    let (stored_logs, incoming_logs) = match (stored_meta.get("logMessages"), incoming_meta.get("logMessages")) {
-        (std::option::Option::Some(serde_json::Value::Array(stored)), std::option::Option::Some(serde_json::Value::Array(incoming))) => {
-            (stored.as_slice(), incoming.as_slice())
+    return match comparison.relation() {
+        ksp_store_api::RawTransactionVariantRelation::Exact => std::result::Result::Ok(ExistingTransactionMatch::Active),
+        ksp_store_api::RawTransactionVariantRelation::CompatibleLessComplete => {
+            log_raw_transaction_compatible_truncated_log_messages(network, &stored, incoming);
+            std::result::Result::Ok(ExistingTransactionMatch::ActiveCompatibleLessComplete)
         },
-        _ => return false,
+        ksp_store_api::RawTransactionVariantRelation::CompatibleMoreComplete
+        | ksp_store_api::RawTransactionVariantRelation::Conflict
+        | ksp_store_api::RawTransactionVariantRelation::Incomparable => {
+            log_raw_transaction_content_conflict(network, &stored, incoming);
+            std::result::Result::Err(conflict("raw_acquisition_content_conflict"))
+        },
+        _ => std::result::Result::Err(data_invalid("raw_acquisition_variant_relation")),
     };
-    return raw_log_messages_incoming_truncated_compatible(stored_logs, incoming_logs);
-}
-
-fn raw_meta_other_than_log_messages_mismatch(
-    stored: &serde_json::Map<std::string::String, serde_json::Value>,
-    incoming: &serde_json::Map<std::string::String, serde_json::Value>,
-) -> bool {
-    let stored_without_logs = stored.iter().filter(|(key, _)| return key.as_str() != "logMessages").collect::<std::collections::BTreeMap<_, _>>();
-    let incoming_without_logs = incoming.iter().filter(|(key, _)| return key.as_str() != "logMessages").collect::<std::collections::BTreeMap<_, _>>();
-    return stored_without_logs != incoming_without_logs;
-}
-
-fn raw_log_messages_incoming_truncated_compatible(stored: &[serde_json::Value], incoming: &[serde_json::Value]) -> bool {
-    if raw_log_messages_exact_truncation_marker_count(stored) != 0 {
-        return false;
-    }
-    let marker_index = match incoming.iter().position(raw_log_message_is_exact_truncation_marker) {
-        std::option::Option::Some(value) => value,
-        std::option::Option::None => return false,
-    };
-    if raw_log_messages_exact_truncation_marker_count(incoming) != 1 || marker_index >= stored.len() {
-        return false;
-    }
-    if incoming[..marker_index] != stored[..marker_index] {
-        return false;
-    }
-    return true;
-}
-
-fn raw_log_messages_exact_truncation_marker_count(values: &[serde_json::Value]) -> usize {
-    return values.iter().filter(|value| return raw_log_message_is_exact_truncation_marker(value)).count();
-}
-
-fn raw_log_message_is_exact_truncation_marker(value: &serde_json::Value) -> bool {
-    return matches!(value, serde_json::Value::String(line) if line == "Log truncated");
 }
 
 fn raw_transaction_content_conflict_diagnostic(
@@ -1863,16 +1800,6 @@ async fn log_raw_transaction_content_conflict_provenance(
     return;
 }
 
-fn raw_transactions_equal(left: &ksp_store_api::RawTransaction, right: &ksp_store_api::RawTransaction) -> bool {
-    return left.reference() == right.reference()
-        && left.slot() == right.slot()
-        && left.block_time() == right.block_time()
-        && left.payload().format_id() == right.payload().format_id()
-        && left.payload().format_version() == right.payload().format_version()
-        && left.payload().content_hash() == right.payload().content_hash()
-        && left.payload().bytes() == right.payload().bytes();
-}
-
 async fn rehydrate_transaction(
     sql_transaction: &deadpool_postgres::Transaction<'_>,
     raw_transaction: &ksp_store_api::RawTransaction,
diff --git a/crates/ksp-store-postgres-lib/tests/hardening_completeness.rs b/crates/ksp-store-postgres-lib/tests/hardening_completeness.rs
index e194e4e..9b1c09f 100644
--- a/crates/ksp-store-postgres-lib/tests/hardening_completeness.rs
+++ b/crates/ksp-store-postgres-lib/tests/hardening_completeness.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-postgres-lib/tests/hardening_completeness.rs
-// version: 27
+// version: 28
 
