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3,240 articles, newest first · page 12 of 54. For subject-based browsing use topics; for keyword lookup try search. Dates shown are assigned archive dates that order the library; they are not historical publication records.

2026
May 4, 2026 Remote Blackholing and FlowSpec Distribution How a network tells its upstream to drop traffic for a specific prefix or flow, why the trigger is a BGP route rather than a firewall rule, and what collateral damage the mechanism accepts by design. security · advanced
May 4, 2026 Variance Reduction in Stochastic Gradient Descent: SVRG and SAGA How control variates make the stochastic gradient noise vanish near the solution, why that restores a linear rate for finite sums, and what the stored state and epoch length cost. machine learning · advanced
May 3, 2026 Chroot Confines Path Resolution, Not the Process What the chroot call changes in the kernel, why a process that keeps a directory descriptor can walk out of the new root, and which guarantees the call does and does not provide. operating systems · foundational
May 3, 2026 Minimal Perfect Hashing for Static Key Sets How two-level displacement schemes map a fixed set of keys onto consecutive slots with no collisions, and why the result costs about two bits per key. algorithms · intermediate
May 3, 2026 VEX: Encoding Exploitability So a Scanner Can Stop Guessing A CVE in an SBOM is not a finding. VEX records whether a product is affected and why, with a justification token that a machine can act on and a human can audit. security · advanced
May 2, 2026 SQLite File Layout: Pages, B-Trees, and the Freelist How a SQLite database maps tables onto fixed-size pages, what the 100-byte header records, and why overflow chains and free pages make the file behave the way it does. mobile computing · foundational
May 1, 2026 Batching and the Amortization of Per-Item Cost How grouping work converts a fixed per-operation cost into a per-batch cost, where the delay comes from, and why batch size is a throughput constraint rather than a tuning knob. performance engineering · intermediate
May 1, 2026 Bitset Representation and Word-Level Rank and Select How a bitvector is stored as words, how popcount turns a prefix count into a handful of instructions, and what the two-level directories for rank and select cost in bits per element. data structures · intermediate
May 1, 2026 Durable Buffers and the Cost of At-Least-Once Export What has to be true for a queue to survive a process restart, why a write-ahead log adds a disk round trip to the export path, and what at-least-once cannot promise. observability · advanced
May 1, 2026 Internet Gateway, NAT, and Source Address Translation How a VPC reaches the public internet without exposing private addresses, why a NAT gateway is one-way, and how the translation table interacts with connection tracking and path MTU discovery. cloud infrastructure · intermediate
May 1, 2026 Reversibility as the Currency of Architectural Decisions Decisions differ less in how good they are than in what it costs to undo them. How to classify one-way doors, what preserving an option costs, and how to test a rollback path. software architecture · advanced
May 1, 2026 Ring All-Reduce and the Cost of Averaging Gradients Across Devices Why the ring algorithm moves a fixed multiple of the gradient size regardless of device count, and how bucketing hides the latency that the bandwidth term does not explain. deep learning · intermediate
April
Apr 30, 2026 Böhm Trees, Separability, and What Normal Forms Cannot Distinguish Why beta-eta equivalence fails to identify terms that agree on every argument, how Böhm trees record the observable behaviour of a term, and where the separability theorem stops. computation theory · advanced
Apr 30, 2026 Logical Plans and Rewrite Rules That Preserve Results Why the planner rewrites a bound query into relational algebra before choosing algorithms, and which transformations are safe under NULLs, outer joins, and volatile functions. databases · foundational
Apr 30, 2026 Median-of-Medians and the Deterministic Linear Selection Bound Why grouping into fives makes the pivot provably good, how the recurrence resolves to a linear bound, and why the constant keeps it out of hot paths. algorithms · advanced
Apr 30, 2026 Verifying What a Screen Reader Actually Says How speech output is produced from accessibility events, why announcement assertions are brittle across reader versions, and which properties can be tested stably. accessibility · intermediate
Apr 29, 2026 Name Resolution and Binding a Query to the Catalog How an unresolved syntax tree becomes a typed expression tree: namespace scoping, column ambiguity, view expansion, and where implicit casts are inserted. databases · foundational
Apr 29, 2026 Process Start Records as the Unit of Execution Evidence Why the parent-child relationship and process start time are the two facts an investigation needs first, what records the kernel actually keeps, and where those records disappear. security · foundational
Apr 29, 2026 Rise Time, Electrical Length, and When a Trace Stops Being a Wire The criterion that separates a lumped connection from a transmission line, how dielectric constant sets propagation delay, and why slow edges on long traces still misbehave. hardware engineering · foundational
