diff --git a/src/config/configuration.spec.ts b/src/config/configuration.spec.ts
new file mode 100644
index 00000000..d5e459fd
--- /dev/null
+++ b/src/config/configuration.spec.ts
@@ -0,0 +1,58 @@
+import configuration from './configuration';
+
+describe('configuration (#601)', () => {
+  const ORIG = process.env;
+  beforeEach(() => {
+    process.env = { ...ORIG };
+  });
+  afterAll(() => {
+    process.env = ORIG;
+  });
+
+  it('uses dev defaults when env is unset', () => {
+    delete process.env.NODE_ENV;
+    delete process.env.PORT;
+    const cfg = configuration();
+    expect(cfg.env).toBe('development');
+    expect(cfg.jwt.secret).toBe('insecure-dev-secret');
+    expect(cfg.stellar.network).toBe('testnet');
+  });
+
+  it('parses integer env vars', () => {
+    process.env.PORT = '9000';
+    process.env.ESCROW_DEADLINE_SECONDS = '3600';
+    const cfg = configuration();
+    expect(cfg.port).toBe(9000);
+    expect(cfg.stellar.escrowDeadlineSeconds).toBe(3600);
+  });
+
+  it('parses boolean env vars strictly (=== "true")', () => {
+    process.env.DATABASE_SYNCHRONIZE = 'true';
+    process.env.DATABASE_LOGGING = 'false';
+    const cfg = configuration();
+    expect(cfg.database.synchronize).toBe(true);
+    expect(cfg.database.logging).toBe(false);
+  });
+
+  it('falls back MAINTENANCE_POOL_CONTRACT_ID to ESCROW_CONTRACT_ID', () => {
+    delete process.env.MAINTENANCE_POOL_CONTRACT_ID;
+    process.env.ESCROW_CONTRACT_ID = 'escrow-abc';
+    expect(configuration().stellar.maintenancePoolContractId).toBe(
+      'escrow-abc',
+    );
+  });
+
+  it('prefers MAINTENANCE_POOL_CONTRACT_ID over the escrow fallback', () => {
+    process.env.MAINTENANCE_POOL_CONTRACT_ID = 'pool-xyz';
+    process.env.ESCROW_CONTRACT_ID = 'escrow-abc';
+    expect(configuration().stellar.maintenancePoolContractId).toBe('pool-xyz');
+  });
+
+  it('reads the per-asset contract ids', () => {
+    process.env.USDC_TOKEN_CONTRACT_ID = 'usdc-1';
+    process.env.XLM_TOKEN_CONTRACT_ID = 'xlm-1';
+    const cfg = configuration();
+    expect(cfg.stellar.assetContractIds.USDC).toBe('usdc-1');
+    expect(cfg.stellar.assetContractIds.XLM).toBe('xlm-1');
+  });
+});
diff --git a/src/config/configuration.ts b/src/config/configuration.ts
index 40e91db2..b7fca6bd 100644
--- a/src/config/configuration.ts
+++ b/src/config/configuration.ts
@@ -67,9 +67,32 @@ export interface AppConfig {
   };
 }
 
+/**
+ * Parse a numeric env var, failing loudly at config-load if it isn't a
+ * positive integer. A bare `parseInt` returns NaN on garbage input — for
+ * ESCROW_DEADLINE_SECONDS that NaN reached `resolveDeadline` and threw
+ * `RangeError: cannot convert NaN to BigInt` on every escrow fund, after the
+ * PENDING row was already saved (#610). Validate here so a bad value is a
+ * boot-time config error, not a mid-transaction crash.
+ */
+function envInt(
+  name: string,
+  raw: string | undefined,
+  fallback: number,
+): number {
+  const v =
+    raw === undefined || raw === '' ? fallback : Number.parseInt(raw, 10);
+  if (!Number.isFinite(v) || v <= 0) {
+    throw new Error(
+      `Invalid ${name}: expected a positive integer, got '${raw}'`,
+    );
+  }
+  return v;
+}
+
 export default (): AppConfig => ({
   env: process.env.NODE_ENV ?? 'development',
-  port: parseInt(process.env.PORT ?? '3000', 10),
+  port: envInt('PORT', process.env.PORT, 3000),
   appUrl: process.env.APP_URL ?? 'http://localhost:3000',
   frontendUrl: process.env.FRONTEND_URL ?? 'http://localhost:3001',
   logLevel: process.env.LOG_LEVEL ?? 'debug',
@@ -96,9 +119,10 @@ export default (): AppConfig => ({
   },
 