 #![warn(missing_docs)]
 #![deny(unreachable_pub)]
@@ -594,7 +594,7 @@ fn v0_3_15_pre_012_fix_004_content_conflict_diagnostic_is_field_only_bounded_and
     let Some(start) = start else {
         return;
     };
-    let end = source[start..].find("fn raw_transactions_equal(");
+    let end = source[start..].find("async fn rehydrate_transaction(");
     assert!(end.is_some(), "missing RAW conflict logger end marker");
     let Some(end) = end else {
         return;
@@ -645,33 +645,42 @@ fn v0_3_15_pre_014_content_conflict_diagnostic_exposes_only_block_slot_and_bound
 }
 
 #[test]
-fn v0_3_15_pre_014_fix_001_truncated_log_compatibility_is_narrow_and_keeps_canonical_content() {
+fn v0_3_16_pre_005_postgres_uses_shared_fail_closed_variant_comparator_without_promotion() {
     let source = include_str!("../src/raw_transaction.rs");
     for required in [
-        "ActiveIncomingTruncatedLogs",
+        "ksp_store_api::compare_raw_transaction_variants",
+        "RawTransactionVariantRelation::Exact",
+        "RawTransactionVariantRelation::CompatibleLessComplete",
+        "RawTransactionVariantRelation::CompatibleMoreComplete",
+        "RawTransactionVariantRelation::Conflict",
+        "RawTransactionVariantRelation::Incomparable",
+        "ExistingTransactionMatch::ActiveCompatibleLessComplete",
+        "raw_acquisition_content_conflict",
+    ] {
+        assert!(source.contains(required), "missing shared comparator integration guard: {required}");
+    }
+    for forbidden in [
         "raw_transaction_incoming_truncated_log_messages_compatible",
         "raw_meta_other_than_log_messages_mismatch",
         "raw_log_messages_incoming_truncated_compatible",
         "raw_log_message_is_exact_truncation_marker",
-        "marker_index >= stored.len()",
-        "incoming[..marker_index] != stored[..marker_index]",
-        "PostgreSQL Store accepted compatible truncated RAW transaction logs without replacing canonical content",
     ] {
-        assert!(source.contains(required), "missing narrow truncated-log compatibility guard: {required}");
+        assert!(!source.contains(forbidden), "backend-private convergence heuristic survived pre.005: {forbidden}");
     }
     let start = source.find("fn compare_existing_transaction(");
-    assert!(start.is_some(), "missing fix.001 existing-transaction comparison path");
+    assert!(start.is_some(), "missing pre.005 existing-transaction comparison path");
     let Some(start) = start else {
         return;
     };
-    let end = source[start..].find("fn raw_transaction_incoming_truncated_log_messages_compatible(");
-    assert!(end.is_some(), "missing fix.001 compatibility helper boundary");
+    let end = source[start..].find("fn raw_transaction_content_conflict_diagnostic(");
+    assert!(end.is_some(), "missing pre.005 comparison boundary");
     let Some(end) = end else {
         return;
     };
     let comparison = &source[start..start + end];
-    assert!(comparison.contains("ExistingTransactionMatch::ActiveIncomingTruncatedLogs"));
+    assert!(comparison.contains("CompatibleLessComplete"));
+    assert!(comparison.contains("CompatibleMoreComplete"));
     assert!(!comparison.contains("UPDATE ksp_raw_transactions SET payload"));
-    assert!(!comparison.contains("DELETE FROM ksp_raw_transactions"));
+    assert!(!comparison.contains("canonical_revision"));
     return;
 }
diff --git a/crates/ksp-store-postgres-lib/tests/v003_variant_persistence.rs b/crates/ksp-store-postgres-lib/tests/v003_variant_persistence.rs
index 2fc2f55..7d0b4c0 100644
--- a/crates/ksp-store-postgres-lib/tests/v003_variant_persistence.rs
+++ b/crates/ksp-store-postgres-lib/tests/v003_variant_persistence.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-postgres-lib/tests/v003_variant_persistence.rs
-// version: 1
+// version: 2
 
