Custom Smart Card Development Services

We design, develop, and deploy custom applications on NXP JCOP 4.5 P71 secure elements — from standard JavaCard applets to exotic cryptographic implementations via NXP SecureBox native C.

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What We Build on NXP JCOP 4.5 P71 Secure Elements

The NXP JCOP 4.5 P71 is the most advanced commercially available secure element, combining a JavaCard virtual machine with NXP’s SecureBox coprocessor for native C execution. It is the hardware platform behind Cryptnox’s own product line and the foundation of every custom development engagement we undertake.

Our engineering team has shipped production firmware for blockchain hardware wallets, enterprise authentication tokens, government-grade identity cards, and IoT security modules — all on the JCOP P71. We bring this deep, hands-on expertise to every client project, whether you need a straightforward payment applet or a completely novel cryptographic primitive that does not exist anywhere else in the smart card ecosystem.

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Development Capabilities Across Three Layers

The JCOP P71 exposes three distinct programming surfaces. Cryptnox has mastered all three,
enabling us to meet requirements that are impossible to fulfill on any other smart card platform.

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Layer 1

JavaCard Applet Development

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Layer 2

NXP SecureBox Native C

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Layer 3

Full-Stack Integration

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Proven SecureBox Expertise: Three Flagship Projects

These are not proofs-of-concept. Each project shipped to production hardware, passed
comprehensive test vectors, and enabled real transactions on live networks.

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Exotic Hash Functions on Secure Elements

Algorithm

Output

Use Case

#E2F5FF

32 bytes

Ethereum

BLAKE2b-512

64 bytes

Zcash

BLAKE2s-256

32 bytes

Zcash / Filecoin

Poseidon- Stark252

32 bytes

StarkNet

Poseidon-Mina

32 bytes

Mina Protocol

RedDSA / Pallas

Zcash Orchard Shielded Transaction Signing

256ms

Signing time per operation

3.8

Signatures per second throughput

100×

Stress test signatures — all passed

BLS12-381

Ethereum 2.0 and Multi-Chain BLS Signatures

1.8s

Fastest signing path achieved

45%

Performance improvement over
baseline

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Constant-time execution — timing-safe

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Industries and Use Cases We Serve

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Blockchain & Cryptocurrency

Custom hardware wallets for any blockchain protocol, including exotic curve and hash support unavailable in off-the-shelf products.

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Financial Services & Payments

Payment applets, banking tokens, and the Card Wallet as a Service (C-WAAS) platform for financial-grade transaction security.

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Digital Identity & Government

ePassports, government credentials, and high-assurance identity documents on CC EAL6+ certified hardware.

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Enterprise Authentication

Custom FIDO2 security keys, corporate badge systems, and multi-application smart cards for enterprise identity programs.

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IoT Device Security

Embedded secure element integration, device attestation, and secure firmware delivery for connected hardware platforms.

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Why Enterprises Choose Cryptnox

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Swiss Engineering and Jurisdiction

Headquartered in Geneva, Switzerland — one of the world’s strongest data protection and IP frameworks. Your project is protected by Swiss law from day one.

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Deep NXP Partnership

As an NXP partner with access to SecureBox tooling and documentation, we deliver cryptographic capability far beyond what is possible in the standard JavaCard environment.

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Proven Production Deployments

Every methodology we apply has been validated in real Cryptnox products that ship to thousands of customers worldwide on the JCOP P71 platform.

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Patent Portfolio

Cryptnox holds granted and pending patents in the US, Europe, and China — a foundation of original innovation that underpins every engagement. View patent portfolio →

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The Development Process from Concept to Production

A structured five-phase process ensures your project is delivered securely, on schedule, and with
full IP ownership transferred to you at completion. Hover each phase to expand details.

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Requirements Analysis &
Feasibility

We work with your team to capture cryptographic, performance, form-factor, and certification requirements. We assess feasibility on JCOP P71 and identify any constraints before any code is written.

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Architecture & 
Prototype

We select the optimal development layer — JavaCard, SecureBox native C, or a hybrid — and deliver a working prototype with benchmarks for your review and approval.

