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27 lessons in this view
READ → EXPERIMENT → EXPLAIN- 01
Building a Learning System That Actually Sticks
Research-informed retrieval and spacing with a broad curriculum, honest schedule arithmetic, bounded review queues and no invented automation or mastery promises.
30 min read - 02
R01 · Week 1 Recall & Drill
Week 1 revision: reproducible dev environments, Git's object model, shell pipelines, doc-hunting strategy, and Python's reference-based memory model.
20 min read - 03
R02 · Week 2 Recall & Drill
Week 2 revision: the iterator protocol behind for-loops, argument grammar and closures, data structure Big-O choices, class attribute lookup, and inheritance vs composition.
20 min read - 04
R03 · Week 3 Recall & Drill
Week 3 revision: exception discipline and pdb, import resolution and packaging, pytest fixtures and the TDD loop, type hints that no runtime enforces, and Big-O as a growth rate.
20 min read - 05
R04 · Week 4 Recall & Drill
Week 4 revision: discrete math as the language under SQL, vectors and cosine similarity, matrices as transformations, the chain rule, and gradient descent from scratch.
20 min read - 06
R05 · Week 5 Recall & Drill
Week 5 revision: distributions and Bayes' rule, what a p-value actually claims, two-pointer and sliding-window templates, hashmap internals, and linked-list surgeries.
20 min read - 07
R06 · Week 6 Recall & Drill
Week 6 revision: LIFO vs FIFO as a scheduling choice, recursion's three ingredients, tree traversal orders, heaps as partial order, and graph traversal with weights.
20 min read - 08
R07 · Week 7 Recall & Drill
Week 7 revision: sort trade-offs beyond Big-O, the two binary search templates, DP preconditions versus caching, greedy proofs and backtracking pruning, and normalisation to 3NF.
20 min read - 09
R08 · Week 8 Recall & Drill
Week 8 revision: SQL logical execution order, joins as filtered Cartesian products, aggregate NULL semantics, windows that preserve rows, and recursive CTEs.
20 min read - 10
R09 · Week 9 Recall & Drill
Week 9 revision: B-tree selectivity and composite index order, isolation levels and write skew, reading execution plans, the four NoSQL families, and star schema grain.
20 min read - 11
R10 · Week 10 Recall & Drill
Week 10 revision: bounded versus unbounded data, Spark stages and shuffles, Kafka as a log rather than a queue, watermarks and exactly-once effect, and idempotent orchestration.
20 min read - 12
R11 · Week 11 Recall & Drill
Week 11 revision: dbt as a compiler not an engine, lakehouse metadata layers over Parquet, the four data-quality pillars, lineage-driven governance and cost, and HTTP caching.
20 min read - 13
R12 · Week 12 Recall & Drill
Week 12 revision: resource modelling and idempotency keys, GraphQL's N+1 and cost limits, Protobuf field tags and RPC shapes, delegated authorisation versus identity, and Linux processes, memory, and file descriptors.
20 min read - 14
R13 · Week 13 Recall & Drill
Week 13 revision: TCP as a byte stream, L4 versus L7 load balancing, cache-aside and stampedes, CDN cache keys and Vary, and Docker layers as processes not VMs.
20 min read - 15
R14 · Week 14 Recall & Drill
Week 14 revision: declarative reconciliation over imperative starts, config and secrets injection, cloud identity and network isolation, Terraform state as authoritative mapping, and CAP versus PACELC.
20 min read - 16
R15 · Week 15 Recall & Drill
Week 15 revision: replication topologies and split-brain, consistency guarantees and their scope, Raft's real difficulty, hot partitions and consistent hashing, and at-least-once queues.
20 min read - 17
R16 · Week 16 Recall & Drill
Week 16 revision: RTO and RPO driving topology, which observability pillar answers which question, PromQL and cardinality, error budgets as budgets, and mitigate-before-diagnose.
20 min read - 18
R17 · Week 17 Recall & Drill
Week 17 revision: resource authorization, password KDFs, certificate trust and SAN checks, SQL injection boundaries, leakage-safe evaluation and least-squares gradients.
40 min read - 19
R18 · Week 18 Recall & Drill
Week 18 revision: likelihood and decision costs, ridge/lasso geometry, learning-curve assumptions, greedy tree impurity and measured ensemble diversity.
40 min read - 20
R19 · Week 19 Recall & Drill
Week 19 revision: negative-gradient boosting, tie-aware ranking metrics, leakage-free preprocessing, imbalance policies and honest evaluation of selected procedures.
40 min read - 21
R20 · Week 20 Recall & Drill
Week 20 revision: affine collapse and nonlinear XOR, batched MLP shapes, numerical backprop checks, optimizer recurrences and PyTorch mode/gradient contracts.
40 min read - 22
R21 · Week 21 Recall & Drill
Week 21 revision: dropout and normalization contracts, convolution shapes, recurrent Jacobian products, embedding objectives and controlled transfer-learning decisions.
40 min read - 23
R22 · Week 22 Recall & Drill
Week 22 revision: exact toy BPE, attention variance and tensor shapes, permutation equivariance, positional mechanisms and fixed-width versus KV-cache budgets.
40 min read - 24
R23 · Week 23 Recall & Drill
Week 23 revision: transformer block contracts, attention visibility, normalized decoding filters, conditional compute heuristics and exact streamed attention.
40 min read - 25
R24 · Week 24 Recall & Drill
Week 24 revision: prompting evaluation, chunk-span recovery, authorized hybrid ranking, exact-neighbor recall and bounded verified tool-workflow models.
40 min read - 26
R25 · Week 25 Recall & Drill
Worked revision of agent handoffs, judge bias, LoRA, KV-cache sizing, batching and multimodal extraction with bounded local code and source-backed answers.
38 min read - 27
R26 · Week 26 Recall & Drill
Worked system-design revision: explicit capacity assumptions, atomic identifier allocation, lost acknowledgements, feed work and enforced AI cost budgets.
38 min read