 #![warn(missing_docs)]
 #![deny(unreachable_pub)]
@@ -59,9 +59,11 @@ fn v0_3_16_pre_004_legacy_observation_without_mapping_is_not_fabricated() {
 }
 
 #[test]
-fn v0_3_16_pre_004_keeps_comparator_and_durable_conflict_scope_deferred() {
+fn v0_3_16_pre_005_shared_comparator_is_active_but_durable_conflict_and_promotion_stay_deferred() {
     let source = include_str!("../src/raw_transaction.rs");
-    assert!(!source.contains("RawTransactionVariantRelation::"));
+    assert!(source.contains("ksp_store_api::compare_raw_transaction_variants"));
+    assert!(source.contains("ksp_store_api::RawTransactionVariantRelation::CompatibleLessComplete"));
+    assert!(source.contains("ksp_store_api::RawTransactionVariantRelation::CompatibleMoreComplete"));
     assert!(!source.contains("INSERT INTO ksp_raw_transaction_conflicts"));
     assert!(!source.contains("UPDATE ksp_raw_transaction_canonical_selectors SET canonical_variant_id"));
     return;
diff --git a/crates/ksp-store-postgres-lib/unit_tests/raw_transaction.rs b/crates/ksp-store-postgres-lib/unit_tests/raw_transaction.rs
index a4fc746..4ca07b0 100644
--- a/crates/ksp-store-postgres-lib/unit_tests/raw_transaction.rs
+++ b/crates/ksp-store-postgres-lib/unit_tests/raw_transaction.rs
@@ -1,5 +1,5 @@
 // file: crates/ksp-store-postgres-lib/unit_tests/raw_transaction.rs
-// version: 11
+// version: 12
 
 fn network() -> ksp_store_api::RawNetworkId {
     return match ksp_store_api::RawNetworkId::new("devnet") {
@@ -458,7 +458,7 @@ fn v0_3_15_pre_014_log_messages_conflict_diagnostic_distinguishes_prefix_truncat
 }
 
 #[test]
-fn v0_3_15_pre_014_fix_001_incoming_truncated_logs_are_compatible_only_when_missing_middle_is_proven() {
+fn v0_3_16_pre_005_shared_comparator_accepts_only_proved_incoming_truncation_in_postgres_path() {
     let stored = raw_transaction(
         9,
         br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Program log: detail-a","Program log: detail-b","Program Vote111 success"],"rewards":[]},"version":0,"transactionIndex":7}"#,
@@ -466,10 +466,15 @@ fn v0_3_15_pre_014_fix_001_incoming_truncated_logs_are_compatible_only_when_miss
     );
     let incoming = raw_transaction(
         9,
-        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated","Program Vote111 success"],"rewards":[]},"version":0,"transactionIndex":7}"#,
+        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated"],"rewards":[]},"version":0,"transactionIndex":7}"#,
         8,
     );
-    assert!(super::raw_transaction_incoming_truncated_log_messages_compatible(&stored, &incoming));
+    let relation = ksp_store_api::compare_raw_transaction_variants(&stored, &incoming);
+    let relation = match relation {
+        std::result::Result::Ok(value) => value,
+        std::result::Result::Err(_) => return,
+    };
+    assert_eq!(relation.relation(), ksp_store_api::RawTransactionVariantRelation::CompatibleLessComplete);
     let mut stored_row = transaction_row("full");
     stored_row.signature = stored.reference().signature().as_bytes().to_vec();
     stored_row.slot_text = stored.slot().to_string();
@@ -479,12 +484,12 @@ fn v0_3_15_pre_014_fix_001_incoming_truncated_logs_are_compatible_only_when_miss
     stored_row.content_hash = stored.payload().content_hash().as_bytes().to_vec();
     stored_row.payload = std::option::Option::Some(stored.payload().bytes().to_vec());
     let comparison = super::compare_existing_transaction(&network(), stored_row, &incoming);
-    assert!(matches!(comparison, std::result::Result::Ok(super::ExistingTransactionMatch::ActiveIncomingTruncatedLogs)));
+    assert!(matches!(comparison, std::result::Result::Ok(super::ExistingTransactionMatch::ActiveCompatibleLessComplete)));
     return;
 }
 
