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.