// core engineering optimization

Tighter inner loops. Faster outer ones.

We rebuild the hottest 3% of your codebase and the workflow around it — so your service responds in microseconds, and your team ships in minutes.

The inner loop sets the ceiling.

Every system has an inner loop — the small block of code that runs millions of times per second, the build-test cycle a developer hits hundreds of times a day, the deployment train that gates every release. Optimize it, and everything above it gets faster, cheaper, and calmer.

We embed with engineering teams to profile, redesign, and ship the changes that move p99 latency, throughput, and developer velocity in the same direction. No vague audits — measured deltas, merged PRs, and runbooks your team owns when we leave.

profile · hot-path.cc
# flame graph excerpt — order book matching engine
$ perf record -F 4000 -g ./match_engine
collected 2,481,003 samples
62.1% OrderBook::insert ← std::map rebalance
14.3% malloc · jemalloc arena lock
09.7% memcpy · order serialization
04.2% syscall · gettimeofday()
# after: intrusive RB-tree + arena alloc + TSC clock
p99 1.4ms → 184µs · throughput +6.4×

// velocity telemetry

Measured against your own baseline.

Typical 12-week engagement deltas across recent inner-loop programs. Numbers are medians across our last 14 production deployments — full case studies on the Services and Industries pages.

0%

p99 latency cut

0%

CI wall-clock cut

0%

Infra cost cut

0

Merges per dev / wk

// concurrency matrix

There is no single right primitive.

Pick the wrong synchronization model and you'll spend a quarter chasing tail latency. We benchmark the candidates against your actual workload before a single line of production code changes. Hover the cells.

scale ↓ · pattern →MutexRWLockLock-freeShardedActor
1 core
100×
Baseline single-thread
100×
No contention
108×
CAS overhead
104×
Single shard
96×
Mailbox overhead
4 cores
140×
Lock convoy
220×
Reader-heavy wins
380×
Cache-line tuned
340×
Hash-partitioned
300×
Bounded queues
16 cores
165×
Contention cliff
280×
Reader fairness drops
1,180×
NUMA-aware
990×
16 shards · hot-key risk
920×
Backpressure tuned
64 cores
170×
Pathological
260×
Writer starvation
3,680×
Hazard pointers
3,100×
64 shards
2,750×
Supervisor trees

// Relative throughput (×baseline). Hover a cell to inspect. Source: internal harness · pinned threads · 99p latency budget held.

// delivery pipeline

A perf-gated path from commit to canary.

The CI architecture we ship enforces latency and throughput SLOs as a build step — regressions never reach production. Below: the typical pipeline shape after an InnerLoop engagement.

commit
git push
lint
0.4s
build
12s · cached
test
43s · parallel
perf-gate
p99 ≤ 8ms
stage
canary 5%
prod
blue/green

// PR → prod median 6m 12s · perf-gate rejects regressions > 3% on p99 before canary

Have a hot path that won't behave?

Send us a flame graph, a CI bottleneck, or a deployment story. We respond within one business day with a concrete first move.

info@innerloopresources.com