 #[test]
-fn v0_3_15_pre_014_fix_001_truncated_log_compatibility_rejects_unproven_or_reverse_changes() {
+fn v0_3_16_pre_005_shared_comparator_rejects_unproved_shapes_and_defers_more_complete_promotion() {
     let stored = raw_transaction(
         9,
         br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Program log: detail-a","Program log: detail-b","Program Vote111 success"],"rewards":[]},"version":0,"transactionIndex":7}"#,
@@ -492,34 +497,52 @@ fn v0_3_15_pre_014_fix_001_truncated_log_compatibility_rejects_unproven_or_rever
     );
     let bad_prefix = raw_transaction(
         9,
-        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: changed","Log truncated","Program Vote111 success"],"rewards":[]},"version":0,"transactionIndex":7}"#,
+        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: changed","Log truncated"],"rewards":[]},"version":0,"transactionIndex":7}"#,
         8,
     );
-    assert!(!super::raw_transaction_incoming_truncated_log_messages_compatible(&stored, &bad_prefix));
     let post_marker_material = raw_transaction(
         9,
         br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated","Program Other111 success"],"rewards":[]},"version":0,"transactionIndex":7}"#,
         8,
     );
-    assert!(super::raw_transaction_incoming_truncated_log_messages_compatible(&stored, &post_marker_material));
     let other_meta = raw_transaction(
         9,
-        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5001,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated","Program Vote111 success"],"rewards":[]},"version":0,"transactionIndex":7}"#,
+        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5001,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated"],"rewards":[]},"version":0,"transactionIndex":7}"#,
         8,
     );
-    assert!(!super::raw_transaction_incoming_truncated_log_messages_compatible(&stored, &other_meta));
     let non_exact_marker = raw_transaction(
         9,
         br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated by provider"],"rewards":[]},"version":0,"transactionIndex":7}"#,
         8,
     );
-    assert!(!super::raw_transaction_incoming_truncated_log_messages_compatible(&stored, &non_exact_marker));
+    for candidate in [&bad_prefix, &post_marker_material, &other_meta, &non_exact_marker] {
+        let relation = match ksp_store_api::compare_raw_transaction_variants(&stored, candidate) {
+            std::result::Result::Ok(value) => value,
+            std::result::Result::Err(_) => return,
+        };
+        assert_ne!(relation.relation(), ksp_store_api::RawTransactionVariantRelation::CompatibleLessComplete);
+        assert_ne!(relation.relation(), ksp_store_api::RawTransactionVariantRelation::CompatibleMoreComplete);
+    }
     let stored_truncated = raw_transaction(
         9,
-        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated","Program Vote111 success"],"rewards":[]},"version":0,"transactionIndex":7}"#,
+        br#"{"transaction":["AQID","base64"],"meta":{"err":null,"fee":5000,"logMessages":["Program Vote111 invoke [1]","Program log: stable","Log truncated"],"rewards":[]},"version":0,"transactionIndex":7}"#,
         8,
     );
-    assert!(!super::raw_transaction_incoming_truncated_log_messages_compatible(&stored_truncated, &stored));
+    let more = match ksp_store_api::compare_raw_transaction_variants(&stored_truncated, &stored) {
+        std::result::Result::Ok(value) => value,
+        std::result::Result::Err(_) => return,
+    };
+    assert_eq!(more.relation(), ksp_store_api::RawTransactionVariantRelation::CompatibleMoreComplete);
+    let mut stored_row = transaction_row("full");
+    stored_row.signature = stored_truncated.reference().signature().as_bytes().to_vec();
+    stored_row.slot_text = stored_truncated.slot().to_string();
+    stored_row.block_time_unix_millis = stored_truncated.block_time().and_then(|value| return i64::try_from(value.unix_millis()).ok());
+    stored_row.format_id = stored_truncated.payload().format_id().as_str().to_owned();
+    stored_row.format_version = i64::from(stored_truncated.payload().format_version());
+    stored_row.content_hash = stored_truncated.payload().content_hash().as_bytes().to_vec();
+    stored_row.payload = std::option::Option::Some(stored_truncated.payload().bytes().to_vec());
+    let comparison = super::compare_existing_transaction(&network(), stored_row, &stored);
+    assert!(matches!(comparison, std::result::Result::Err(error) if error.phase() == "raw_acquisition_content_conflict"));
     return;
 }
 
