Security Engineer

Start from zero and build a solid Python foundation. You will learn variables, data types, conditionals, loops, and string manipulation through hands-on exercises with real code execution.

Go beyond the basics. Master lists, dictionaries, functions, and file handling through practical exercises that mirror real-world programming tasks.

Learn Go: the language behind Docker, Kubernetes, and most of modern infrastructure. Static types, fast compiles, no class hierarchies. Every lesson is hands-on with real go run execution.

Level up from Go Fundamentals. Interfaces, error handling patterns, goroutines, channels, select, defer/panic/recover. The features that make Go unique — and how real Go services use them.

Beyond Go Intermediate. Context cancellation, sync primitives in depth, generics (1.18+), reflection, unsafe. The features Go services running at scale actually use.

Implement a cryptographic random number generator. Learn why Math.random() and rand() are insecure, how the OS gathers entropy, and implement HMAC-DRBG (NIST SP 800-90A) and Fortuna. The foundation underneath every TLS handshake, every AES IV, every session token.

Implement secure password hashing: salts, PBKDF2-style iteration, bcrypt, argon2id, constant-time comparison, and rehash-on-login. Why SHA/MD5 for passwords is dangerous and what to use instead.

Implement SHA-256 from raw bit operations. You'll build ROTR/Σ/σ/Ch/Maj, the message schedule, the 64-round compression function, padding, and the full Merkle-Damgård construction. Then add HMAC for message authentication. By the end you'll deeply understand the hash function used in Bitcoin, Git, TLS, and JWT.

Implement the AES block cipher from raw bit operations: state matrix, GF(2^8) arithmetic, the S-box, ShiftRows, MixColumns, key schedule, and full 10-round encryption. Then add modes of operation (ECB, CBC, CTR, GCM). The cipher behind TLS, WPA2, and disk encryption.

Implement RSA from number theory primitives: modular exponentiation, prime generation via Miller-Rabin, modular inverse via extended Euclidean, key generation, encrypt/decrypt, signatures, padding (PKCS#1, OAEP, PSS). Then learn the historical attacks. The asymmetric crypto algorithm behind TLS, PGP, SSH, and Bitcoin until 2024.

Build elliptic-curve signatures from scratch: modular arithmetic, finite fields, point addition on secp256k1, scalar multiplication, ECDSA sign/verify. Foundation of Bitcoin, Ethereum, TLS. Includes the famous nonce-reuse attack that broke the PS3.

Build TLS 1.3 from scratch: AEAD ciphers, HKDF key schedule, ephemeral X25519 key exchange, the 1-RTT handshake, encrypted record layer, session resumption with PSK, and 0-RTT data. The protocol securing every HTTPS request on the modern internet.

Build a working CA: parse X.509 / ASN.1 DER, accept CSRs, validate domain ownership, issue certificates with proper extensions, publish to Certificate Transparency logs, manage revocation via CRL/OCSP, and protect signing keys in HSMs. The infrastructure underlying every HTTPS connection.

Build end-to-end encryption like Signal/WhatsApp: X3DH for asynchronous key agreement, the Double Ratchet for forward secrecy + break-in recovery, sender keys for group chat, and metadata-privacy techniques. The protocol behind 2 billion encrypted conversations daily.

Implement JWT (JSON Web Tokens) end-to-end: base64url encoding, signing with HS256/RS256, claim validation, key rotation via kid, and defenses against the well-known JWT attacks (alg=none, key confusion, weak secrets). Used by every modern auth system.

Implement an OAuth 2.0 authorization server: authorization code flow, PKCE for public clients, access + refresh tokens with rotation, scopes, redirect URI validation, state-based CSRF defense, and token introspection. The auth protocol behind 'Login with Google/GitHub/Facebook' and every B2B SaaS.