Apr 29, 2026 Single-Stepping: One Flags Bit and Its Cost per Instruction The trap flag makes the processor raise an exception after every instruction. How debuggers use it, why stepping over a call needs a breakpoint instead, and where it does not exist. developer tools · intermediate
Apr 29, 2026 Why Queueing Delay Rises Sharply Near Link Utilization How the shape of the M/M/1 waiting-time curve explains the knee in latency-versus-load graphs, and why utilisation targets are set where they are. networking · foundational
Apr 28, 2026 Depth, Width, and the Linear Regions of ReLU Networks Every rectified network is a partition of its input space into cells where it computes an affine map, and the count of those cells grows polynomially in width and exponentially in depth. deep learning · advanced
Apr 28, 2026 Differential and Linear Cryptanalysis as Trail Counting The two classical attacks reduce to finding high-probability differentials and high-bias linear approximations, and both are bounded by the same active S-box count. cryptography · advanced
Apr 28, 2026 Store Buffers and the Total Store Order That Replaces Sequential Consistency How a per-core store buffer hides cache-miss latency, exactly which four orderings TSO keeps, and why load-load reordering is forbidden while load-store is not. computer architecture · foundational
Apr 27, 2026 Commit Rules, Figure 8, and Why a Leader Cannot Trust Its Log Why Raft only commits entries at a term boundary, the reordered-commit scenario that defeats the naive rule, and how the commit index interacts with log repair. distributed systems · intermediate
Apr 27, 2026 Granularity and the Sequential Cut-Off How to size parallel tasks so that scheduling overhead stays below the work they contain, and how the optimum shifts with span, memory behaviour, and the runtime. algorithms · intermediate
Apr 27, 2026 How a NAND Cell Stores a Bit: Threshold Voltage and Read Levels The floating-gate transistor, the programmed charge that shifts its threshold, and why adding levels to a cell shrinks the margin every read decision depends on. hardware engineering · foundational
Apr 27, 2026 LALR Table Construction and What the Conflicts Mean How LR(1) item sets become LALR states, what shift-reduce and reduce-reduce conflicts actually report about a grammar, and when a precedence declaration is the correct repair. compilers · intermediate
Apr 27, 2026 Score Calibration for Blended Ranking Why a ranker optimized for ordering produces scores with no absolute meaning, how to fit a monotone calibration, and what breaks when the query mix shifts. information retrieval · advanced
Apr 27, 2026 Semantic Tokens: Relative Encoding and Delta Updates How a language server describes highlighting as a flat array of integers, why each token is encoded relative to its predecessor, and how delta edits over that array are applied without corrupting it. developer tools · advanced
Apr 26, 2026 Content-Addressed Provenance Graphs for Derived Outputs Recording each step as a node keyed by the hash of its inputs, code, parameters, and environment, so that any output can be traced back to the exact bytes and commands that produced it. scientific computing · intermediate
Apr 26, 2026 Stack Unwinding With and Without Frame Pointers How a profiler recovers a call chain from registers and memory, why omitting frame pointers breaks the cheap method, and what DWARF call-frame information costs instead. performance engineering · intermediate
Apr 25, 2026 Control Hazards: What a Branch Costs Before It Resolves The cycles a taken branch throws away in a five-stage pipeline, why the penalty equals the number of fetches in flight, and how prediction turns a fixed loss into a probabilistic one. computer architecture · intermediate
Apr 25, 2026 Fold as the Universal List Eliminator Why foldr is the unique homomorphism from lists to any algebra, how the universal property turns programs into equations, and where foldl diverges from it. programming languages · foundational
Apr 25, 2026 Writing and Reading a Magnetic Bit on a Spinning Platter How a write head sets the direction of magnetisation in a granular medium, why transitions rather than levels carry the data, and what the read sensor and channel must recover. hardware engineering · foundational
Apr 24, 2026 Cookie Scoping, SameSite, and the Site Boundary How cookies are addressed by host and path rather than of origin, what SameSite Lax and Strict actually permit, and where domain-scoped cookies leak across unrelated applications. web platform · foundational
Apr 24, 2026 Means, Percentiles, and What a Tail Measurement Can Answer Why the mean and the p99 are answers to different questions, what a percentile of a pooled sample says about an individual request, and the sub-second window where percentile estimates become unstable. performance engineering · intermediate
Apr 24, 2026 Priority Inversion and the Protocols That Bound It How a low-priority lock holder can block a high-priority thread indefinitely, what inheritance and ceiling protocols each guarantee, and why both need the scheduler inside the lock. operating systems · advanced
Apr 24, 2026 Restoring Focus After the Focused Element Disappears When a focused node is removed the browser falls back to the body, and the next Tab press restarts at the top of the page. How to choose a restoration target from structure rather than from memory. accessibility · intermediate
Apr 24, 2026 Shadow Traffic and Differential Comparison Before a Cutover How mirrored requests expose behavioural differences between two implementations, why response bodies rarely compare cleanly, and what a comparison harness must normalise. cloud infrastructure · intermediate