diff --git a/deltas/0.3.16/pre.005-fix.001.md b/deltas/0.3.16/pre.005-fix.001.md
new file mode 100644
index 0000000..d8c6bd3
--- /dev/null
+++ b/deltas/0.3.16/pre.005-fix.001.md
@@ -0,0 +1,77 @@
+<!-- file: deltas/0.3.16/pre.005-fix.001.md -->
+<!-- version: 1 -->
+
+# Delta `0.3.16-pre.005-fix.001` — conformité Clippy et canari de scope `pre.005`
+
+## Base requise
+
+```text
+0.3.16-pre.005 appliquée
+workspace.package.version = 0.3.16-pre.5
+```
+
+Le gate opérateur de `pre.005` confirme que les audits Rust/export/KSP/Markdown sont propres, que `cargo check --workspace` passe et que les suites ciblées exécutées sont fonctionnellement vertes à l'exception d'un canari PostgreSQL devenu obsolète. Clippy `-D warnings` refuse toutefois treize usages de l'opérateur `?` sous la règle workspace `clippy::question_mark_used` : dix dans le scanner JSON privé du comparateur et trois dans ses helpers de tests.
+
+Le seul échec de test est `v0_3_16_pre_004_keeps_comparator_and_durable_conflict_scope_deferred`, qui interdit encore toute référence à `RawTransactionVariantRelation::` alors que `pre.005` a précisément introduit le comparateur partagé et ses relations dans le chemin PostgreSQL.
+
+## Version
+
+Cette correction modifie du Rust :
+
+```text
+workspace.package.version = 0.3.16-pre.5.fix.1
+```
+
+## Corrections
+
+Le correctif ne modifie aucune règle métier du comparateur :
+
+- les dix propagations `Option` par `?` du scanner JSON privé sont remplacées par des `match` explicites qui retournent `None` sur le même chemin d'échec ;
+- les trois usages `?` des helpers de tests Store API sont remplacés par les mêmes retours explicites ;
+- aucune autorisation locale `#[allow(clippy::question_mark_used)]` n'est ajoutée ;
+- aucune dépendance runtime n'est ajoutée à `ksp-store-api` ;
+- le canari V003 hérité de `pre.004` est mis à jour pour exiger désormais l'appel à `ksp_store_api::compare_raw_transaction_variants` et les relations `CompatibleLessComplete` / `CompatibleMoreComplete` ;
+- ce même canari continue d'interdire l'écriture dans `ksp_raw_transaction_conflicts` et toute promotion du selector canonique avant les tranches prévues.
+
+## Invariants conservés
+
+La sémantique de `pre.005` reste inchangée :
+
+```text
+Exact                       -> idempotence canonique
+CompatibleLessComplete      -> canonique conservé, variante entrante persistée/rattachée
+CompatibleMoreComplete      -> reconnue mais fail-closed jusqu'à pre.006
+Conflict / Incomparable     -> conflit existant sans conflict case durable avant pre.007
+```
+
+La preuve `logMessages` reste strictement bidirectionnelle, avec marqueur exact `"Log truncated"`, unique et terminal, préfixe byte-identique et matériel supplémentaire obligatoire du côté complet.
+
+Aucune migration SQL, ressource V003, promotion canonique, `canonical_revision`, journal de transition ou conflit durable n'est modifié par ce fix.
+
+## Validation exécutée lors de la génération
+
+Les scripts Python réels du checkout complet sont exécutés sur l'état final puis sur le ZIP rejoué sur une copie fraîche de `pre.005`.
+
+Le toolchain Rust n'est pas disponible dans l'environnement de génération ; les gates Cargo restent opérateur.
+
+## Validation opérateur demandée
+
+```bash
+cargo fmt --all
+cargo fmt --all -- --check
+
+python3 scripts/audit_rust_workspace_rules.py
+python3 scripts/audit_markdown_tables.py README.md RULES.md ROADMAP.md CHANGELOG.md docs prompts crates deltas
+
+cargo check --workspace
+cargo clippy --workspace --all-targets --all-features -- -D warnings
+
+cargo test -p ksp-store-api --all-targets --all-features
+cargo test -p ksp-store-postgres-lib --all-targets --all-features
+```
+
+Les trois preuves PostgreSQL live restent opt-in.
+
+## Suite
+
