diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
new file mode 100644
index 0000000..425d458
--- /dev/null
+++ b/.github/CODEOWNERS
@@ -0,0 +1,11 @@
+# Execution-sensitive paths require maintainer review to prevent unauthorized changes
+# that could affect build integrity, runtime behavior, or asset delivery.
+
+.github/workflows/** @karagozemin
+.vscode/** @karagozemin
+package.json @karagozemin
+pnpm-lock.yaml @karagozemin
+Cargo.toml @karagozemin
+Cargo.lock @karagozemin
+scripts/** @karagozemin
+**/public/fonts/** @karagozemin
\ No newline at end of file
diff --git a/.github/workflows/bindings-check.yml b/.github/workflows/bindings-check.yml
index 3136666..2ddd272 100644
--- a/.github/workflows/bindings-check.yml
+++ b/.github/workflows/bindings-check.yml
@@ -39,7 +39,11 @@ jobs:
       - name: Install stellar CLI
         # 22.8.2 is the latest stable stellar-cli that still supports soroban-sdk 22.
         # CLI 23.0.0 and newer require soroban-sdk 23.
-        run: cargo install stellar-cli --version 22.8.2 --locked
+        # Compile with Rust 1.85.0 (stellar-cli 22.8.2 MSRV) because its locked
+        # ethnum 1.5.0 dependency fails with E0512 on newer stable rustc.
+        run: |
+          rustup toolchain install 1.85.0 --profile minimal
+          RUSTUP_TOOLCHAIN=1.85.0 cargo install stellar-cli --version 22.8.2 --locked
 
       - name: Print Stellar CLI version
         run: stellar --version
diff --git a/apps/web/src/components/PasskeyPanel.tsx b/apps/web/src/components/PasskeyPanel.tsx
index 215d0ca..9a3079a 100644
--- a/apps/web/src/components/PasskeyPanel.tsx
+++ b/apps/web/src/components/PasskeyPanel.tsx
@@ -1,4 +1,4 @@
-import { publicErrorMessage } from "@sub-rosa/logging/errors";
+import { normalizeError, publicErrorMessage } from "@sub-rosa/logging/errors";
 // Copyright (c) 2026 Sub Rosa contributors
 import { useMemo, useState } from "react";
 import { SubRosaClient, validatePasskeySession } from "@sub-rosa/sdk";
@@ -131,8 +131,8 @@ export function PasskeyPanel({
       );
     } catch (e) {
       setStatus("error");
-      const err = e instanceof Error ? e : new Error(String(e));
-      setPanelError(err);
+      const normalized = normalizeError(e);
+      setPanelError(new Error(normalized.message));
       setMessage(publicErrorMessage(e));
     }
   }
@@ -173,8 +173,8 @@ export function PasskeyPanel({
       setMessage(`Smart wallet deployed on testnet: ${created.contractId}`);
     } catch (e) {
       setStatus("error");
-      const err = e instanceof Error ? e : new Error(String(e));
-      setPanelError(err);
+      const normalized = normalizeError(e);
+      setPanelError(new Error(normalized.message));
       const detail = publicErrorMessage(e);
       setMessage(
         `Deploy failed: ${detail}. Try again after refresh; if it persists, sponsor funding on testnet may be missing (Create passkey alone is enough for the demo).`,
@@ -233,10 +233,10 @@ export function PasskeyPanel({
       setMessage("Passkey commit submitted successfully.");
     } catch (e: unknown) {
       setStatus("error");
-      const err = e instanceof Error ? e : new Error(String(e));
-      setPanelError(err);
+      const normalized = normalizeError(e);
+      setPanelError(new Error(normalized.message));
       // Ensure fixture secret seed is kept strictly out of the error message
-      const scrubbed = err.message.replace(/\bS[A-Z2-7]{55}\b/g, "[REDACTED]");
+      const scrubbed = normalized.message.replace(/\bS[A-Z2-7]{55}\b/g, "[REDACTED]");
       setMessage(scrubbed);
     }
   }
diff --git a/apps/web/src/hooks/useTraceHealth.ts b/apps/web/src/hooks/useTraceHealth.ts
index a024ce5..aca1ecf 100644
--- a/apps/web/src/hooks/useTraceHealth.ts
+++ b/apps/web/src/hooks/useTraceHealth.ts
@@ -3,6 +3,7 @@ import { useMemo } from "react";
 import { DEMO_TRACE } from "../demo/trace";
 import { assertDemoTrace } from "../demo/trace-health-check";
 import { verifyMilestones } from "../demo/demo-trace.checksum";
+import { normalizeError } from "@sub-rosa/logging/errors";
 
