Atlas
models
- Mixture of Experts
Sparse capacity, routing, auxiliary and loss-free balancing, expert layouts, training stability, and their systems constraints—in one topic.
- Attention
From a masked weighted average to head sharing, latent caches, recurrent memory and IO-aware kernels. Separate what each method changes.
- Tokenization and Input Representations
From ordered BPE merges to probabilistic segmentation, dynamic byte patches and sentence-level concepts: what each unit preserves and costs.
- Positional Encodings
Sinusoidal scales, relative RoPE geometry, context extension, NoPE hybrids and translation generators—with cache and stability conditions.
- Transformer Architecture
Follow the residual stream through attention, gated feedforward layers, normalization, depth retrieval and the vocabulary head; connect shape, expressivity and activation memory.
- Recurrent and Looped Models
Follow a state through gates, repeated blocks, early exit, aligned updates, recirculated caches and full-bandwidth latent feedback; separate parameter reuse from compute savings.
- Small and On-Device Model Recipes
Connect small-model capacity, repeated depth, training investment and hardware-aware deployment without confusing their budgets.
- Structured Decision and Safety Models
Use question-conditioned classifiers as bounded software components, distinguish probability summaries from calibration, and learn policy boundaries through content-preserving contrasts.
- Diffusion and Score-Based Generation
Connect Gaussian corruption, posterior denoising, scores and reverse dynamics; distinguish solver acceleration, trajectory consistency and generator distribution matching.
- Learning, Abduction, and Scientific Discovery
Separate finding a solution from choosing its premises; connect scientific invention, interventions and tests without treating a position paper as an impossibility theorem.
- Detection and Spatial Predictions
Connect box geometry, score ordering, greedy suppression and fusion; inspect crowded-scene failures and keep inference thresholds separate from evaluation.
- Self-Supervised Vision Learning
Connect global and patch targets, online teachers, masked versus all-token supervision, collapse prevention and Gaussian projection tests; choose evidence for the intended backbone use.
math
- Information Theory and Compression
Entropy is the baseline coding cost. KL is the mismatch cost. Connect these quantities to prediction, language models and compression-based similarity.
- Vectors and Geometry
Magnitude, unit embeddings, loss/penalty distinctions, dot versus cross products, orientation and the limits of normalization.
- Probability and Distributions
Conditioning, total probability, joint dependence, CDFs and quantiles, characteristic functions and their moment/test connections.
- Differentiation and Optimization Geometry
Partial, product and chain rules become accumulated backpropagation; gradients, curvature, stationary points and random-landscape assumptions answer different questions.
- Statistics and Evaluation
Online estimates, sampling uncertainty, CLT conditions, hypothesis-test power, A/B impact and leakage-aware cross-validation.
- Mathematical Problem Solving
Model hidden states, probability and guarantees before choosing counting, expectation, arrival processes, information bounds, invariants or rates.
training
- Losses and Objectives
Choose what the model should estimate. Connect residual losses, probability scores, logit gradients, sparse output maps, margins and reduction rules.
- Distributed Training and Parallelism
Split examples, state, tensors, context, layers or experts. Follow ownership, exact partial results and the communication needed to assemble them.
- Optimization
Connect gradient estimates to momentum, AdamW, matrix-aware Muon, batch noise, schedules and hyperparameter transfer; use exact examples rather than universal tuning rules.
- Scaling Laws
Allocate parameters, data and compute; distinguish empirical frontiers, repetition, deployment objectives and coupled loss surfaces.
- Training Data
Design a sampling policy: collection and quality, duplicate ownership, token and target mass, repetition caps, mixture search and source-conditioned curricula.
- Training Stability and Generalization
Diagnose loss regimes and gradient flow, clip with the correct contract, resume the complete run, and choose checkpoints using shortcut resistance and measured transfer.
- Pretraining: Experiments and Run Design
Turn a capability objective into controlled ablations, a frozen recipe, a feasible token budget and a recoverable full-scale run.
- Precision and Quantization
Connect formats, scaling, attention error and quantization-aware training to the actual arithmetic and memory contract.
- Frontier Model Training Recipes
Compare complete model-building recipes without confusing parameter capacity, training exposure, rollout scale and agent-system results.
- Collective Communication
Visualize who sends, who receives, and who owns the result. Broadcast, Reduce, AllReduce, AllGather, ReduceScatter, AllToAll and point-to-point exchanges, with distributed training examples.
execution
- Speculative Decoding
Exact accept/correct sampling, chain and tree verification, MTP/EAGLE/DFlash/DSpark, cache rollback and confidence-aware serving.