+Après gate propre : `0.3.16-pre.006` — selector canonique, promotion atomique de `CompatibleMoreComplete`, `canonical_revision`, projection V001 cohérente et conservation de l'ancien canonique.
diff --git a/deltas/0.3.16/pre.005.md b/deltas/0.3.16/pre.005.md
new file mode 100644
index 0000000..bea4fd5
--- /dev/null
+++ b/deltas/0.3.16/pre.005.md
@@ -0,0 +1,173 @@
+<!-- file: deltas/0.3.16/pre.005.md -->
+<!-- version: 1 -->
+
+# Delta `0.3.16-pre.005` — comparateur backend-neutral des variantes RAW
+
+## Base requise
+
+```text
+0.3.16-pre.004 appliquée
+workspace.package.version = 0.3.16-pre.4
+```
+
+Le gate opérateur de `pre.004` est confirmé propre : audits Rust/export/KSP/Markdown, `cargo check --workspace`, Clippy `-D warnings`, 85 tests unitaires `ksp-store-postgres-lib` et toutes les suites d'intégration ciblées passent. Les trois preuves PostgreSQL live restent opt-in.
+
+## Version
+
+Cette tranche modifie le contrat Store API et son intégration PostgreSQL :
+
+```text
+workspace.package.version = 0.3.16-pre.5
+```
+
+## Portée
+
+Cette tranche rend effectif le comparateur pur backend-neutral prévu depuis `pre.002`.
+
+`ksp-store-api` expose désormais :
+
+```text
+compare_raw_transaction_variants(canonical, incoming)
+    -> RawTransactionVariantComparison
+```
+
+Le comparateur produit exclusivement les relations déjà figées :
+
+```text
+Exact
+CompatibleLessComplete
+CompatibleMoreComplete
+Conflict
+Incomparable
+```
+
+Le comparateur n'ajoute aucune dépendance runtime à `ksp-store-api`. En particulier, `serde_json` reste interdit par le canari de dépendances existant. L'analyse du payload RAW v1 utilise un scanner JSON privé, borné en profondeur et fondé uniquement sur `std`.
+
+## Ordre de décision
+
+La comparaison est fail-closed et applique l'ordre suivant :
+
+1. les deux variantes doivent appartenir à la même identité `network + signature`, sinon l'appel est invalide ;
+2. `slot` différent -> `Conflict / SlotMismatch` ;
+3. `block_time` différent -> `Conflict / BlockTimeMismatch` ;
+4. format id/version différent -> `Incomparable / PayloadFormatMismatch` ;
+5. payload bytes exactement égaux -> `Exact / ExactCanonicalContent` ;
+6. hash égal mais bytes différents -> `Conflict / ContentHashCollision` ;
+7. seulement ensuite, analyse structurelle du RAW v1 pour une éventuelle preuve de troncature `logMessages` ;
+8. toute autre divergence est `Conflict` ou `Incomparable` sans dominance automatique.
+
+Le `content_hash` reste donc un marqueur d'intégrité/préfiltre, jamais une preuve d'égalité.
+
+## Preuve `logMessages`
+
+La seule dominance automatique admise reste la troncature SVM strictement prouvée.
+
+Pour reconnaître une variante tronquée, toutes les conditions suivantes sont nécessaires :
+
+- les autres composantes top-level sont identiques ;
+- les autres champs `meta` sont identiques ;
+- les deux `logMessages` sont des tableaux de chaînes JSON valides ;
+- le côté tronqué contient exactement un marqueur exact `"Log truncated"` ;
+- ce marqueur est le dernier élément ;
+- le côté complet ne contient aucun marqueur exact ;
+- le préfixe avant le marqueur est byte-identique ;
+- le côté complet possède au moins une ligne au-delà de ce préfixe.
+
+Ainsi :
+
+```text
+canonique complet + entrant tronqué -> CompatibleLessComplete
+canonique tronqué + entrant complet -> CompatibleMoreComplete
+```
+
+Une liste plus courte sans marqueur, un préfixe divergent, un marqueur non exact ou du matériel placé après `"Log truncated"` ne prouve aucune dominance.
+
+## Politique fail-closed des autres champs
+
+Les différences de présence/omission ou `null` contre une valeur concrète ne sont pas transformées en score de qualité. Elles produisent `Incomparable / UnsupportedCanonicalDifference`.
+
+Les valeurs concrètes présentes des deux côtés mais contradictoires produisent `Conflict / CanonicalPayloadConflict`.
+
