Cryptography Engineer — Post-Quantum & Secure Implementation

QNu Labs · Bangalore · In person
Before you apply
This is an early-career role (0–2 years) and an in-person one in Bangalore. We only review applications that include a link to cryptographic code you have written yourself. If you have not implemented a primitive or protocol from a specification, this is not the right role for you yet. This is not a firmware, SOC, VAPT or full-stack position.
About QNu Labs
QNu Labs is India's first and only quantum security technology company, building quantum-safe solutions that protect mission-critical data. Headquartered in Bangalore, we are backed by the National Quantum Mission under the Department of Science & Technology, Government of India.
Our patent-backed products — Armos, Tropos, QHSM and the QShield™ platform built on NIST-compliant post-quantum cryptography — are TEC-certified and deployed across the Indian Army, Navy, the public sector and global enterprises.
The role
You will take cryptographic schemes from specification to shipped product: implementing them, proving them correct, making them fast, and making them resistant to attacks that target the implementation rather than the mathematics.
The role sits in our Center of Excellence for Advanced Crypto Secure Systems, which works on problems where cryptography creates a capability conventional cybersecurity cannot.
What you'll do
Implement primitives and protocols in C and Python, working from NIST PQC specifications, standards and papers
Write constant-time code and harden implementations against side-channel and fault attacks
Validate against test vectors and write the negative tests that catch the failures that matter
Benchmark schemes across parameter sets and report numbers others can reproduce
Take those implementations down to constrained targets, where key sizes and cycle counts actually bite
Essential
You have implemented a cryptographic primitive or protocol yourself, from a specification, without leaning on a high-level library — and can show us the code
Strong C or Python
The mathematics to read a scheme rather than just its pseudocode: number theory, abstract algebra, probability
Familiarity with lattice-based constructions and the NIST PQC standards, or the background to get there quickly
Data structures and algorithms, with real reasoning about complexity and memory
What you'll learn here
You do not need to arrive with hardware experience. We will teach you embedded development, hardware bring-up, side-channel measurement and countermeasure design on the job.
Bonus
Zero-knowledge proofs, elliptic-curve cryptography
Contributions to open-source crypto (liboqs, PQClean, OpenSSL or similar)
CTF crypto categories, Cryptopals, or published cryptanalysis
Embedded systems, OS internals, ARM
Qualifications
Bachelor's or Master's in mathematics, computer science, or a related field. Thesis work, internships and independent projects count as much as employment history.

Work arrangement
No