- Decoding and Sampling
Temperature, support truncation, recurrent-state guidance and keyed watermark sampling change how model predictions become tokens.
- GPU Infrastructure
Follow the electrical and heat paths that make GPU capacity usable: branch placement, isolated cooling loops, failure domains and productive GPU-hours.
- Profiling and Kernel Optimization
Connect framework operations to launches and GPU work; test critical-path hypotheses with bounded traces, controlled changes and measurements outside the profiler.
- Compute, Memory, and Performance
Count the model work and bytes, match the relevant hardware ceilings, and connect healthy-step efficiency to memory, scaling, committed progress and cost.
- GPU Communication
Follow collective results through schedules, channels, transports and readiness protocols. Understand small-message latency, push/pull, safe buffer reuse and NCCL implementation tradeoffs.
- Serving Models
Connect latency to prefill, decode, KV state, batching, prefix reuse, sharding and disaggregation. Separate resource estimates from measured goodput.
- GPU Architecture and CUDA Programming
Trace a CUDA thread to its output, follow warp addresses into memory sectors, drain shared-memory bank queues, reuse matrix tiles, fold reductions and overlap copies with two buffers.
algorithms
- Arrays and Hashing
Choose stored state: membership, counts, complements, canonical keys, prefix and suffix products.
- Pointers and Sliding Windows
Prove boundary movement: sorted pairs, compaction, center expansion, fixed and variable windows, requirement counts and signed-sum failures.
- Stacks and Monotonic Structures
Unresolved work, delimiter nesting, simulation, postfix operands, next-greater candidates and amortized push/pop reasoning.
- Binary and Monotonic Search
Exact search, first-true boundaries, answer-space feasibility and transformed order with explicit interval contracts.
- Linked Lists and Pointer Ownership
Preserve reachability while rewiring: dummy nodes, reversal, fast/slow traversal, merges, phase boundaries and node identity.
- Graph Algorithms
Choose the representation and objective: reachability, distances, dependencies, connectivity, spanning trees or every-edge routes.
- Trees and Prefix Structures
Subtree returns and ancestor state, DFS/BFS orders, BST bounds, ancestors, tries, terminals and shared-prefix pruning.
- Dynamic Programming
Define sufficient state, recurrence, base cases and dependency order; connect 1D/2D, knapsack, alignment and safe rolling memory.
- Backtracking and Search
Explore decisions with owned branch state: combinations, permutations, constraints, safe pruning, duplicate policy and restoration.
- Greedy and Interval Algorithms
Prove when one frontier dominates alternatives; connect reachability, prefix resets, interval union, scheduling, room counts and endpoint semantics.
- Ordering, Heaps, and Selection
Match full order, rank and dynamic frontiers to insertion/merge/partition sorting, bounded heaps, quickselect, sorted streams and median invariants.
- Choosing Algorithms
Use constraints, output contracts and proof conditions to choose algorithms: a navigable decision tree, work/memory estimates, signed-window counterexamples and subset-sum regimes.
- Bits, Numbers, and Geometric Patterns
Use representation and invariants to justify XOR, carries, power-of-two alignment, modular arithmetic, matrix boundaries and exact coordinate tests.
post-training
- Supervised Fine-Tuning and Adaptation
Conversation contracts, exact loss targets, LoRA, vocabulary adaptation and reliable export.
- Preference Optimization
Learn from comparisons: DPO ratios, reference policies, beta, data quality and alternatives without confusing offline fitting with online rewards.
- Reinforcement Learning
Learn from sampled outcomes: Bellman values, policy gradients, group credit, clipped updates, verifiers, exploration, coverage and asynchronous rollout systems.
- Distillation
Transfer teacher behavior through soft targets, generated traces and feedback on student histories. Connect temperature, KL gradients, self-distillation, retention and specialist consolidation.
- Agent Training and Environments
Construct executable tasks, preserve recovery histories, train through diverse harnesses, and assign grounded outcome and process credit without losing the collection contract.
- Building and Controlling Reasoning Models
Connect reliable evaluation, inference search, verifiable rewards, teacher traces and learned effort controls into one measurable reasoning pipeline.
computing
- Distributed Services and System Design
Choose replication, caching, sharding and delivery from workload and failure contracts. Understand CAP, quorum intersection, DNS/CDN paths and a worked video-platform design.