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Security Hardening &
Optimization

Side-channel mitigations, fault injection defenses, constant-time execution, and performance tuning are applied at this phase to meet production security standards.

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Integration & 
Testing


Applet and host-side integration are completed together. We run comprehensive test vectors, interoperability testing, and stress tests before sign-off.

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Production Deployment & Support

We support your manufacturing partner during initial card personalization and provide post-launch engineering support under an agreed SLA.

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Frequently Asked Questions

What types of custom applets can you develop on the JCOP 4.5 P71?

We develop the full range of smart-card applications: standard JavaCard 3.1 applets (PKI, signing, key management, GlobalPlatform secure channels), payment and banking applets, FIDO2/WebAuthn implementations, multi-application identity cards, and advanced NXP SecureBox native C implementations for non-standard cryptography — custom elliptic curves, exotic hash functions, and novel signature schemes such as RedDSA/Pallas, BLS12-381, and Poseidon.

What is NXP SecureBox and why does it matter for my project?

NXP SecureBox is a native C execution environment that runs alongside the JavaCard VM on the JCOP P71. It lets us implement cryptography that JavaCard’s high-level API cannot express — exotic curves, custom hash functions, and signature schemes outside the standard library — while still using the FAME3 cryptographic coprocessor that powers the certified JavaCard primitives. SecureBox is the only path to hardware-rooted signing for blockchain protocols that rely on non-standard cryptography (Zcash Orchard, Ethereum 2.0 BLS, Mina, StarkNet) without sacrificing the secure element’s tamper-resistance.

How long does a typical custom development project take from kickoff to production?

A full engagement typically runs 6–12 months. Architecture and prototype: 2–3 months. Applet development and on-card integration: 3–6 months. Host-side integration (mobile/desktop SDK, backend) and benchmarking: 1–2 months. Card personalization and production rollout: 1–2 months. If Common Criteria evaluation is required, add 6–12 months for the certification lab on top.

Who owns the intellectual property developed during the engagement?

Custom applet code, business logic, and project-specific integrations are owned by the client. Cryptnox retains rights to its pre-existing libraries, SecureBox utilities, and host-side SDKs that are reused across projects. Specific IP terms — including exclusivity, source-code escrow, and rights to derivative works — are negotiated per engagement and captured in the Master Services Agreement.

What is the minimum order quantity for custom smart card production?

For the development phase we supply 50–100 prototype cards for engineering and integration testing. For production, MOQs typically start at 1,000–5,000 cards depending on the chip variant and personalization complexity. We can advise on volume pricing once the bill of materials and personalization profile are defined.

Can Cryptnox integrate the smart card with our existing mobile app or enterprise platform?

Yes. We deliver host-side SDKs for iOS (Core NFC), Android (NFC and USB OTG via the Cryptnox Wallet app), and Windows/macOS/Linux desktop middleware (PC/SC), along with REST and GraphQL backend services. We have shipped integrations against Microsoft Entra ID, Okta, custom KMS/HSM stacks, and bespoke enterprise platforms — integration with your existing IAM is part of the standard engagement scope.

Does Cryptnox support Common Criteria or FIPS certification for custom projects?

The JCOP 4.5 P71 base platform is Common Criteria EAL6+ certified by NXP. For custom applets we support composite evaluation (typically CC EAL4+ on top of the EAL6+ base) and FIPS 140-3 validation. Cryptnox provides design documentation, security policy, test vectors, and engineering support for the certification lab; the client funds the lab fees.

Contact Our Engineering Team.

Tell us about your custom smart card development project.

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Continue Exploring Our Smart Card Development Services

NXP JCOP P71 secure element integration for IoT, payments, identity, and blockchain. Learn more →

JavaCard 3.1 applet development, JCOP 4.5 extensions, GlobalPlatform integration. Learn more →

White-label hardware wallet cards for any blockchain protocol — including non-standard cryptography. Learn more →

Card-form-factor FIDO2 keys for enterprise authentication and passkey deployments. Learn more →

Dual-interface NFC smart cards for access, identity, supply chain and multi-application use cases. Learn more →

Real-world SecureBox / JavaCard projects on NXP JCOP P71 — verified on production hardware. Learn more →