+Cette politique couvre notamment les champs optionnels documentés dans le plan (`innerInstructions`, `loadedAddresses`, `returnData`, unités consommées, token balances, rewards) sans inventer de hiérarchie de complétude.
+
+## Intégration PostgreSQL
+
+`ksp-store-postgres-lib` ne possède plus l'heuristique privée unidirectionnelle `raw_transaction_incoming_truncated_log_messages_compatible`.
+
+`compare_existing_transaction` appelle désormais directement :
+
+```text
+ksp_store_api::compare_raw_transaction_variants(...)
+```
+
+Comportement de cette tranche :
+
+- `Exact` -> idempotence canonique existante ;
+- `CompatibleLessComplete` -> conservation du canonique et persistance/rattachement de la variante entrante comme en `pre.004` ;
+- `CompatibleMoreComplete` -> relation reconnue mais encore fail-closed côté mutation, car la promotion atomique appartient à `pre.006` ;
+- `Conflict` / `Incomparable` -> conflit PostgreSQL existant, sans ouverture de conflict case durable avant `pre.007`.
+
+Aucune mise à jour du selector, de `canonical_revision` ou de la projection V001 n'est ajoutée ici.
+
+## Canaris
+
+Les tests Store API ajoutés verrouillent :
+
+- la relation bidirectionnelle `LessComplete` / `MoreComplete` ;
+- le marqueur exact, unique et terminal ;
+- le rejet d'une simple liste plus courte ;
+- le rejet d'un préfixe divergent ;
+- le rejet d'un marqueur provider non exact ;
+- le rejet de matériel après le marqueur ;
+- la politique `Incomparable` sur optionalité `null`/valeur ;
+- le `Conflict` sur valeurs concrètes contradictoires ;
+- l'égalité par bytes même si les hashes fournis diffèrent ;
+- la détection d'une collision de hash lorsque les bytes diffèrent.
+
+Les canaris PostgreSQL verrouillent en plus :
+
+- l'usage exclusif du comparateur Store API pour la décision de convergence ;
+- l'absence des anciens helpers privés de compatibilité ;
+- l'absence de promotion/écriture canonique dans `pre.005` ;
+- le refus temporaire de `CompatibleMoreComplete` jusqu'à `pre.006`.
+
+## Hors scope maintenu
+
+Cette tranche n'ajoute pas :
+
+- promotion du selector canonique ;
+- incrément de `canonical_revision` ;
+- remplacement atomique de la projection V001 ;
+- journal de transition canonique ;
+- ouverture de `ksp_raw_transaction_conflicts` ;
+- outcome Worker non terminal pour les conflits ;
+- Store Desk ;
+- retry Store/Transport ;
+- politique de rétention des variantes.
+
+Aucune migration SQL ni ressource V003 n'est modifiée.
+
+## Validation exécutée lors de la génération
+
+Les scripts Python réels du checkout complet sont exécutés sur l'état final puis sur le ZIP rejoué sur une copie fraîche de `pre.004`.
+
+Le toolchain Rust n'est pas disponible dans l'environnement de génération ; les gates Cargo restent opérateur.
+
+## Validation opérateur demandée
+
+```bash
+cargo fmt --all
+cargo fmt --all -- --check
+
+python3 scripts/audit_rust_workspace_rules.py
+python3 scripts/audit_markdown_tables.py README.md RULES.md ROADMAP.md CHANGELOG.md docs prompts crates deltas
+
+cargo check --workspace
+cargo clippy --workspace --all-targets --all-features -- -D warnings
+cargo test -p ksp-store-api --all-targets --all-features
+cargo test -p ksp-store-postgres-lib --all-targets --all-features
+```
+
+## Suite
+
+Après gate propre : `0.3.16-pre.006` — selector canonique et promotion atomique avec revision, projection V001 cohérente, conservation de l'ancien canonique et journal minimal des transitions.
diff --git a/docs/plans/038-V0_3_16_RAW_RESILIENCE_CONFLICT_PLAN.md b/docs/plans/038-V0_3_16_RAW_RESILIENCE_CONFLICT_PLAN.md
index c9a7536..62e345e 100644
--- a/docs/plans/038-V0_3_16_RAW_RESILIENCE_CONFLICT_PLAN.md
+++ b/docs/plans/038-V0_3_16_RAW_RESILIENCE_CONFLICT_PLAN.md
@@ -970,15 +970,15 @@ Contrats Store API backend-neutral : variant identity, relation de qualité, out
 