   analytics: {
-    platformSummaryTtlMs: parseInt(
-      process.env.ANALYTICS_PLATFORM_SUMMARY_TTL_MS ?? '60000',
-      10,
+    platformSummaryTtlMs: envInt(
+      'ANALYTICS_PLATFORM_SUMMARY_TTL_MS',
+      process.env.ANALYTICS_PLATFORM_SUMMARY_TTL_MS,
+      60000,
     ),
   },
   stellar: {
@@ -118,9 +142,10 @@ export default (): AppConfig => ({
       USDC: process.env.USDC_TOKEN_CONTRACT_ID ?? '',
       XLM: process.env.XLM_TOKEN_CONTRACT_ID ?? '',
     },
-    escrowDeadlineSeconds: parseInt(
-      process.env.ESCROW_DEADLINE_SECONDS ?? '7776000',
-      10,
+    escrowDeadlineSeconds: envInt(
+      'ESCROW_DEADLINE_SECONDS',
+      process.env.ESCROW_DEADLINE_SECONDS,
+      7776000,
     ),
   },
 });
diff --git a/src/escrow/escrow.service.ts b/src/escrow/escrow.service.ts
index 6d2dd289..c252993f 100644
--- a/src/escrow/escrow.service.ts
+++ b/src/escrow/escrow.service.ts
@@ -584,20 +584,14 @@ export class EscrowService {
     recipients: Array<[string, number]>,
     manager?: EntityManager,
   ): Promise<ContractInvocationResult> {
-    return this.invokeOnLockedEscrow(escrow, operation, () =>
-      this.soroban.invoke(
-        'release',
-        // `release(issue_id: u64, recipients)` — u64-typed on-chain (#301).
-        [u64(this.onChainKeyFor(escrow)), recipients],
-        this.contractOpts(escrow),
-      ),
     return this.invokeOnLockedEscrow(
       escrow,
       operation,
       () =>
         this.soroban.invoke(
           'release',
-          [this.onChainKeyFor(escrow), recipients],
+          // `release(issue_id: u64, recipients)` — u64-typed on-chain (#301).
+          [u64(this.onChainKeyFor(escrow)), recipients],
           this.contractOpts(escrow),
         ),
       manager,
diff --git a/src/github/github-webhooks.service.spec.ts b/src/github/github-webhooks.service.spec.ts
index 45bb6fe8..a35ac3be 100644
--- a/src/github/github-webhooks.service.spec.ts
+++ b/src/github/github-webhooks.service.spec.ts
@@ -869,6 +869,9 @@ describe('GithubWebhooksService', () => {
 
       expect(bountiesService.markInReview).not.toHaveBeenCalled();
       expect(bountiesService.markMergedAndRelease).not.toHaveBeenCalled();
+    });
+  });
+
   // #308: a redelivered X-GitHub-Delivery used to hit the unique constraint
   // on webhook_events.deliveryId and escape handleEvent as a 500, so every
   // redelivery of that event failed forever.
diff --git a/src/sponsors/sponsors.controller.ts b/src/sponsors/sponsors.controller.ts
index b7a48cca..c097bf1e 100644
--- a/src/sponsors/sponsors.controller.ts
+++ b/src/sponsors/sponsors.controller.ts
@@ -26,25 +26,6 @@ function validatePage(limit?: number, offset?: number) {
     throw new BadRequestException('offset must be >= 0');
   }
   return { limit, offset };
-/**
- * Parse optional limit/offset query params, rejecting NaN, negatives,
- * non-integers, and limits above MAX_PAGE_LIMIT with a 400 (#280).
- */
-function parsePagination(limit?: string, offset?: string) {
-  const parse = (name: string, raw: string | undefined, min: number, max: number) => {
-    if (raw === undefined || raw === '') return undefined;
-    const n = Number(raw);
-    if (!Number.isInteger(n) || n < min || n > max) {
-      throw new BadRequestException(
-        `${name} must be an integer between ${min} and ${max}`,
-      );
-    }
-    return n;
-  };
-  return {
-    limit: parse('limit', limit, 1, MAX_PAGE_LIMIT),
-    offset: parse('offset', offset, 0, Number.MAX_SAFE_INTEGER),
-  };
 }
 
 @ApiTags('sponsors')
@@ -73,7 +54,6 @@ export class SponsorsController {
   ) {
     this.assertOwnsSponsor(user, id);
     return this.sponsorsService.dashboard(id, validatePage(limit, offset));
-    return this.sponsorsService.dashboard(id, parsePagination(limit, offset));
   }
 
   @ApiBearerAuth()
@@ -91,6 +71,5 @@ export class SponsorsController {
       id,
       validatePage(limit, offset),
     );
-    return this.sponsorsService.milestoneProgress(id, parsePagination(limit, offset));
   }
 }