Apr 24, 2026 Short Counts: Why read and write Return Less Than Asked A successful read or write may transfer fewer bytes than requested, and the reasons differ by object type. The cases differ by object type, and each needs a loop that distinguishes end-of-file, interruption, and a partial transfer. systems programming · foundational
Apr 24, 2026 Tiered Compilation and Deoptimization: Undoing a Speculation How a runtime decides when to compile, what a speculation record contains, and how execution resumes in the interpreter when a guard fails. programming languages · advanced
Apr 23, 2026 Attributing Jank to a Specific Pipeline Stage A method for turning a frame timeline into one responsible stage, why the naive comparison of durations misleads, and how to distinguish queue latency from work latency. mobile computing · advanced
Apr 23, 2026 Bilinear Weighting and the Tent Reconstruction Filter How four texel taps and two linear interpolants reconstruct a continuous signal, why the resulting kernel is a tent, and what that kernel does to frequencies above half the texel rate. computer graphics · foundational
Apr 23, 2026 Hedged Requests, Tied Requests, and the Cost of Buying Back the Tail When issuing a second copy of a request reduces latency enough to justify the extra work, how to pick the hedge delay from the latency distribution, and why request tying costs a round trip. performance engineering · advanced
Apr 23, 2026 Runtime Reflection: Metadata Layout and Dispatch Cost What a class descriptor actually contains, why reflective invocation cannot be inlined, and how annotation lookup and dynamic proxies turn a static call into a table walk. programming languages · intermediate
Apr 23, 2026 What a Private Field Actually Hides How access control is checked, why private members remain reachable through reflection or linking tricks, and why the module rather than the class is the enforceable boundary. programming languages · foundational
Apr 23, 2026 What a Shuffle Moves Between Map and Reduce Stages The mechanics of the map-side write, the network fetch, and the reduce-side merge: what actually crosses the wire, and why the stage boundary exists at all. data engineering · foundational
Apr 22, 2026 Alpha-Equivalence and de Bruijn Indices in the Lambda Calculus Why the names of bound variables carry no information, how alpha-equivalence is defined, and how nameless indices turn it into structural equality with a shift operation. computation theory · foundational
Apr 22, 2026 Chunked Prefill and the Interference It Removes Prefill is compute-bound and decode is bandwidth-bound, so running them in the same iteration makes each wait on the other. Splitting prompts into chunks is the standard remedy. inference systems · foundational
Apr 22, 2026 Cuckoo Filters: Fingerprint Placement and the Load-Factor Ceiling How two-bucket cuckoo hashing with stored fingerprints supports deletion in less space than a counting Bloom filter, and why displacement fails near full occupancy. data structures · foundational
Apr 22, 2026 Inter-Annotator Agreement as a Ceiling on Measured Quality If two careful human raters disagree on a third of items, no scorer can exceed that agreement. Cohen kappa, Krippendorff alpha, and why the ceiling is not a target. inference systems · intermediate
Apr 22, 2026 Mapping RTP Clocks to Wall Time for Cross-Stream Synchronization Sender reports tie an RTP timestamp to an NTP instant; using that correspondence to align audio and video exposes clock offset, drift, and the limits of the mapping. internet protocols · advanced
Apr 22, 2026 MTU and Fragmentation Across a VPC Boundary Why the usable MTU inside a virtual network is smaller than the physical link MTU, how encapsulation and translation each consume bytes, and what happens when a packet that needs fragmenting is dropped instead. cloud infrastructure · intermediate
Apr 21, 2026 Banding, Bit Depth, and the Trade-offs of Error Diffusion Dither Why quantization on an 8-bit gradient shows contours, how the eye's contrast sensitivity makes them visible, and what ordered and error-diffusion dither cost. computer graphics · intermediate
Apr 21, 2026 Heap Growth and Release: brk, mmap, and Trim How a process obtains heap memory from the kernel, why a large allocation bypasses the main heap entirely, and what returning pages actually costs at the page-table level. memory systems · advanced
Apr 21, 2026 Live Regions and Asynchronous Announcements How aria-live regions cause screen readers to announce content that changes without focus moving, and how the polite and assertive politeness levels are implemented. accessibility · intermediate
Apr 21, 2026 The Overhead Budget of a Sampling Profiler Where the cost of continuous profiling actually goes, why per-sample cost and sample rate multiply, and how aggregation location changes the bill. observability · intermediate
Apr 20, 2026 Designing a Key Service Interface That Cannot Be Misused Why a key store should expose operations rather than keys, which parameters belong in a request, and how context binding and audit change the trust model. cryptography · advanced
Apr 20, 2026 State as a Mapping Between Addresses and Real Objects What a provisioning state file actually stores, why it is the tool's only durable record of identity, and how concurrent access corrupts that record. cloud infrastructure · foundational

2026

April