 #### `0.3.16-pre.003`
 
-Migration V003 : registre d'extension, resources et schéma multi-variantes/selector/conflict minimal ; canaris garantissant l'immuabilité byte/checksum de V000/V001/V002. Implémentation livrée par cette tranche ; gate opérateur requis avant `pre.004`.
+Migration V003 : registre d'extension, resources et schéma multi-variantes/selector/conflict minimal ; canaris garantissant l'immuabilité byte/checksum de V000/V001/V002. Implémentation livrée et gate opérateur confirmé propre après `pre.003-fix.002`.
 
 #### `0.3.16-pre.004`
 
-Backend PostgreSQL : bootstrap V003, variant ledger, rattachement exact des nouvelles observations à leur variante, idempotence et concurrence d'insertion.
+Backend PostgreSQL : bootstrap V003, variant ledger, rattachement exact des nouvelles observations à leur variante, idempotence et concurrence d'insertion. Implémentation livrée et gate opérateur confirmé propre.
 
 #### `0.3.16-pre.005`
 
-Comparateur partagé : `Exact`, `CompatibleLessComplete`, `CompatibleMoreComplete`, `Conflict`, `Incomparable` ; canaris `logMessages` bidirectionnels et politique fail-closed sur les autres champs.
+Comparateur partagé : `Exact`, `CompatibleLessComplete`, `CompatibleMoreComplete`, `Conflict`, `Incomparable` ; canaris `logMessages` bidirectionnels et politique fail-closed sur les autres champs. Implémentation livrée par cette tranche ; gate opérateur requis avant `pre.006`.
 
 #### `0.3.16-pre.006`