 export type TraceHealthState =
   | { ok: true }
@@ -24,8 +25,8 @@ export function useTraceHealth(): TraceHealthState {
     try {
       assertDemoTrace(DEMO_TRACE);
     } catch (e) {
-      const message = e instanceof Error ? e.message : String(e);
-      return { ok: false, errorCode: `TRACE_INVALID: ${message}` };
+      const normalized = normalizeError(e);
+      return { ok: false, errorCode: `TRACE_INVALID: ${normalized.message}` };
     }
 
     const phases = (DEMO_TRACE as { lifecycle: Array<{ phase: string }> }).lifecycle.map(
diff --git a/packages/sdk/src/errors.ts b/packages/sdk/src/errors.ts
index 3b44f34..114b0b5 100644
--- a/packages/sdk/src/errors.ts
+++ b/packages/sdk/src/errors.ts
@@ -3,6 +3,80 @@ import type {
   EscrowConservationPhase,
   EscrowConservationReport,
 } from "./conservation.js";
+import { Errors as RoundBindingsErrors } from "@sub-rosa/round-bindings";
+
+export interface RoundContractErrorSpec {
+  code: number;
+  name: string;
+  retryable: boolean;
+}
+
+const RETRYABLE_ERROR_NAMES = new Set([
+  "CommitNotClosed",
+  "RevealNotOpen",
+  "RevealStillOpen",
+  "NotCleared",
+  "NotVoidable",
+]);
+
+function buildRoundContractErrors(): RoundContractErrorSpec[] {
+  return Object.entries(RoundBindingsErrors)
+    .map(([codeStr, info]) => ({
+      code: Number(codeStr),
+      name: info.message,
+      retryable: RETRYABLE_ERROR_NAMES.has(info.message),
+    }))
+    .sort((a, b) => a.code - b.code);
+}
+
+export const ROUND_CONTRACT_ERRORS = buildRoundContractErrors();
+
+export const ROUND_CONTRACT_ERRORS_BY_NAME: Record<string, RoundContractErrorSpec> = Object.fromEntries(
+  ROUND_CONTRACT_ERRORS.map((e) => [e.name, e]),
+);
+
+export function getRoundContractError(key: string | number): RoundContractErrorSpec | undefined {
+  if (typeof key === "number") {
+    return ROUND_CONTRACT_ERRORS.find((e) => e.code === key);
+  }
+  return ROUND_CONTRACT_ERRORS_BY_NAME[key];
+}
+
+export function isRoundContractErrorRetryable(key: string | number | undefined | null): boolean {
+  if (key === undefined || key === null) {
+    return false;
+  }
+  const spec = getRoundContractError(key);
+  return spec?.retryable ?? false;
+}
+
+export function diffContractErrorMapping(
+  contractErrors: { code: number; name: string }[],
+): string[] {
+  const failures: string[] = [];
+  const sdkByCode = new Map(ROUND_CONTRACT_ERRORS.map((e) => [e.code, e]));
+  const sdkByName = ROUND_CONTRACT_ERRORS_BY_NAME;
+
+  for (const { code, name } of contractErrors) {
+    const sdk = sdkByCode.get(code);
+    if (!sdk) {
+      failures.push(`code ${code} (${name}) not mapped in SDK`);
+      continue;
+    }
+    if (sdk.name !== name) {
+      failures.push(`code ${code}: SDK has ${sdk.name}, contract has ${name}`);
+    }
+  }
+
+  for (const sdk of ROUND_CONTRACT_ERRORS) {
+    const found = contractErrors.some((e) => e.code === sdk.code);
+    if (!found) {
+      failures.push(`SDK error ${sdk.name} (#${sdk.code}) missing from contract errors list`);
+    }
+  }
+
+  return failures;
+}
 
 export class SubRosaClientConfigError extends Error {
   readonly name = "SubRosaClientConfigError";
diff --git a/scripts/check-env-examples.mjs b/scripts/check-env-examples.mjs
index e227bc9..69b154e 100644
--- a/scripts/check-env-examples.mjs
+++ b/scripts/check-env-examples.mjs
@@ -2,6 +2,9 @@
 import { readFileSync } from 'node:fs';
 import { fileURLToPath } from 'node:url';
 import { resolve } from 'node:path';
+import { createLogger } from '../packages/logging/src/index.cjs';
+
+const diagnostics = createLogger('scripts.check-env-examples');
 
 const TEMPLATES = [
   ['.env.example', new URL('../.env.example', import.meta.url)],
@@ -61,7 +64,7 @@ export function checkTemplates(templates = TEMPLATES) {
 
 if (process.argv[1] && resolve(process.argv[1]) === fileURLToPath(import.meta.url)) {
   const errors = checkTemplates();
-  for (const error of errors) console.error(error);
+  for (const error of errors) diagnostics.error('invalid-template', error);
   if (errors.length) process.exitCode = 1;
-  else console.log('Environment templates are valid.');
+  else diagnostics.info('valid-templates', 'Environment templates are valid.');
 }